Sorry to hear about the cam drive bearings- unfortunately Verell and I know quite a bit about them. I posted the above mentioned post, and agree that if your outer bearings are not completely failed, then just replace the outers. Not much more work than a standard belt service. From your description, yours don't sound too bad. One of mine, on the other hand, was totally destroyed. The noise did not change with engine temp and the cam drive gear was visibly jumping around as the car idled. My car could not be driven like it was without fear of jumping a few teeth on the timing belt. There was no question about what was making this clattering noise. If it were up to me, the outer bearing replacement would be part of any 30K service on 308's and 328's. Even the older 308's with outer oil seals. If put in the same situation, I would decide the same as I did then- replace all four bearings. We originally were just going to pull the timing case by pulling studs, but a stud snapped and our decision was made for us- out came the engine. It was quite an adventure, and I learned way too much about my car and it's running perfectly now. In the end, I have a completely serviced engine and the knowledge to do it again if I had to. Hopefully, not in the near future! I have a nice simple brake system rebuild to look forward to this winter... If you or your mechanic have any questions, there are many great people on this site that can and will help. Good luck- jwise
My mechanic is a longtime Ferrari pro, so I think he knows all the tricks. They are indeed the two outside bearings as shown in the diagram above. Unfortunately, as of late this afternoon, the balancer still won't come off the shaft. Hopefully a weekend with spray lubricant at work will loosen it up and he can finish the repair on Monday.
but don't heat it too much because the rubber in the damper will not like it... Jwise, glad to hear the bearing job was successful after your marathon post. I remember you said it still had the slight ticking noise and I've always wondered, did it just fade away?? Richard
Yep- after about 400 miles. Another factor, speaking of dampers, was the degree wheel we rubber cemented to the damper to accurately time the engine. I didn't think anything of it at the time, but decided to remove it after about a month of driving. The noise was still there at the time, but not really detectable without a stethescope. So, I put the car on stands and figured I would just scrape it all off while the car was running. There was some glue in the factory balance holes in the face of the damper. I scraped off the wheel, glue, and residue in the hole, and the noise was gone forever. I had no idea that that damper was that accurately balance- makes sense now in hindsight. I attached a photo of the failed bearing and the offending degree wheel. Image Unavailable, Please Login Image Unavailable, Please Login
It is interesting reading all these posts... I am currently working on a 1938 Mercedes 230 that had a terrible knocking sound above 1500 rpm. Given that there are not many "experts" on these cars, we (the owner and I) decided it would be safer to pull the engine and strip it down. We are now on the stages of reassembly. The noise turned out to be a destroyed generator that really only made noise once the revs were up. Since the generator sits right next to where the valves are (it's a sidevalve) it was a toss up between the gen and a broken valve spring. So, the generator got repaired for $130, thanks to ASOM auto electric in LA. The rest of the engine looks fine, except for the leaking water pump, blown head gasket, and corroded thermostat housing. I guess what I am trying to say is that there is no harm in pulling the engine and stripping it when you are uncertain as to what is going on, as once you do this and put it all back together, you'll at least know the thing inside out. The big GOTCHA is the cost of having someone else do this. If you can do it yourself, then it is a great learning experience, but if you are paying someone else, then you need to be rady for a BIG bill. Just my .02
I've noticed that now the temperature is now in the 50's in the a.m., that upon startup I too get an erratic "clicking" noise. It's not constant, as slightly increasing RPM's don't cause the clicking to speed up syncronized to the engine RPM.. they are more like random "clicks".. .almost like a sloppy valve clearance, but those increase in speed when the engine RPM's increase. I am thinking from what I have read, that I might have this accessory belt clicking phenomenum, but want to make sure... Once the engine has warmed up about 2 minutes (sometimes less) the clicks are gone and don't come back at all while the engine is warm. Any direction is greatly appreciated.
Look at this thread.. http://ferrarichat.com/forum/showthread.php?t=43663&highlight=328 Hope it helps. Ciao Eugenio
To finish the story: It was one of the lower cam drive bearings, specifically the one for the aft bank of cylinders. Both of them were worn, one more than the other. I had the mechanic do the timing-belt-&-tensioner-bearing service, though he admitted that the parts probably would have lasted until the 60,000 mile service, which is about 4,000 miles (and 9 months) away. Driving the car home was a revelation: the engine hasn't sounded that good in the 21 months I've owned the car! Thanks, everyone, for your opinions and advice. Now, I have to see if the car will pass emissions (which it did last year), since the same mechanic thinks the catalytic converter is breaking down internally. If it fails, Hyperflow, here I come!
P.S. He got the harmonic balancer off, with some more pulling, sometime Monday morning. The mating surfaces had quite a bit of surface corrosion, but neither the balancer nor the crankshaft was damaged. He indicated that he thoroughly cleaned the mating surfaces and lubricated the joint well when putting the balancer back on the shaft (apparently not done the last time the balancer was removed).
Trust me, I dont think they would have lasted, the bearing usually breaks and the cage disentigrates making the gear thrash around. On the early cars the cage falls into the oil pan. I would be worried that it could even skip a tooth or at the very least the gears would grind against eacxh other
Jim......... great news. And yea, whenever I pull a balancer off I always take a fine 3M Scotch pad (about 1000grit) with a fine oil and clean the surfaces inside the balancer, crankshaft, and keyway groove, along with the balancer itself. These are almost a pressed fit and there is no room for error or dirt. Always reinstall with a balancer special install tool that ensures it goes on square. (plus just cleaning balancer is good to do in-itself). How's that song go............"On the road again...................."
