| Author | Message | ||
| andrea lazzaro (380bhp)
New member Username: 380bhp Post Number: 1 Registered: 6-2003 |
I hope someone can help me with this one. During a holiday in Italy two weeks ago my '96 F355 one morning showed only 2.5 bar max oil pressure when hot, regardless of engine speed, and the engine was not running smoothly. Until the previous day, oil pressure had always been healthy at 5-6 bar with strong performance. The Ferrari mechanic that examined the car stated that: 1) the pressure gauge is OK 2) Oil pressure is ok when cold (5 bar) but it falls to 2.5 bar (max) when hot. Idle pressure is almost zero, but not low enough to trigger the warning light. 2) there is virtually no compression in cylinder 5. The mechanic says it could be a jammed hydraulic tappet (causing a valve to stick open and causing the oil pressure reduction). Otherwise he also says it could be something more serious - a distorted liner? Could this problem have anything to do with the valve guide problem? Any help and suggestions will be very, very welcome. | ||
| Dave L (Davel)
Member Username: Davel Post Number: 277 Registered: 7-2001 |
Roger that Dave Helms  | ||
| Dave Helms (Davehelms)
New member Username: Davehelms Post Number: 46 Registered: 5-2003 |
Dave L, I did not take any offence to your post at all. You advice was direct, accurate, and to the point. My responce was regarding the "95" issue. We are talking about a 97 with the same valve guides/problems, that most folks think is isolated to the 95 model year. It isnt, and carries on through 97. | ||
| Mitch Alsup (Mitch_alsup)
Member Username: Mitch_alsup Post Number: 727 Registered: 4-2002 |
"I bet that if the average Ferrari owner drove their cars 15k miles a year" I bet that if most owners drove their cars 15K miles a year that most cars would need less servicing than the do right now! | ||
| Frank Parker (Parkerfe)
Intermediate Member Username: Parkerfe Post Number: 2341 Registered: 9-2001 |
It appears that Ferrari pays attention to it's customers and knows that most drive their cars very few miles a year so parts don't need to last that long. I bet that if the average Ferrari owner drove their cars 15k miles a year that Ferrari would soon design its cars and parts to last longer....or go bankrupt. | ||
| Dave L (Davel)
Member Username: Davel Post Number: 275 Registered: 7-2001 |
Didnt mean to upset anyone here. Just answered the guys basic question on what to look for...sorry. Didnt mean to indict the entire line of production. | ||
| Dave Helms (Davehelms)
New member Username: Davehelms Post Number: 44 Registered: 5-2003 |
Many good points, but I think that the main point is being missed here. Ferrari may fall short on many of the bells and whistles, but engines they know! This is what the whole marque, and legend, is built around. But, on this one they screwed up. Dave L, this is what the discussion is all about, it is not a "95 problem" at all, it goes beyound that! | ||
| David Prall (Davidpra)
Junior Member Username: Davidpra Post Number: 161 Registered: 2-2001 |
Oh yeah, by the way, if you are stuck with Titanium valves (make sure that they are in fact, Titanium), I would definitely go with Steel guides ---- even in an Aluminum head --- all things considered. Good luck... | ||
| David Prall (Davidpra)
Junior Member Username: Davidpra Post Number: 159 Registered: 2-2001 |
PS Tim ---- I don't want to buy your car after all!!! (just teasing) | ||
| David Prall (Davidpra)
Junior Member Username: Davidpra Post Number: 158 Registered: 2-2001 |
One more theory: Assuming there is sufficient lubrication and no excessive friction, the main factor that leads to wear (metal on metal) is �clearance�. If the fit between the valve stem and the guide is sloppy, contact stresses will be greatly elevated, and excessive wear will precipitate. In such a scenario, it doesn't matter what materials the parts are made from --- they will wear. That understood, here is the problem with a Titanium valve (stem) and a Bronze guide on a 355 engine: Aluminum [14] (the cylinder head material) and Bronze [9] have fairly high [CTE's] (coefficient of thermal expansion) while Titanium [5] and Steel [6.5] have fairly low [CTE�s]. In an application where heat is high and tight clearance is required, i.e., the cylinder head in a 355 engine, you want the CTE�s of the materials for the valve and the guide to be closely matched. So, these combinations are better: Valve (Ti) � Guide (Steel) Valve (Steel) � Guide (Steel) And, these combinations are worse: Valve (Ti) � Guide (Bronze) Valve (Steel) � Guide (Bronze) Referring to the CTE�s above, you can see that when a Titanium valve is run in a Bronze guide, the mismatch is at its worst [9 to 5]. With that configuration, excessive clearance will result at elevated operating temps, and high wear is likely to occur. Also, looking at the CTE values given, you can see that a configuration using a Steel valve in a Bronze guide [9 to 6.5] is a better choice than the Titanium / Bronze combination above. I don�t know exactly what combinations Ferrari has used in the 355, but if the previous posts are accurate in that a Titanium valve and a Bronze guide configuration was used, I would say that is not an optimum design from the standpoint of wear. Steel and Steel is optimum for wear but has some other drawbacks (high mass, high friction). In general Steel guides are bad because they don�t match the CTE of the Aluminum head and Steel to Aluminum has a high Galvanic potential which promotes corrosion. Steel guides are better in Cast Iron heads. Bronze guides are better for wear as far as lower friction is concerned, and they will work better in an Aluminum head, both CTE wise and corrosion wise. The conclusion is likely that given an Aluminum head, Steel valves with Bronze guides seems a good choice --- However, there are certainly other factors to consider in a complete design, and we haven�t touched on those. In the end, the optimum combination could be something else then. I don�t design Ferrari engines for a living, so I don�t have the definitive answer to the problem. But, apparently (and regrettably for all the 355 owners out there) neither does Ferrari --- LOL!!! | ||
| Tim Barnett (Tim_barnett)
New member Username: Tim_barnett Post Number: 42 Registered: 4-2003 |
Let�s review what we know (and get this thread back on track): 1. The 1995 355�s were known to have suffered problems with their valve guides. I�m not suggesting that every 1995 355 is prone to this problem. There will always be exceptions to this rule, however such evidence is often anecdotal. Art, et al., I will keep my fingers crossed for you. But there are more than enough examples of premature valve guide wear to support a trend. For supporting evidence, see past threads on Fchat, the 355�s Buyer�s Guide in Forza (BTW that�s my silver Berlinetta in this issue), speak to Dave Helms or any Ferrari dealer that services a large number of 355�s, etc. 2. Ferrari itself recognized this trend and chose to replace guides in many cases for owners even outside the warranty period. I understand that facts and circumstances are probably different in every one of these cases. I�m sure it helps if you�ve purchased numerous new Ferrari�s in the past, however Ferrari, it seems, is rarely willing to make such exceptions unless they are to correct known problems or defects. Case in point: Mr. Doody�s negative experience with his 550. Several known problems appeared with his car outside of the warranty period. FNA arguably did the right thing and supported him. 3. Ferrari further recognized this trend when it deliberately changed the guide material to sintered steel with the 1996 model year. Granted, it�s obvious to me that Ferrari was also careful not to let any of the old bronze guides go to waste otherwise I wouldn�t be in this mess� 4. No one has come forward on this board nor can I find even one example of an early valve guide failure on 355�s with the steel guides. Ferrari of Denver has never seen one. Ferrari of Houston has never seen one either. Not one. BTW, F of Houston is one of the largest and most respected F dealers in the country. And with more experience with the Challenge Series cars than just about anyone, if there was a problem with the steel guides, F of Houston would have seen it. All theories aside, what does the evidence above suggest? There is a problem with the BRONZE valve guides. There may be other interesting theories to further explain the problem, but I just don�t see any basis for them. Am I angry to have to spend a lot of money at 21,500 miles on a major repair? Absolutely. Is my anger compounded by the fact it�s due to a known problem? Without doubt. How do I feel having paid extra for a car where supposedly the problem had been fixed? I don�t even need to answer this one� So the question for me remains: Should my 1997 355 have come with bronze guides in the first place? I remain convinced it should not. But before I go cap in hand to FNA, I would like to know I stand on firm ground. | ||
| Dave L (Davel)
Member Username: Davel Post Number: 274 Registered: 7-2001 |
Well for a 355 start with the basics, PPI, records and a chat with the mechanic/shop who maintain it. Next check the headers, catalytic converter. They are known to be weak areas, other than that except for the dreaded 95 valve guide problem, they are pretty straight forward cars. | ||
| J R K (Kenyon)
Member Username: Kenyon Post Number: 323 Registered: 10-2002 |
Is it not best to go for the lastest year of what ever Ferrari model you buy. I wanted a F355 1994 / 1995 But I was advised to buy the last of of the 348 models. I bought a late 1994 348 Spyder. I researched for nearly a year before purchasing a Ferrari. This is my first Ferrari. Well second I destroyed a 348 GTS 1994 only had it a hour. Long story. For one last time, Please can someome tell what to look for on F355. i.e faults and major upgrdaes etc. | ||
| JRV (Jrvall)
Intermediate Member Username: Jrvall Post Number: 1658 Registered: 11-2002 |
>>>There is so much heat developed in the cylinder heads from so much going on with the five valves. This in conjunction with the head only having coolant in the lowest inch and quarter of the casting makes the heads almost entirly cooled by oil. They were saying that driving the car hard then shutting it down could cause the oil to cristilize in the head plugging the oil feed passages.<<< Now we're getting somewhere! I find the above explanation far more belivable and more directly a possible root cause of the problems than "soft guides" . >>These experts that I sought admonished me to only consider a 1998-99 model, which apparently, had improved metallurgy and seals.<< Tim, how much data "really" exists on 98-99 models with say 25K-30K miles, (which shouldn't really be a lot of miles on an engine) from which to give enough data for a comparative analysis? | ||
| James Selevan (Jselevan)
Member Username: Jselevan Post Number: 572 Registered: 6-2002 |
Tim B. - when looking to purchase a 355 over the past several years, everyone I contacted offered that the "early" models, that is, prior to mid-1998, were prone to valve-stem/valve guide failure. These experts that I sought admonished me to only consider a 1998-99 model, which apparently, had improved metallurgy and seals. Not being an expert on this model, I cannot offer specifics concerning the reason for failure or the solution. Jim S. | ||
| Craig Nelson (Monza456)
New member Username: Monza456 Post Number: 13 Registered: 2-2003 |
When I went to ferrari 355 school in 95 we were told people should always let there 355's idle about five minutes before shutting them down especialy after driving hard. There is so much heat developed in the cylinder heads from so much going on with the five valves. This in conjunction with the head only having coolant in the lowest inch and quarter of the casting makes the heads almost entirly cooled by oil. They were saying that driving the car hard then shutting it down could cause the oil to cristilize in the head plugging the oil feed passages. So lets say these cars arent having this problem so severe but are having enough of a problem that a little build up from the oil burning on the valves is causing them not to let enough oil to the guides for proper lubrication. How many times have we all given people a fast run for there first ever ride in a Ferrari just to take them back and shut it down? I can even remember taking cars out on the pre delevery inspection and running them hard and putting them away fast. Just food for thought guys... | ||
| Tim Barnett (Tim_barnett)
New member Username: Tim_barnett Post Number: 40 Registered: 4-2003 |
Jim S., What "improved-updated" valve guides are you referring to? Are you saying that it's reasonable to expect bronze guides in a '97? Tony's post suggests perhaps yes depending on the engine assembly #, however my engine assembly # is outside the range he quoted. | ||
| Tim Barnett (Tim_barnett)
New member Username: Tim_barnett Post Number: 39 Registered: 4-2003 |
JRV, Good question. Although do you think it's fair to say that we're seeing at least greater longevity with the steel guides? Furthermore, given that the 355 was one of the most popular models of all time and given that it was campaigned for years in the Challenge Series, I would have thought there would now be enough data to draw some conclusions. | ||
| James Selevan (Jselevan)
Member Username: Jselevan Post Number: 569 Registered: 6-2002 |
I assumed it was common knowledge that mid-1998 and later had "improved-updated" valve guides. Those cars manufactured before mid-1998 were subject to valve guide/valve failure. That there seems to be surprise over failure of 1997 and earlier is, well, a surprise to me. Jim S. | ||
| JRV (Jrvall)
Intermediate Member Username: Jrvall Post Number: 1652 Registered: 11-2002 |
Tim, don't you think it's a might premature to call this issue a 'done deal'?? I hardly think enough data has been compiled or we've had enough time to gather a large enough sampling of data to call it "fix is in" imo. | ||
| Tim Barnett (Tim_barnett)
New member Username: Tim_barnett Post Number: 38 Registered: 4-2003 |
Ben, You make some interesting points. However I would find it easier to agree with you if we were seeing a rash of premature failures with the steel guides. So far they appear to be reliable. | ||
| Tim Barnett (Tim_barnett)
New member Username: Tim_barnett Post Number: 37 Registered: 4-2003 |
Tom, Regarding the valve job you did on the 1997 355, were they steel or bronze guides that wore out? | ||
| Raymond A. Castelhano (Oglmlw)
New member Username: Oglmlw Post Number: 20 Registered: 5-2003 |
Well put Dave! In a way it is too bad that there are so few 250s. And therefore so few folks will ever drive them but being unique is part of what makes Ferrari Ferrari. MrC | ||
| Dave Helms (Davehelms)
New member Username: Davehelms Post Number: 39 Registered: 5-2003 |
Raymond, I would have a very hard time debating your point on the 250's. When I took a job at World Ferrari many years ago, the first car I worked on there was a TdF, and after driving it I thought no better car had ever been built! Then I did a gaggle of 3 SWB's and they climbed to the top of the list. But one day the GTO rolled in the shop .... I will fully agree with you, the 250's have a place in my heart that will never be taken over! I think the 355 represents the first Ferrari that is truely a daily driver, with the performance and agility of a race car. As I write this, I think back to when we were Vintage racing all the 250's, and failures were almost nill. We would beat the tar out of those cars, change the oil, adjust the valves, and do it again year after year. David C brings up a very good point. There are many trade offs for performance sake pertaining to valve guides, their length, and material. The old 128C, TdF engines used the navel bronze guides (read "soft") and would hold up with big cams (GTO profile) just fine at any RPM. They too would smoke like hell when first started, but that was expected by the designers and builders. It was the end users (owners)that determined this was unexceptable and started putting external drain backs and seals on those guides, and the reliabilty and life went down from there. I dont have any problem with the steel guides, as long as they are compatible with the amount of oiling, temp, RPM ect.., and it is a well engnred fix that was well tested prior to its introduction. | ||
| Jeff B. (Azferrari)
New member Username: Azferrari Post Number: 5 Registered: 4-2003 |
I bought my '95 F355 a couple of years ago. I had asked a Ferrari mechanic before purchasing about the valve guide issue, as well as the cracked exhaust manifold issue, and the "lurching initial throttle at low rpm" issue. I was told that the valve guide thing was a little "overblown" and my car "would be showing problems by now" (it had 8500 miles when I purchased it. It now has 11,000 miles.) So far, no valve guide or exhaust manifold problems (knock on wood). The initial throttle tip in does bug the hell out of me though. Many articles that I have read on the F355 have mentioned this fault. I have replaced the circular throttle "thingy" on top of the engine with the updated one, along with new bearings. It helps a little. Only difference between the two parts is the amount the throttle cable wraps around it. I have no "sticking" problem. Everything moves very freely. I am convinced that this is a vacuum problem. Anyway, I feel for you owners that paid more to hopefully bypass the valve guide problem. Hopefully, Ferrari will do something about it. | ||
| P. Thomas (Ferrari_fanatic)
Member Username: Ferrari_fanatic Post Number: 320 Registered: 4-2003 |
FYI, for those of you that don't know. Tony has contibuted multiple technical articles published in Forza Magazine. His F-car background, knowledge and passion is unparalleled. | ||
| Ali Haas (Aehaas)
New member Username: Aehaas Post Number: 14 Registered: 5-2003 |
Ask what oil the owners were using. Some oils are corrosive to yellow metals. Also lubrication may be minimal if the oil they used was too thick if they drove the car at around town temperatures. Too thick an oil will cause just as much damage as too thin if the engine is not operated at that oils designed operating temperature. aehaas | ||
| Raymond A. Castelhano (Oglmlw)
New member Username: Oglmlw Post Number: 18 Registered: 5-2003 |
There is no telling what auto companies will or will not help you with these days. FNA may not look at this as a potential cost of fixing your car but as a potential to fix all 355s with bronze guides. Big numbers there! They did ackowledge the problem (see Mr. Palladino's post). But they have not agreed to retrofit the newer guides. Generally. the start of factory production changes are not tied to an exact car (serial number) but to a range so the factoria could simply say that this car was built before the change hit the production line. My experience with various manufacturers tells me that FNA will ask (read tell) you to take the car to your local dealer. If I were in your place I would go down to Ferrari of Denver or Ferrari of? and discuss the problem with them. If they will agree to take the issue up with FNA and really get behind you, you have a good chance. Good luck Tim. MrC BTW Mr. Helms, I really like 355s also but I will take any 250 (1950s -1960s) over any 355 as the best Ferrari yet. Oops, that could get things going. "The best yet" might produce 4999 posts before we decide that 250s were best. | ||
| Tim Barnett (Tim_barnett)
New member Username: Tim_barnett Post Number: 32 Registered: 4-2003 |
Thank you everyone for your input so far. My follow up question is this: Should FNA stand by me on this problem? When I bought my 355, I knew I wasn't buying a car that's renowned for reliability. I've already had to address several problems already without complaint. However I also honestly expected my 355 to come with the more reliable steel guides. Please someone tell me that FNA might have a heart on this issue! Also, please give me advice on what approach is most likely to reach friendly ears at FNA. No matter what happens, I'll continue to post my experience on this board. | ||
| Ben Millermon (Brainsboy)
Member Username: Brainsboy Post Number: 331 Registered: 5-2001 |
Keep in mind what JRV said, Its not always the valve guide thats bad. There is a reason why it is wearing., I think this soft bronze guide is hogwash. IMO going from bronze to steel is not a cure, its just a way to try and cover an existing problem. The problem lies elsewere, probably in the teflon seals, or a combination of things. | ||
| Tim Barnett (Tim_barnett)
New member Username: Tim_barnett Post Number: 31 Registered: 4-2003 |
Tony, My engine number is 45459 (?) | ||
| Robert McNair (Rrm)
Member Username: Rrm Post Number: 406 Registered: 5-2002 |
Tony, I second everything Philip said. I hope you choose to contribute to this board. I'm sure you will be warmly welcomed. | ||
| FABS (Caruso360)
New member Username: Caruso360 Post Number: 29 Registered: 5-2003 |
Hey Ferrari are you paying attention? | ||
| Tom Bakowsky (Tbakowsky)
Member Username: Tbakowsky Post Number: 407 Registered: 9-2002 |
I did a valve job on a late 97 355. The guides were completly toast. So far gone infact that it resulted in a burned exhaust valve. It also resulted in the nikasil coating on the cylinder liner to be "washed" off, and ruined the piston rings. I think Ferrari is full of crap when they say they fixed the problem. Sure they found the problem but only started using the new guides after they ran out of the old ones. It's the person who buys the car I feel sorry for because they are the one paying for the upgrade not Ferrari. | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 255 Registered: 7-2002 |
Tony Your reputation preceeds you. I am sure I speak for many, great to see you as part of this Board. Your technical (and other) inputs are welcome. Philip | ||
| Tony Palladino (Ferrarimechanic)
New member Username: Ferrarimechanic Post Number: 4 Registered: 2-2003 |
Subject F355 Valve Guides: Starting from assembly #27689 all 355 Engines are equipped from the factory with new Valve guides, which are manufactured with Sintered Steel instead of Bronze. New updated part numbers are: Intake Guide #176437 Exhaust Guide #176438 Note: will need new style Guide Installer. The assembly number is located in the engine compartment/Plate and I have seen some very early 98's with lower numbers. Also out of many sub-27689 355's I service only one has had a leakdown problem and it was a Street/track car and had went through two sets of Exhaust Manifolds under warranty and the last time the owner ran the car for sometime with a blown exhaust manifold knowing he was going to do a Valve Job {FNA BO on Manifolds at the time}. Also note that most the cars I service were purchased new or low miles and ran Swepco 306 Engine oil and Swepco 503 Fuel Additive. Cheers TP RE: TSB 764 PS Do I love early 355's "Yes" Early 355's rock! | ||
| JRV (Jrvall)
Intermediate Member Username: Jrvall Post Number: 1619 Registered: 11-2002 |
From the other thread: **Have my 97 355 in at Blackhorse in Los Angeles, and they state cylinder 5 is down 30% and 6 is down 20% on the leakdown, and that they ran it twice to make sure. Car is super low miles at about 5k. ** granted no one knows what these other issues are all about (or even if issues exist based on the inconclusive results & questionable testing techniques) but what if the issues are real and turn out to be guide related? | ||
| Tim Barnett (Tim_barnett)
New member Username: Tim_barnett Post Number: 30 Registered: 4-2003 |
I suppose one way to look at the problem is to ask the question: Has anyone experienced premature wear with the later type valve guides? | ||
| Ben Millermon (Brainsboy)
Member Username: Brainsboy Post Number: 330 Registered: 5-2001 |
I agree with JRV on the guilds. I have noticed that on some of the 308's it seems as if the teflon seals seal too well. This in turn doesnt leave enough oil to lube the valve guilds and causes premature wear. Im not sure what type of seal the 355 has on it, but it may be wise to investiage that end of it | ||
| JRV (Jrvall)
Intermediate Member Username: Jrvall Post Number: 1617 Registered: 11-2002 |
Mitch....very good questions and points. and more along the lines I think the real answer to the problem lies. Guides wear out because something (the valve stem) is rubbing against them to hard or without adequate lubrication or both, along with the possibility of to much heat, not simply because they are too soft ime. | ||
| Ken (Allyn)
Member Username: Allyn Post Number: 926 Registered: 10-2001 |
My 72 TC Europa has 'short bronze' valve guides and they lasted 35k miles for the little old man who purchased my car new. I'm at 53k miles now and I rev it pretty high a lot so I'm holding my breath for the next valve adjustment to see what shape the guides are in. I will look in to steel to see if that's an option for me. | ||
| Mitch Alsup (Mitch_alsup)
Member Username: Mitch_alsup Post Number: 695 Registered: 4-2002 |
Just an idea: The old valves were steel, while the new valves are titanium. Does titanium (as used in valves) have some abrasive property that steel does not? Do the honing marks on the titanium valves wear the valve guides in a way the honing marks on steel valves would not? | ||
| arthur chambers (Art355)
Intermediate Member Username: Art355 Post Number: 1835 Registered: 6-2001 |
Bad guides can cause a loss of compression, but if the guide is that bad, they it is a major failure. Art | ||
| Dave Helms (Davehelms)
New member Username: Davehelms Post Number: 33 Registered: 5-2003 |
It is a given the 95's had problems, and to the point that Ferrari made a major production change to correct it in 96. The issue here is the car is a 97, virgin paint markings on sub frame bolts (ie.. engine never out, or someone went to a great amount of trouble to line up the old paint marks), and has the bronze guides! I read the debate here about how guides can not cause low compression. This is simply not the case, of course they can cause the problem. Consider the speeds the valve opens and closes. Unless the valve is held accurately in the guide it has little chance of ever seating squarely when it closes. In this case when the valve is held in the open position and rocked back and forth, there is near 3/16 inch of movement at the head of the valve. Consider that amount of movement, and look at the stem diameter of 6mm, and that guide is not loose, its all but missing! Take that amount of wear, and multiply it by 40, and what do you suspect the chances are that you will get them all to seat squarely and have good compression in all cylinders? Bronze used to be the end all material for guides, but consider the word bronze now covers an untold number of variations. The old Ferrari engines used a naval bronze material for the guides, and we used to make replacements out of silicon/ aluminum bronze because of the better wear it offered, and the expansion rate stayed near to the same as the early material. This was ness. so the guide stays tight in the head. The decission factors used for guide material of the early 12 cyl engines is far differant than it is now. Remember, same RPM, near the same displacement, but the the valve mass has changed. What once was a huge single valve, is now 3 small light weight valves that SHOULD NOT wear things out as fast! The real problem at hand here, is the known problem of bad guide wear (bronze) in the 95's now appears it is not isolated to the 95's after all. This is a concern when folks are stepping up to pay bigger $ for a post 95 car to avoid a known problem. After all this, I still think that the 355 is hands down the best all around car Ferrari has produced to date. | ||
| Hans E. Hansen (4re_gt4)
Intermediate Member Username: 4re_gt4 Post Number: 1384 Registered: 4-2002 |
Neal: With forced induction, all bets are off. F1 motors were doing over 1000hp out of 1.5L. Anything is possible with a turbo. But over 100hp/liter is damn near impossible, naturally aspirated, with a street engine. Honda S2000 being a notable exception. | ||
| JRV (Jrvall)
Intermediate Member Username: Jrvall Post Number: 1614 Registered: 11-2002 |
>>>I wonder if it's something to do with the valve angles and cam lobes on these engines?<< Lol..you reading my mind? Yes I think we'll find something along the lines of valve angle, swipe angle, inadequate lubrication going on and the real fix will be correcting some or all of the above.... Ferrari has a long history of valve train experiments that failed...or were weak under actual use. Including recently all the first 333SP engines that were blowing with valve train failures. Anyway, time will tell, and until more data rolls in I'm not a buyer of "soft guides". | ||
| David Moore (Speedmoore)
Junior Member Username: Speedmoore Post Number: 51 Registered: 4-2003 |
JRV said...... "I'm not completely convinced these anomolies are simply "soft guide" problems either. Old motors have crappy guides and huge heavy valves in comparison and they don't crap out so quickly..." Very True I wonder if it's something to do with the valve angles and cam lobes on these engines? Always intrigues me everytime I look at this particular valve train. | ||
| JRV (Jrvall)
Intermediate Member Username: Jrvall Post Number: 1612 Registered: 11-2002 |
>>Second opinion time? << well sort of, but I can't put a wholesale yes on your description...the reason being, a well worn guide can/does allow the valve to wobble and operate at irregular angles to the seat.....when this happens the valve can hit the seat improperly and create sealing irregularities...I'm not saying this happened in this case...but it can/does happen. There is actually alot going on in a valve train, rotation, carbon build up, cleaning, sealing, and when all of these events aren't happening perfectly, anomolies can and do occur. I'm not completely convinced these anomolies are simply "soft guide" problems either. Old motors have crappy guides and huge heavy valves in comparison and they don't crap out so quickly... | ||
| David Moore (Speedmoore)
New member Username: Speedmoore Post Number: 47 Registered: 4-2003 |
Hmmm, seems maybe they should have used Manganese Bronze or Beryllium Copper. | ||
| Andrew A. Illes (Andyilles)
Junior Member Username: Andyilles Post Number: 61 Registered: 10-2002 |
A low compression test in one cylinder in a relatively new engine means only one of two things.... either a broken ring, or one of the valves isn't seating, or is burned. A bad guide, except in an EXTREME case will not, and cannot, produce a low compression reading.. it's valve will still seat... plus, the guide is outside the combustion chamber, and thus, has nothing to do with compression. Second opinion time? | ||
| FABS (Caruso360)
New member Username: Caruso360 Post Number: 24 Registered: 5-2003 |
This is the way it should be for rallying around another's situation of major expense. Surely, this would be a non-issue if we had the pocketbook of "Gates" like persons. Most, if not all of us are hardworking, save and pay for kind of people who spend the time in doing the research to make a qualified decision.We have the unnerving passion of wanting and having a Ferrari. FNA seems to care less despite the fact that a modern day F car costa at least a $100k. Keep it up! | ||
| arthur chambers (Art355)
Intermediate Member Username: Art355 Post Number: 1824 Registered: 6-2001 |
Neal: Make sure that its a defect, not abuse. My 355 hs 34k and doesn't have that problem. Art | ||
| neal (95spiderneal)
Junior Member Username: 95spiderneal Post Number: 149 Registered: 3-2002 |
hans subaru can get 300 out of 2.5l and im not interested how its acheived by cubes, revs or forced induction. bottom line is these are street cars that should be designed to last 75-100k miles with proper maint. im po'd at ferrari and its customers for accepting these excuses | ||
| Scott DeGhetto (Scott63)
Junior Member Username: Scott63 Post Number: 57 Registered: 4-2003 |
Tim, I believe that another f-chatter (Ricky Nardis) had the 95 valve guide problem resolved in 99 (on a 95 car) when FNA stepped in.. You should contact him for more details. Scott | ||
| Hans E. Hansen (4re_gt4)
Intermediate Member Username: 4re_gt4 Post Number: 1379 Registered: 4-2002 |
Actually, 375hp is AMAZING performance out of a 3.5L motor. | ||
| neal (95spiderneal)
Junior Member Username: 95spiderneal Post Number: 148 Registered: 3-2002 |
this thread sickens me about ferrari the co. and keeping with the clinton analogy i feel your pain tim! i needed a total rebuild at 8k mi in 348 because loose cam journal nut fouled oil delivery. there is no excuse for such a situation where the car wears out at 25k mi and the rationalization is because said part leads to better performance. 375 hp is certainly not amazing performance nor is it enough to allow for this type of reliability issue. post this thread in general section so others can be made aware. i love fcars but wonder if they're really worth it when something like this happens. | ||
| arthur chambers (Art355)
Intermediate Member Username: Art355 Post Number: 1812 Registered: 6-2001 |
The bonze guides probably do wear a little quicker, but most of the post 95 units don't have this problem. Perhaps Tim's was run at high RPM for longer periods? Art | ||
| FABS (Caruso360)
New member Username: Caruso360 Post Number: 22 Registered: 5-2003 |
David; I don't believe you are addressing Tim's point in that he purposely stayed clear of the "softer" bronze guide issues and opted to pay more for more "reliability". You're addressing a technical issue that should have been dealt with prior to any purchase so that a "performance" decision could have been made. I believe FNA should still step up to the plate and with some of your help, maybe they would. | ||
| David M. Castelhano (Servizioman)
New member Username: Servizioman Post Number: 14 Registered: 4-2003 |
Tim, like anything else in life there are trade offs when an engineer designs a valve guide. Bronze guides are better for high speed applications and steel guides wear longer. The 355 guide is particularly short compared to many guides and this is done for a reason. The guide does not pertrude down into the corresponding port as far as most other valve guides do. This promotes better "breathing" which translates into performance. Since that it why you buy a Ferrari it is a good thing. From an endurance standpoint it is a bad thing since the valve itself gets less support and is more like to wear the guide than a longer guide. Can't always get Toyota like reliability and Ferrari performance from the same source. Steel guides will wear less but if I were running at high rpms I would prefer bronze. | ||
| FABS (Caruso360)
New member Username: Caruso360 Post Number: 21 Registered: 5-2003 |
With this incident I would be surprised if any one could have piece of mind in any 355 purchase. I was in search of a 95 355 when I discovered this issue with the valve guides. On two separate occasions during negotiations, I insisted that the valve guides be replaced. As you might expect neither party was willing to remedy this problem, hence no '95 355. If Ferrari claims a resolve to the valve guide issue from '96 on and a purchase is made based on the context that the valve guide problem is now a non-issue and in fact it is an issue, and an expensive one at that, then they should step up to the plate. This sounds like a "Clinton like" cover-up. Based on this, any 355 is out of the question unless proof positve valve guide issue has resolve. Keep us posted and Good Luck! | ||
| JRV (Jrvall)
Intermediate Member Username: Jrvall Post Number: 1591 Registered: 11-2002 |
>> And who knows how many "undiagnosed" problem 355's are out there?<< agree...looks like it's going to be a crap shoot. | ||
| david handa (Davehanda)
Member Username: Davehanda Post Number: 814 Registered: 5-2001 |
Sorry Tim, seems you did your homework before the purchase, and I have heard exactly as you. Obviously the next step is to have it properly repaired. Then, perhaps a tactfully worded letter to FNA for assistance...though I wouldn't hold out much hope on that one. I would be curious for others to chime in on what they have heard as well, as I would like to consider a 355 purchase in the next year or two, and was thinking of a 97 or newer. Now what? 1998 or newer? Or did they ever fix this problem? Let's face it, there really aren't all that many 355's of any vintage with over 25k miles on them so it may be hard to tell what the extent of the problem is. And who knows how many "undiagnosed" problem 355's are out there? | ||
| Tim Barnett (Tim_barnett)
New member Username: Tim_barnett Post Number: 26 Registered: 4-2003 |
I own a 1997 355 Berlinetta with 21,500 miles built in January 1997. Recently, I took my car to Dave Helms for its 30K service. Not wanting to take any shortcuts, I selected Dave because he has years of experience as a factory-trained mechanic. When I brought the car in, he thought that it was missing slightly at idle. However a short road test showed the car ran smoothly and had strong power. After the road test, the problem had disappeared and idled smoothly. Unfortunately, a compression check revealed low compression on the #6 cylinder (~110) with a leak on the exhaust side. The low compression report was a little puzzling given that the car ran and sounded great. The preliminary diagnosis was either carbon build up (admittedly unlikely on the exhaust side) or a burned valve. We decided to pull the head. However an examination of the exhaust valves showed them to be in fine condition. Amazingly, it was the valve guides that were severely worn. This on a 1997 model. This was even more puzzling. I�ve read in several sources that the 1995 model year was plagued with soft valve guides, but never on a later model car. Obviously the guides needed to be replaced, however it was troubling that there was no apparent explanation. The rest of the engine showed practically no signs of wear and there was very little carbon buildup anywhere else. Then, on a hunch, Dave went and started scratching one of the valve guides. Turns out they are BRONZE! Just like the '95! Currently my engine is still in pieces and I�m wondering what my next step should be. When I purchased my car over two years ago, I paid a premium, in part, to avoid the �soft� valve guide problem. I would be grateful for any advice or guidance from other FChat members. Thanks, Tim |