Timing Belt Service on 550

If you figure it out, would you like a free trip to Fl ? BTW bring your tool.

 

I can't spend your money of course but some things
are best left to the professional. I too am pretty handy
with tools having mechanically restored my own somewhat complicated
British car. But the timing belt procedure is one task I would
not tackle on the 550 just based on what can go wrong if
incorrectly done. Just my $0.02. Perhaps as great a risk
is what else you'll find while you're in there.

Zed

 

This is not a typical timing belt replacement and there are many critical steps that need to be followed. The tension measuring tool that the shop manual refers to is not easily available and costs up to $2000. If the timing is slightly off, or if you make a mistake in setting it, you will need to degree the cams and that becomes even more complicated. The tension of the timing belts is also critical since any fluctuation or incorrect tension will set your check engine light on for a misfire on start-up. Just my opinion, but if you still want to tackle it, good luck.

 

the timing belt service on the 550 is also not very expensive (relatively speaking when compared to say a 355), just let the dealer/professional do it.

 

FBB?

 

The cam pulleys are actually locked together to keep them from moving. The WSMs actually say to do it with a pair of vice grips, but there are more elegant solutions if you do a search here or in tech Q&A.

This is the latest type of tensiometer you will need to set both the timing belt tension and the auxiliary belts tension. It measures the frequency of the belt's vibration once thumped with a screwdriver or other rigid object. Odds are you Porsche mechanic should have access to one. Frequencies for the aux belts (575M) are 160-170 hz for the alternator/AC belt and 120-130 hz for the power steering/waterpump.

You sure you want to do this? You can just do a lock and swap, which is actually pretty simple compared to degreeing the cams.

Make sure you change the tensioner pulleys/bearings at the same time.

Taz
Terry Phillips
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Difficult job - but not terrible. There are some pitfalls to avoid, but if you do your homework, take your time, and pay attention to the details all will be fine. See link below for thread on 456 timing belt service:

http://www.ferrarichat.com/forum/showthread.php?t=265723

 

Dean- Affirmative, and the 550 is actually simpler because of the hydraulic lifters.

Taz
Terry Phillips

 

Yes I'm here. Been there done that. Not a hard job just attension to detail. WSM lays it all out regarding cam timing.

 

That is not a good way to do it hence the industries development of various tensiometers.

 

You can do the job yourself, but what you are missing are they eyes of an experienced technician who knows what to look for and what to check while things are apart. My valve timing was off. We suspect that it was set wrong at the factory. We also found that although the main water line had been replaced, the two small ones had not. The labor rate of a mechanic includes more than the robotic changing of the belts.

 

You can use this tool to lock the cams. The Staeger tensiometer is about $ 2000 and not avaliable to public. Now they have the sonic one that Terry posted for about $2500, Ricambi might carry. Sark
http://www.uktools.com/sealey-vs777-universal-twinquad-diesel-camshaft-locking-tool-p-5607.html?osCsid=040686097201dcd25ccbbbf7a238f546

 

This is the address manufactures the Staeger tensiometer.
http://www.frwilk.com/the944/belttool.htm

 

I am sure you are a talented craftsman however, if money is the issue, don't do it with your buddy. I am just a novice, but remember..., " penny wise- dollar foolish...." leave it to the experienced pros. Your mechanical skills can be applied in less crucial areas of repairs..
Best of luck.

 

http://www.checkline.com/product.php?id=125805&lang=en

http://kscdirect.com/item/GAT%2B7420-0507/GATES%2BCORPORATION_507C%2BSONIC%2BTENSION%2BMETER%250A

http://www.google.com/#q=belt+frequency+meter&hl=en&prmd=ivns&source=univ&tbs=shop:1&tbo=u&sa=X&ei=LbB-Te7IBc6JrQHCmeCCCQ&ved=0CEMQrQQ&bav=on.2,or.r_gc.r_pw.&fp=503ef9a58296c9b1

http://www.toolbay.co.uk/Laser-Tools/VauxhallOpel/4212-Belt-Tension-Gauge.aspx?source=webgains&siteid=73369

http://cgi.ebay.com/Clavis-Type-5-Hand-Held-Belt-Tension-Meter-w-Sensors-/380120583243?pt=LH_DefaultDomain_0&hash=item5880f3cc4b

Taz
Terry Phillips

 

FYI

Taz
Terry Phillips

http://www.ricambiamerica.com/product_info.php?products_id=258751

 

Yes! Don't do that. It is this type of "lack of service" that gives ferraris a bad name. Are you sure you trust the P-bug mechanic or is he a Porsche guy trying to sabatoge another Ferrari? Because this is a great way to do it. There is more to do besides a lock and swap. I guarantee that you will be posting about your "next" 550 failure if you go down this road. There are a lot of parts to remove to get down to the valve covers off the car. There is now great access to many things that require routine service. It is time to do those things when the lot is uncovered. I think you are wasting the time of this brain trust to do a "lock and swap" and I don't think we should be telling you how to screw your car up.

 

Anyone who can change 911 timing chains and set the cam timing is certainly capable of doing a 550's timing belts. Having experience with both, the 550 is much easier...just more parts.

 

FBB- I tend to agree with you, but when you degreed your last set of cams, how did the factory "assembly marks" match up with your timing with the degree wheel? If I remember correctly, your timing efforts matched up perfectly with the factory marks.

This is one of the questions I have asked Brian and would still like to know the answer. It looks like late model Ferrari timing marks are way more accurate than they were in the olden days. I will wait until I hear a blast from Brian on that subject.

Meanwhile, here is the 575M WSM input on how to change cam belts.

Taz
Terry Phillips
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Taz,

Even if a car is just set-up to the assembly marks there is no way to "lock and swap" because the tensioners will pull and the tension will be uneven at all the different contact points of the belt on gears and pullys. So the cam cogs must still be unpinned to even do that job right. So how much more work is it at that point to time the cams? After hours of taking a bunch of parts off to get there and then just getting to the point where you can have inital settings is 95% of the work. That is why still many pro shops secretly slap on belts when under time pressure call it a done job. I have witnessed this with my own eyes. Just a few years ago only a very few on Fchat talked about cam timing and now it is all the rage. Most here would not think of doing this job without cam timing just like many here would not buy a ferrari without a PPI having a leakdown test. The community is getting more sofisticated with time and all that is in the record right here on Fchat. We expect more of the real techs. We diy'ers should be especially careful to do the job right otherwise the real techs on Fchat have every right to call us a bunch of ferrari butchers. As a diy'er for my car to run right don't I have to do the job to the same standard as a real tech? Some will say it's my car and "so there." But those same guys doing the job wrong are *****ing about how their car is unreliable. Sure some ferrari's are more unreliable than others but I have had 4 reliable Ferraris and one of those was the biggest POS ever made the 348!

 

FBB- When you had a car that had to have the valve clearances adjusted, you were going to have to remove the cam covers at the very least to do that job. Beginning with the 355 and 550, all the cars have hydraulic valve lifters and one of the main reasons for removing the cam covers is gone. If you do not have leaks, the covers do not need to be removed.

I was a rabid degree the cams guy until I asked Brian Crall and Dave Helms if they degreed the cams on every belt change. They said no, once the initial degreeing had been done, there was no need to do it every time the belts were changed. If the factory marks are accurate, which they were on your last car, there is less reason to degree the cams.

My last belt change was a lock and swap done by Bobileff in 2008, and my car runs like a top. Plus look at what the factory WSM says. Now I listen to Brian, who says a lot of Ferrari tech data is worth considerably less than the paper upon which it was printed, but this is not exactly rocket science. I do not think a lock and swap is a mortal sin on late model Ferraris.

Taz
Terry Phillips

 

First paragraph I disagree. You have to remove the covers so that you can unpin the camcogs to even do an assembly mark job. You can't see the cam mark or the cam cap mark without the covers off.

Second paragraph is an I agree if your factory marks = proper cam timing. But even if you degree the cams and then you know the timing is right how do you now swap that belt and make sure the cams have not moved? You still have to unpin the cogs to do this job to deal with the uneven belt pressures over the cogs and pullys. If you keep a set timing which you have no marks for you must pin the camshafts by using a tool or what I always do which is to use matchbook covers under the cam caps BUT you could still have belt stretch and motor wear which now makes your old timing wrong. How wrong? I don't know. And you still need to bring the motor to TDC as a matter of good safe practice which is part of the first step to degreeing your cams anyway. So to me there is no good reason to not do the whole job.

third paragraph I think lock and swap is a mortal sin. Maybe L&S means something different to you and me. You see to me it is absoultely critical that when the tensioner tensions it does so over the entire belt. If you Lock then the tensioner only tensions between 2 cogs and the tensioner. What about the rest of the belt? What about the piece of belt between the cam cogs? The cogs must be loose so that the tensioner can pull and rotate the cogs so tension from the tensioner is felt as even as possible over the entire belt length. Does that make sence? So you need to lock the camshaft but not the cogs. What I see as L&S are people locking the cogs with camshaft still pinned or marking with nail polish and then swaping a belt . At that point your timing is anywhere and the belt is not properly tensioned even if a steager or HZ meter is used.

 

Beginning with the 355/550 the cam timing became highly critical due to the tweaked nature of the engine tune. If one wants the Cats to live a long happy life, that timing best be spot on.

Stated in the proper context, once I have personally degreed the cams, then I will do a L&S for a few services before doing the cam timing again. For the record, the last 550 I did had the marks so far off I degreed the cams 3 times on one bank thinking I had a brain fade problem. Prior to the timing being done the marks lined up and this one was a Virgin set by the factory. After the timing was done the marks were a good width and a half off on two cams. The owner thought it ran perfectly before... based on what baseline?

This last 550 in the shop had two quick belt changes done prior to the current owner getting the car. The belt tension had been set by the std spring tension or by someone following the WSM.... either way is wrought with problems, both set the belt tension too tight. In this case it took out both lower drive bearings and had the fences on the drive gears a few hundred miles from breaking off ala the 348's. We pulled the files on the last 6 550's in, reviewing all of our notes, everyone of them had signs of the belts set too tight at the last service. In another year we should know if our research and the settings we came up with work to my satisfaction, they vary a good deal from the printed spec's.

The 550's are a VERY forgiving model but they can only take so much for so long. Tip over enough rocks and look close enough and it becomes quite clear. Fatso helped to identify yet another gremlin lurking on the 456/550's that I believe we now have a solution for. Another week in the toaster oven should verify we have that problem solved.