308/328/Mondial Timing belt replacement tutorial

Hi Gang,
OK, I wrote a timing belt replacement tutorial. It has taken a substantial amount of time, and it is a work in progress. Suggestions for improvement are welcome.

http://www.birdman308.com/service/timing_belt/timing_belt_procedure.htm

Before you look at it there are several things to say:

1. Yes, the car in the pics is filthy. It was from when I first got my car.
2. No, this is not a recommended procedure...Ferrari says you need to do a full major, not just a belt change. However there are instances in my opinion, where a belt change is a viable option. (i.e. when the car has travelled minimal miles since the last major and the belts need changing due to age, and the valves likely do not need adjusting, etc.) Please don't flame me if you disagree. If you disagree, don't read the tutorial.
3. DISCLAIMER: I am totally unqualified to write the tutorial, but nobody else would do it. Keep that in mind if you try it yourself. "Wrench at your own risk!"

Birdman

 

Very NICE!!

Only one question...if the cams are locked in place why is there any need to mark the old belt and transfer markings from the old belt to the new one? If the cams don't move and the crank doesn't move the new belts can be installed without any regard for belt alignment. Certainly can't hurt to make the marks but I can't see how it helps. I certainly understand that the cams should be marked to ensure nothing moved but I don't understand the belt.

But in any case, superb documentation!

 

Ferrari has never said you need to do a full major and not just a belt job. The dealers do.

Ferrari has long considered a belt job a seperate job. The major was specified at 30k miles. The belts at 3 years or 30k miles. Can be done in conjunction with a major or not.

No reason whatsoever to do a major every 3 years and it has never been Ferrari's position.

 

Wow, Jonathan, it's the Holy Grail of 308 DIY procedures!!!!

AWESOME AWESOME AWESOME work!!! Thank you!!!!!

 

Awesome write up with Pics. IMHO, a thread like this WITH PICS is a great way to do a write up!!!!
Well done.

JIM

 

Excellent tutorial and timely as well! The car I'm looking at fits the criteria you mentioned. In this case, engine-out full service 6 years ago but driven only 4500 miles since.

 

Birdman, as usual, you have done an excellent job. I have already book marked your site for my belt change.

Question:

The procedure assumes that the old belt was correctly placed. How do I double check that it is correct and it is not off by one tooth? I don't see any markings on the camshaft pulleys.

 

Birdman,
You are a true asset to this board.

 

Very, very nice. Makes me think even I could pull this off(!)

 

Its fun, easy and rewarding! You'll wonder why you would ever pay a dealer to change belts/tensioners again!

JIM

 

There's more than a tooth's work of slack taken up by the tensioner. It's very very easy to be off a tooth in the long section between the leftmost cam gear & the cam drive gear & have things look right(been there). Also, you usually have to rotate something (ie: the crank if the cams are locked) a small amount to get the belt to slip into place, again, a potential way to end up off a tooth(been there 2).

The engine is NOT completely locked in place by the 5th gear/park brake, the drive train has about 20 -30 crankshaft degrees of slack that simply cannot be removed. Best you can do it to ensure that when the engine is on PM1-4, the slack is in one known direction, thus the engine can't rotate in the other direction past PM1-4.

BOTTOM LINE:
The marks are your only insurance against very easy to make mistakes.

 

What Verell said: as a sanity check to be sure you are right on.

Thank you Brian for the clarification. As you know, we get guys on here all the time bashing people who just want to change the belts on a car that has gone 5 years and 3,000 miles since the major.

You can't, at least on an early 308 like mine. (I'm not actually sure if there are reliable timing marks on the 4 V cams outside the cam covers, but I don't think so). If there is ANY possibility that the cams are not right, you should pull the cam covers and check. Once you are there, might as well check the valve clearances. Then the NEXT TIME you can change the belts without pulling the covers.

Thanks Joe!

Birdman

 

Incidentally, for those of you with experience in this procedure (Brian!!) I welcome suggestions and or additional pictures to make this procedure better.

Birdman

 

Great job Jonathan!
So what is the giudeline then for checking the vales? 7k, 15k??

 

Further question, related to marking the belts. I have never done this on a Ferrari so forgive me...

On all other engines I have worked on there are timing marks on the drive gears to align to replace the belt/chain. So there is really no need to actually mark anything as long as the engine is rotated so number 1 cyl is at TDC on the compression stroke before starting work - the cam and crank pulley marks will be aligned. Then, it doesn't matter what you do or whether you lock the cam in place or not, you just ensure all the marks are appropriately aligned when you install the new chain/belt.

I'm assuming, by the posts, that the cam timing marks are NOT visible on the engine unless the cam covers are pulled, is that correct?

 

Thank you. I am so happy to see a pro make that statement.

 

Bravissimo, Grazie Mille!!

Another link for my library!!

Brilliant work.

 

Thank you Jonathan, the procedure is save in my favorites.

 

There is a complete 30k write up here, just with out the photos for those wishing to go further.

http://www.camerafilters.com/ec/timing.htm

Also, he has what you might call a 3rd option for tensioning the belts
"- Install the belts such that the teeth that were in contact with the drive pulleys are in the same positions as the removed belt just removed. The belt can be removed and remounted at this point to facilitate alignment of the camshafts, but do not apply the tensioner at this time.

- Keep in mind that when you apply the tensioner, and the belt tension "evens out" the cam index marks will move a few degrees. To compensate for this, what I do is to align the marks as best as possible. Then I release the belt tensioners to apply tensioner pressure and then lock them down again. Now turn the engine *clockwise* (slowly, by hand) two full revs and bring the PM 1-4 into alignment. Don't overshoot the PM 1-4, since you won't want to turn the engine backwards. If you do overshoot, go around two more revs.

- Now, if all is well, all the alignment marks will be nice and even (PM 1-4 and all four cams). I use an extendable mirror to read the forward cam indexes. If the alignments on any cam shaft is not dead-on, there are two possible ways to realign them. Usually a combination of these methods is required if the former alignment wasn't perfect. "


also in your write up here

"METHOD #2 (Ferrari's procedure)
First, you remove the cam locks entirely so the engine is free to spin. Now, using your socket wrench on the crank balancer bolt, turn the engine over while watching the tensioners. As the engine turns, the cams create more and less load on the belts at various times as the lobes run over the valves. As a result, at times there is more tension on the belt, pushing the tensioner back against it's spring. At other times, there is less tension on the belt, allowing the spring in the tensioner to push in further. Watch the movement of the tensioner bearing as you turn, and find the place in the rotation of the engine where the tensioner is pushing in the most on the belt. Stop the engine there, and torque down the tensioner to 41 ft-lbs. (5.6 Kgm). Now do the other bank. "

Be more consistent in the terms you use. You using "more tension on the belt, pushing the tensioner back against it's spring;there is less tension on the belt, allowing the spring in the tensioner to push in further; tensioner is pushing in the most on the belt"

You're using 3-descriptions for two movements and I'm not 100% clear on what is what (to me, it sounds like the first two say the same thing - push tensioner back against spring and allow spring in the tensioner to push in further - but I think you mean two different things here). Pick two and be consistent.

Also, don't use it/in etc. Describe the part (belt, spring, tensioner). It/In/That could mean one noun or the other. Be clear.

see below

"METHOD #2 (Ferrari's procedure)
First, you remove the cam locks entirely so the engine is free to spin. Now, using your socket wrench on the crank balancer bolt, turn the engine over while watching the tensioners. As the engine turns, the cams create more and less load on the belts at various times as the lobes run over the valves. As a result, at times there is more tension on the belt, pushing the tensioner back against it's spring. At other times, there is less tension on the belt, allowing the spring in the tensioner to push out further against the belt. Watch the movement of the tensioner bearing as you turn, and find the place in the rotation of the engine where the tensioner is pushing out the furthest against the belt. Stop the engine there, and torque down the tensioner to 41 ft-lbs. (5.6 Kgm). Now do the other bank. "

 

No one has ever published any kind of tutorial on these cars belts replacement. Ever. Nice to see people come out to give suggestions, but those could have been suggested long ago. Good job Jon.

 

Thanks Paul!

Sean, you are right....that is a little confusing how I wrote that. I'll fix it.

Jonathan

 

Thank you for that.

A few questions:


Why did you put marks on the old belts? Was this to fall back on them if you needed to reuse as a reference point? How did you get the marks on the new belts to line up with the marks on the pulley? Do you hold the new belts up to the old and put the marks in the same place.

What are the shims for the A/C? Are they adjustable or are they just washers?

Do you need a torque wrench for the bolt holding the tensioner? thread lock?

 

Jonathan,I dont think I read it in your write up but is it correct to release the tension on the tensioner by loosening the nut,prying the tensioner spring then re tightening the nut?Also is it absolutely neccessary to remove the water pipe or can the job be done with it in place?I will be doing this soon and this write up is great.I will be making up a set of cam locks out of timber.Would it be possible to give some dimensions for us lazy people who dont want to measure?Thanks and thanks for the write up.

 

The shims are just like thick washes and they are there to align the A/C compressor pulley

 

Thanks so much for the post. This is one of the biggest questions I had before I got my car. Even though I have not decided if I should do my belts myself or have a Ferrari mechanic do it sometime in the future, it is a great reference to help me make the decision.

I do have a question to all those of you that are much more experienced in this area. I was under the impression that at the same time you do the belts, it is best to also do the cam seals ( along with bearings and belts). I know that it is included in the 30k service, along with valve adjustment and valve timing.

So, in my case, the cars 30k service (actual miles 27k) in 2004 and with going with the "basic 5 year rule", I am due this year. All the services on my car have been done by a Ferrari dealer since new. But the car still only has 34k on it, but is driven weekly most of the year.

The question is should I just do the belts/bearings, and/or seals or just have it all done?

Confused in Oregon?

Bob

PS. Weather has been great this week and I have been able to drive my 328, still have a huge grin when I start it.... stays on the face until after it is in the garage ;-)