355 flywheel rebuilding?

Never mind, I thought maybe they maybe were back and duh miss read the date of the post.

 

MD clutched retired and closed their doors over a year ago. I bought flywheel and rebuild kits right at the end. You can get Kluber from ebay.

https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=kluber+grease&_sacat=0

 

Which is the correct grease? That link shows lots of different part numbers. Can you tell us which grease you got from MD?
It would have been great if MD sold their technology to someone like Hill.

 

https://www.ferrarichat.com/forum/posts/141451617/

You can see it on the label here.
https://www.ricambiamerica.com/70000789-kluber-grease.html

KLÜBER GLK 1301
https://www.ebay.com/itm/175104422261?hash=item28c5097175:g:iD0AAOSwi0RXxK0Q

I used this thing called Google just now. I say got for it and do it, if you find the large oring post the part number, pretty sure McmasterCarr has it. just need the dimension. It will be 6mm or so less than the one you pull off.

 

Apologies for bringing back up an old thread but I have searched through the forums for answers to a question that was apparently not asked yet : when rebuilding an F355 DMF, has anyone managed to source replacement springs? These must soften up over the long term in the same way as springs on a regular clutch disc?

 

I don't think spring fatigue would be of concern.

 

After rebuilding the flywheel on my F355 using the 195g grease pack supplied by superformance (and replacing the clutch, etc) the rattle when turning the engine off is still there.

There is conflicting information posted on here on the amount of grease that should be used, some saying that adding more than the specified amount in the WSM helped against the rattle whilst others said it made it worse. At this stage it makes sense to me that no matter the amount of grease applied, the flywheel will always rattle if the 4 internal springs have lost their original stiffness, which they should as their function is to replace the springs otherwise normally found on a standard clutch disc.

Opinions?

 

There are spring manufacturers who will make you some custom springs for reasonable money here in the UK. Not sure where you are based but there must be similar businesses close to you.

 

Yes there are, but I'm frankly stumped that no one on here seems to have ever questioned the replacement of flywheel springs. I'm beginning to have regrets not dumping that DMF malarkey and replace it with a single mass flywheel.

 

I seem to remember Andrew at MD Clutches producing a short run of single mass flywheels and finding improved performance and no loss in drivability. I know he's shut up shop, but might be worth contacting him to find out if he has any old inventory knocking around.

 

I had a close look at pictures of his SMF and I believe it is made by the same company that supplies Hill Engineering with the reinforced standard flywheel plate. I already asked them for a quote but I'm not really willing to lose the inertia allowed but the heavy-ish standard DMF, as I think the balance between torque and throttle response will be hard to improve for road use.

 

A couple of months ago I helped a friend rebuild the dual mass flywheel for his single plate clutch 348. While reassembling the flywheel I discovered something that I have never seen discussed. I think I have discovered why the grease in the flywheel gets contaminated with gear oil.

While the triple seals on the propeller shaft are a key component in helping to keep the gear oil inside the geabox, they still fail over time. As a result gear oil will travel the length of the propeller shaft, due to the centrifugal force of the shaft spinning, and then end up at the input hole for the flywheel. This is my theory of how, and where, the gear oil gets into the flywheel.

When the flywheel is disassembled you will discover a puck/disc inside the hole where the splines of the propeller shaft fit inside flywheel. The puck is on the backside of the flywheel where the ring nut gets screwed in. That puck is what the set screw, in the middle if the ring nut, presses against when it is tightened down to help lock the ring nut in place.

Now here is what I discovered.
The puck has a lip around it so that it can be dropped in place. However, there is nothing sealing it off. It is only be pressed against the metal. So my theory is that over time the gear oil works it’s way past that puck and into the flywheel, contaminating the grease, causing it to liquify, and then work it’s way past the o-rings. (Which is another point of failure).

So what I did was to put a small amount of sealant (I like Hondabond HT) inside the little ridge/lip of the puck before I dropped it back on the hole. I only put just enough Hondabond around the ridge/lip of the puck so that it would seal, but not so much that it would squish out everywhere when the lock screw was tightened down. I also made sure that both the puck and the hole were completely free of oil/grease before I applied the Hondabond. I used break cleaner to clean the surfaces.

It has only been a couple of months since I did this. So time will tell if this did or did not work.

 

The other thing is the material of the o-rings.
Because the o-rings are black rubber I assume they are made from Buna. Buna does not hold up well to oil nor heat. Because of this the o-rings fail over time. This will also lead to the flywheel grease getting past the o-rings, and getting flung all over the place.

It is my opinon that the o-rings should be made from Viton rubber. Viton holds up very well to oil and heat. You can tell rubber is made from Viton because it typically has a brown color to it.

 

I'll read it later Im sleeping right now

HAPPY HAPPY !!!!!

 

Timo,

I have not repacked one of these in a while. The springs don't wear out the plastic parts do from rattling and rubbing without grease. You are more likely to have rattle from the plastic than because of the springs. I'm not sure how the kluber grease is supplied today but the WSM said 185 or 195Gr of grease. I can't remember. But the cans came 500 grams. I always put 250 grams and it solved the problem and I had 1/2 a can left for the next time. I also on my 348 racecar lightened the flywheel assembly by cutting out the spider thing and welding the unit. I took it to a shop to spin balance it and I raced my 348 for several years like that. There was no felt extra NHV or harmonics that damaged the input shaft. I raced that car pretty hard and it is still being run by an Fchater as an Auto-X racer today. So a solid conversion can be done and the gearbox will take it because I raced it harder than anyone is going to do on the street.

 

I have seen Viton rings coloured Brown, Green and Black before
It is superior to Buna N
In my 348TS there was a spillage of gearbox oil so I changed the rings several times
This did not help
It turned out that the leak was from the flywheel grease mixed with gear oil
due to failed maintenance by the PO

 

I have also seen green, black, and blue. The green o-rings I have used for A/C lines in a car. The blue and black Viton I have seen for rubber gloves. So yes they come in various colors. Regardless of the color, it is my opinion that the o-rings for the flywheel should be made out of Viton and NOT Buna.

But the main thing I wanted to point out is, to make sure that the little puck has a small amount of sealant at the base of it. Where it mates to the flywheel, to make sure that it seals, and help prevent any gear oil from getting past and into the flywheel.

 

It appears that sealing of the puck will only prevent the gearbox oil from reaching the rear flywheel bearing and the chamber under the bearing cap (I have marked the puck in red on the flywheel/clutch cross section). The gearbox oil is already in the flywheel area before it passes the puck.

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It is true that the gearbox oil, when the triple seals fail, can travel all the way to the rear flywheel bearing, contaminating the clutch discs and the flywheel grease on the way. When I did work on my 348 clutch for the first time (soon after I bought the car), the chamber under the rear bearing cover was full of (clean looking) gearbox oil which, of course, also "lubricated" the clutch discs and diluted the flywheel grease.

So, I think it's the triple seals that (should) prevent the gearbox oil from visiting the flywheel.

 

Well, let me put it this way.

It won’t hurt anything to put a little bit of sealant around that puck.