| Author |
Message |
F-J'87EuroTR (Ferrarijoe)
| | Posted on Wednesday, November 21, 2001 - 9:41 pm: | |
Kurt,
What you have said does make since and I understand what you mean. The reason I think that the cooling circuit is block, and I apologize for not mentioning before, the oil temp never gets over 70F or 23.8C. Does this help any?
Joe |
Kurt Kjelgaard (Kurtk328)
| | Posted on Tuesday, November 20, 2001 - 11:52 am: | |
Correction:
If the oil passage is obstructed, the valve piston will not move - this because of the lack of differential pressure as discussed earlier in this thread.
Anyway - the pressure in the motor lubrication system will still be too high. If the return passage is completely blocked, no oil returns to the pump, the oil pressure will in effect be totally unregulated and only dependent on pump output volume, which vary with engine RPM.
Did I create more confusion than enlightenment?
Sometimes it is easy to confuse even yourself. |
Kurt Kjelgaard (Kurtk328)
| | Posted on Tuesday, November 20, 2001 - 2:18 am: | |
I am referring to the motor lubrication system.
The oil that is relieved (you could say "tapped" from the volume produced by the pump to keep the pressure down) by the pressure relief valve is led back to the pump via a short oil passage. If this oil passage is plugged, no oil would return to the pump, even if the pressure relief valve would be fully open and thereby keeping up the pressure.
However, as I said earlier, I find it not very likely. The passage has a diameter of a little finger.
I am certain that you have a problem with the valve assembly. It sounds as if the piston is sticking in the bore for some reason.
Any increase in friction between the piston and bronce liner will add to the force induced by the spring and thereby producing a higher pressure in the main system. |
F-J'87EuroTR (Ferrarijoe)
| | Posted on Friday, November 16, 2001 - 11:28 am: | |
First of all thanks Steve for posting the diagram. I did remove the oil filter housing when the problem originally happened and found nothing to indicate a blockage.
And Ed, I removed the sump cover, checked for any foreign debris and replaced the pressure relief valve and spring with new ones and nothing changed.
Finally, Kurt this sounds like a good test and I have not tried it yet. But what are you referring to in the return oil way? The cooling or the motor lubrication system?
Thanks all of you for your responses, Joe Duch |
Kurt Kjelgaard (Kurtk328)
| | Posted on Friday, November 16, 2001 - 9:14 am: | |
With a correctly working relief valve, the only blockage that could induce too high a pressure would be a blockage in the return oilway from the valve to the pump.
However, I consider this not very probable.
Try to reassemble the pressure relief valve without the plunger and spring - start the engine and observe the oil pressure.
If zero or very close to zero, there is no blockage in the return oilway - the oil simply runs right back to the pump.
Only run the engine long enough to be sure that no pressure is building up - a few seconds should do it!!
If you have pressure indication, varying with RPM, then you would have a blockage in the return oilway.
As I said I don't think it is very likely - I go with Edward. |
Edward Gault (Irfgt)
| | Posted on Thursday, November 15, 2001 - 10:02 pm: | |
The problem almost has to be in the main pump pressure relief valve, sticking or installed incorrectly. The pictures are not really too clear and a picture of the pump and valve would be a big help. I have never seen a case of too much pressure when the cause was anything other than the pressure relief valve. |
Steve Magnusson (91tr)
| | Posted on Thursday, November 15, 2001 - 8:25 pm: | |
Here's a jpeg of the TR oiling system:
http://albums.photopoint.com/j/View?u=972829&a=10846708&p=56426661
Joe D. -- I'd still say I don't see how it would be possible for any blockage in the yellow inlet areas to cause your over-pressure problem. IMHO, the blockage must be somewhere in the (red) outlet side of the main pump -- have you tried removing the oil filter support (125824) just to have a look around? |
Edward Gault (Irfgt)
| | Posted on Wednesday, November 14, 2001 - 8:40 pm: | |
If you have some pictures of the oiling system and could post them or send them I can diagnose your problem. |
F-J'87EuroTR (Ferrarijoe)
| | Posted on Wednesday, November 14, 2001 - 7:29 pm: | |
Magoo,
The reason I suspect this is, I think that if the cooling circuit (2nd pump) were blocked between the pump and the return to the motor via the condenser and sump, it would over-pressurize the motor cooling/lubricating pump (1st pump). I know there is a bypass valve on both pumps, but I'm not sure how or if they are connected with each other. You�re right, there are a lot of ifs. I have asked several "experts" and they are clueless.
Help, Joe Duch |
magoo (Magoo)
| | Posted on Tuesday, November 13, 2001 - 11:15 pm: | |
Joe, I certainly will not have your answer but there are "ifs" in your question. The question that comes to my mind is there a reason you suspect this? Depending where the restriction would be could cause a irregular oil pressure in my opinion. |
F-J'87EuroTR (Ferrarijoe)
| | Posted on Tuesday, November 13, 2001 - 5:23 pm: | |
OK,
I'm back to try another theory on the high oil pressure problem (please read earlier input). Is it possible that if there was an obstruction in the oil cooling circuit i.e. factory casting, or a wadded paper towel piece accidentally left in and then dislodged from the crank case hose breather fitting after a re-furbish and painting of the air filter housing insulation. If this were to happen, would it not impede the flow of oil to the oil cooling condenser and over-pressurize the primary circuit? If it did, wouldn�t this explain the oil squirting out from the �O� ring seal of the oil filter and from the front main crank case seal, or would it? I would appreciate some fresh input to this theory and if you can prove it wrong, at least I can eliminate this possible cause.
Thanks, Joe Duch |
KARL DASTOLI (Luch)
| | Posted on Monday, June 25, 2001 - 6:13 pm: | |
Joe,
As for the oil pump cover, the bronze bushing can be bored out and replaced with C932 bearing bronze. I have done many similar projects and could do it if you need it. It's simply a matter of warming the casting to @ 250 deg F and shrink fitting the new bronze in and the boring it to size. I have all the machines to do this easily.
LUCH |
Joseph Duch TR87 (Ferrarijoe)
| | Posted on Wednesday, May 30, 2001 - 7:21 am: | |
Steve,
I did try as you suggested, leaving the oil tank cap/stick off after a warm up and unfortunately the high pressure is still there. All along I have been thinking that I may have some kind of obstruction in the cooling system. Maybe in the area of the oil tank and possibly the screen at the bottom of it. Is it possible that the mesh screen may have deteriorated and collapsed? Does anybody support this idea and would I have to remove the motor to get the tank out to inspect it?
Thank, Joe |
Kurt Kjelgaard (Kurtk328)
| | Posted on Tuesday, May 29, 2001 - 12:27 pm: | |
Steve - I see what you mean. We mean the same, just with different words. The essence is, that the pressure on the back side of the plunger should be zero or very close to zero.
It should be if the pump is just gravity fed from the oil tank (or in the case of a wet sump, sucks the oil from the bottom of the oil pan).
I am not English (or American for that matter), so I your wording confused me.
brgds Kurt |
Steve Magnusson (91tr)
| | Posted on Tuesday, May 29, 2001 - 10:10 am: | |
Kurt -- I think a pump can be designed either way (i.e., the forces/flow acting on the relief valve mechanism can be output-to-atmosphere or output-to-input). We may be arguing about semantics -- if the pump input pressure is "0" (which it should be in this case -- see discussion below) then the two configurations produce the same result.
Joe -- Please accept my apology as I made a logic error previously -- I forgot that the oil tank should be vented into the airbox which would keep the main delivery oil pump input pressure near "0" regardless of what the scavenging pump is doing. Although this may provide another thing to check -- try removing the oil tank cap with the engine running just to make sure that the sump is not being "pressurized" (i.e., confirm that the sump is vented OK). You may be forced to just keep digging deeper -- like removing the oil filter support #43 to check for obstructions, trying to probe the main oil gallery, etc.. |
Kurt Kjelgaard (Kurtk328)
| | Posted on Tuesday, May 29, 2001 - 2:09 am: | |
Steve, I don't understand how the pressure relief valve only responds to differential pressure.
The object of regulating the pressure must be to keep the system (downstream) pressure within certain limits and not to keep output pressure relative to pump input pressure. Or did I misunderstand something?
As I mentioned in an earlier posting, pumps do not produce pressure, only volume. Pressure is produced by restrictions downstream of the pump, intentional or unintentional.
If the valve regulates the system pressure by "measuring" and regulating the downstream pressure, the high pressure could be caused by a restriction in the return oilway from the pressure regulator back to the pump. If the regulator cannot get rid of the excess volume of oil that is producing this high pressure, then you would have a situation like the one Joe describes.
brgds Kurt |
Joseph Duch TR87 (Ferrarijoe)
| | Posted on Monday, May 28, 2001 - 5:08 pm: | |
Well, hello everyone. I did work on the car Saturday and found out a couple of things.
The problem with high oil pressure is still there. I removed the sump cover and both take up tubes. Then had a friend turn the motor over to observed the gears of the pumps turning, which they did. This at least tells me that the coupler linking the separate pump gears isn't broke.
I removed both pressure relief valves and as it turns out, I did leave the new tapered plunger (chamfered front end) for the main pump in when I tried to fix it last summer. I have about 1500 miles on the car since then and I guess if it was going to brake in it would have by now.
I replaced the ball and spring relief valve for the scavenge pump since I bought it.
So I am back to square one and hoping that the ideas will come pouring in again.
A Ferrari 1-2 was enough to keep me in good spirits though.
Thanks, Joe |
Ben Lobenstein 90 TR (Benjet)
| | Posted on Wednesday, May 23, 2001 - 10:17 pm: | |
We'll all be here awaiting to hear the results of your weekend's endevours....Good Luck!
-Ben |
Joseph Duch (Ferrarijoe)
| | Posted on Wednesday, May 23, 2001 - 10:05 pm: | |
Hey guys,
I ordered the pressure relief valve and spring Steve along with a sump cover gasket today. I still have the new plunger and spring Kurt, I kept them in the oiled bag. I will install them all this weekend.
I would like to think you all for your immediately responses and the great insight. This is the first time I have used this site. It has swiftly shown me the true worth of owning a Ferrari and the passion they inspire.
Lets keep our hopes up with my car and think of the Scuderia this weekend at Monaco. Forza Ferrari!
Thanks, Joe
BTW. I live in Olympia Washington, USA. |
Steve Magnusson (91tr)
| | Posted on Wednesday, May 23, 2001 - 2:58 pm: | |
Ooops -- should be page C5 not C6. |
Steve Magnusson (91tr)
| | Posted on Wednesday, May 23, 2001 - 9:42 am: | |
Joe -- Check that the pressure relief valve on the scavenging pump housing is OK (items 6,7,8 in Fig 6 on page C6 of my TR WSM; also items 60-65 on Tav.23 in the TR SPC). If this (crude) relief valve is stuck closed or blocked, the scavenging pumps will "oversupply" the main oil pump. The pressure relief valve on the main pump won't even open since it only responds to differences in pressure between the main input and main output (i.e., if they are both high, it's a happy camper). Just a thought... |
Kurt Kjelgaard (Kurtk328)
| | Posted on Wednesday, May 23, 2001 - 7:10 am: | |
Joe, as I mentioned it did take some for the pressure to stabilize at the normal setting, which for a 328 is about 6.25 kg/cm2 (multiply with 14.7 to get PSI) at 6000 RPM.
The idle pressure is of course lower as discussed in an earlier thread.
Maybe you should try the new, modified piston and spring for a while and avoid going too high on the RPM's? In my case, there was no immediate lowering of the pressure - my first thought was that this was BS. But my Ferrari mechanic (who is an expert on these cars) assured me that results would come. And they did.
By the way, oil being blown by the main crankshaft seal usually indicates overpressure in the crank case.
brgds Kurt |
Joseph Duch (Ferrarijoe)
| | Posted on Wednesday, May 23, 2001 - 6:51 am: | |
I want to thank you three for your responses and I will answer your questions.
Ben,
I have owned the car since July 1999.
I did check the pressure with a gauge that I attached to where the oil pressure sending unit is placed on the oil filter housing and it also read high.
I flushed it with kerosene by attaching a fitting to the inlet oil port to the motor after removing the oil filter housing and I back-flushed the cooling system.
I did not notice the normal copper coloring of a oil additive like Slick-50.
Also, after putting a new UFI filter, a new plunger and spring for the pressure relief valve (I checked for any burring on the surface of the plunger bushing), I still blew oil by the main seal the first time I took it out and reved past 4500 RPM's. I went back to the old plunger and spring because with the new ones the pressure was not only less on start-up and idle (3-4 bar or 44-59 psi), the pressure still shot up and oil blew by. Because of this, I'm positive it is not the sending unit or the gauge.
Kurt, I did notice a difference in the new plunger and spring which, according to the numbers where the correct ones, the plunger did have a more beveled top and the spring was 5mm shorter.
BTW. The motor would have to come out and the gearbox detached in order to get to the pump!
Lets keep plugging away at this please. I am starting to get new ideas and that's a good thing!
Joe |
Kurt Kjelgaard (Kurtk328)
| | Posted on Wednesday, May 23, 2001 - 3:53 am: | |
Hi Joe,
I have a 328 that had a similar increase in oilpressure. From 6 kg/cm2 to above 9kg. This also blew some oil seals and ruined my clutch.
I found that the bronze bushing, in which the piston in the pressure relief valve is moving, was worn at one side where the front (opposite the spring) of the piston is working.
The wear was very difficult to see, but could be felt with a finger.
Actually a trained Ferrari mechanic never saw it, but suggested that a blockage might exist somewhere in the system. A thought I found a little farfetched. Well, the wear made the piston "tilt" a little bit and increased the friction and thereby relieving only at a much higher pressure.
The bronze bushing is an integral part of the oil pump cover, which in turn is mated to the engine block itself. So in effect, changing the bushing means changing the entire block.
The solution is to buy a new piston (and a new spring while you are at it). The newer piston is modified and has a chamfered front end (I wish i had a picture).
After I fitted this, the oilpressure returned to normal within a few hundred kilometers of driving.
This was last year and the oilpressure has behaved perfectly since. Cost - Piston:500 FFR approx. 70 USD, spring 20 FFR 2.50 USD (plus, of course, repair of oilseals and clutch at authorized Ferrari shop, 11.000 FFR approx. 1500 USD ).
As I said, this was a 328 - I don't know if this applies to your car, but it is worth a try.
Good luck
brgds Kurt |
Warren E. Smith (Magoo)
| | Posted on Tuesday, May 22, 2001 - 11:02 pm: | |
Ben, I was thinking the same thing about the sending unit that went under high revs. Could this all be linked together with the faulty gasket problem UFI is having, discussed here on the chat line. It may be in the archives by now. I agree, first things first. MAGOO |
Ben Lobenstein 90 TR (Benjet)
| | Posted on Tuesday, May 22, 2001 - 10:53 pm: | |
I have a few questions for you Joe:
1)Have you owned this car from day one?
2)Have you checked this oil pressure number with a secondary pressure guage?
3)What do you mean flushed, and with what?
Here is why I'm asking, I like to rule out things that could be suspect in order to help solve the true problem. If you didn't own the car since day one, a previous owner may have added to the oil some kind of additive (Slick 50 or the like) that tend to block or clog oil gallies. I have heard of this on other engines, so I wouldn't rule it out as a possibility, unless you know the full history.
Secondly the UFI filter could have just given up as a freak accident (possibly??) and then if you haven't checked the high pressure reading with an outside meter then it could always be the car's oil pressure guage or sending unit.
Then we can get to pumps and actual oil systems.
-Ben |
Joseph Duch (Ferrarijoe)
| | Posted on Tuesday, May 22, 2001 - 9:03 pm: | |
I have a Euro-spec F113B motor with a high oil pressure problem.
It initially started while under hard acceleration in which the oil (Castrol Syntex) suddenly blew-by the front main seal and the oil filter (UFI). I was towed home. I cleaned up the car and replaced the filter and oil and discovered a higher than normal oil pressure after a warm up. While setting still or driving and if I rev over 4500 RPM's the pressure reaches the 12 bar line (176 psi.).
I removed the sump cover, checked for any foreign debris and replaced the pressure relief valve and spring and nothing changed. I then removed all the oil lines and the oil filter housing to check for a possible casting piece that Giancarlo may have missed in Sept. '86. I also flushed the whole system but there was nothing I could find that would indicate an obstruction.
From what I can see in the manuals, the pump is in three stages:
1. The pump section nearest the sprocket supplies the motor.
2. The middle section circulates the oil through the cooling system.
3. The end section is an auxiliary of some kind?
I have asked several people what they thought but haven't found a solution. If you could make any suggestions or know someone who could help, I would appreciate it.
Thank you, Joe |
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