1998 550 Maranello "sorting" thread--DIY

John...the bearings were placed in exactly as they came out, with the SKF lettering and identification to the inside of the timing cover.

Now that I have pretty much verified that my bearings are toast, disassembly of the timing cover can begin. Again.

Step 1: Inspect the key slots to make sure that there is no deformation or evidence that the keys were wiggling. None found (Photo 1)

Step 2: Remove the snap rings from the front side of the bearings (Photo 2)

Step 3: Pop the caps off the bearing. You will essentially destroy the bearing in the process of removing the gilmer drive shafts from it. Once the cap is removed, you will see the plastic ball cage (Photo 3)
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Pete! I got a great idea. Can you send me the old failed bearings. I would like to give them to my aerospace bearing rebuilder to see what he can come up with. The guy is super creative and the inovator of the reiner bearing we use in 348 gearboxes. I use him to rebuild Ferrari wheel bearings because these bearings are so expensive. If he can rebuild them perhaps that is the answer. Rebuilding bearings is what he does and I have used him for 20 years.

 

Carl, you mean these damn things? (Photo 1)

I will fish them out of the trash tomorrow....
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Step 4: Take a straight slot screwdriver and pry out the plastic cage, and this is what you are left with. (Photo 1) The bearing is now ready to accept the Draper removal tool.

The Draper removal tool is the best way to remove the shaft from the inner race of the bearing. I made a homemade version last time I did this but now I have the genuine article (Photo 2) Spray a little PB blaster on the shaft and let it run down into the inner race of the bearing, and then gently press the shafts out of the bearing.

Once the shafts are removed and set aside, you can remove the rear snap rings and spring washers and press out the bearings from the timing cover. They slide out very easily. (Photo 3)
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Pete, it looks like they still had plenty of grease, so the premature wearing of the bearing wasn't due to oil coming through the seal and contaminating/diluting the grease.

 

Hi John,
which modified are to do for install the bearing that 3.6 mm more width?
i imagine those 3.6 mm you found inside the carter reducing the ring spacer between bearing and gear? Exactly?
The increased C, C0 and Pu, will do a longer durability ...
For me is a very good modification!

 

John, the grease inside the bearing that failed prematurely appeared to be a bit "soupy". Hard to tell if that was the PB Blaster I was using to remove the shaft or if it was oil contamination.

My package arrived Saturday. I will advise...

 

Fabio, that is exactly it, then the position of the cam gear must be adjusted since it locates on the rear face of the inner race of the bearing.

Thanks Pete, if that inner seal with the garter looks to be in bad shape, perhaps you did have some oil contamination?

I did not get the through bolts out to you as promised; I had a domestic emergency this weekend (leaking kitchen sink) that wifey insisted I sort out before any car stuff.

 

Pete, et al:

No expert, but have had the front cover off at 18K miles with the original bearings... No rust or grease leakage and no play with the cover on. With the cover off, there was some play (don't exactly recall how much, but don't think it was as much as in the video)... I concluded that was normal. This is essentially a shaft with ball-bearings in races at each end.... with one end free there's going to be some play...NO???

IIRC, John and I discussed this, and with no perfect replacements available, the thought was, "Go with the Devil you know..."

On refit, there was no play in the fenced-cogs with the cover on and all is well...

Mark

 

Mark,
Because of how I reinstalled the cover last time (explained earlier in this thread), I did not have a chance to examine any play with the shafts inside the bearings without the gilmer gears being engaged with the crank gear.

This time around, I am going to press the bearings into the cover and then press the gilmer gears into the bearings, and reinstall the cover and gears as a unit. I will check and see if there is play in the inner race of the new bearings, and if so how much. It will be a nice comparison piece for next major.

 

Received my "noname" 170787 from Algar today. As I looked them over, I noticed some subtle differences between them and the old SKF bearings. The new bearings look "lower" quality and where the old SKF had a rounded outer race edge, these have much less of a rounded edge to them. It makes them harder to put in.

I baked my timing cover at 225 degrees F for 30 minutes and then attempted to "drop" the bearings in. They don't go in that way. They still had to be put in the way the last set were, gently tapped into their seats with my bearing hammer set (Photo 1)

Once the snap rings are in place, this is the appearance of the bearings (Photo 2)

I hate this part of the job. These bearings are such a PITA to get in, and the snap rings are difficult, gotta center the rear spacer ring, etc. Hate it. I sure hope these last.
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I'm getting ready to pull my cams, so I thought I'd try to get some shots of the elusive rear timing marks that Taz and others often talk about.
I have never looked for mine before, but was pleasantly surprised to find that my car has them AND they line up from the last major I did. (Photos 1 and 2)

I can't imagine that one would ever set the timing using these marks. They are imprecise looking, like someone took a punch and just scribed a dent into the cam cap and camshaft. I imagine I will use them only as a backup verification once I have degreed the cams the usual way.
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I went ahead and rebuilt my tensioners with new springs, end nuts, and shaft pins. (Photo 1)

The new springs were almost a centimeter longer than the old ones.
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Pete-Is the wire gauge size on the new springs the same as the old? It almost looks like the wire gauge size is smaller on the new spring.

 

Agreed! And the parallax issue and access makes it nearly impossible to site them in. You will also fine that if you time the Ferrari way that moving the cog 2 pin positions the rear or front marks will not appear to move while 2 cog holes is a big number change on the dial gauge.

 

Picture makes the inner and out race look bigger and the gap between smaller. Will a draper fit in there to get those out next time?

 

Pete- Those springs do not do anything after the tension is set, do they?

 

Carl...stay tuned. More tonight.

Terry... No, they just stay in constant compression I believe.

 

Pete, just want to say that the really excellent pictures you take along with the detailed narrative (plus all the FBB, Taz, etc. comments) makes learning about maintaining these cars a real pleasure for noobs. Really feel like I can do a decent job when belt time comes around. Hopefully the less-than-ideal bearing situation will have improved by then. Thanks.

 

I purchased an extra 170787 just to rip apart, and here are some comparison photos between it and the "old" SKF version

They are very similar, with only minor differences to the naked eye. The retaining spring is slightly larger diameter (of the coil winding) than the old SKF. The new bearing has a smooth rear cap mating surface, with ridges in the SKF.
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I hate to interject, but didn't feel like my question warranted a new thread and all the smart-guys are in this one anyway.

On the coolant expansion tank, there is an overflow hose. Where should the hose go? I need to change my battery and just want to ensure I put that back in the correct location once I move the tank and shield out the way.

Thanks in advance to the 550 brain trust!

-Joe

 

No magic place. Needs to be routed directly downward inside the rear of the front wheel well so that the coolant gets dumped out onto the ground.

 

Hm, probably showing my ignorance here, but I thought single row, deep trough bearings like that generally had more balls in them. Seems it would make the bearing able to handle higher loads, like only seven balls would allow the inner race to 'rock' slightly inside the outer race, compared to if it had more balls in it. Or wear out faster due to the higher load on each ball. To take the analogy to an extreme, what if only four balls were in there--there would be times during the bearing's rotation that the balls were all spaced on one side, which would surely be a bad thing. To a lesser case with seven balls, but nevertheless?

 

Will, the gaps look a little exaggerated because Pete removed the cages from both bearings for the pic. The cage keeps the balls centered and spaced.

 

Duh, yeah, forgot about the spacer. Probably more balls wouldn't fit, not that simple. Thanks John.