Started the conversion yesterday - PeachParts Mercedes-Benz Forum

123euroowner · #1 08-16-2009, 08:48 AM

So far Im in the beginning steps of my 4 speed conversion using a 300D 4 speed. I started dismantling the drive line, haven't taken the trans out yet. I got the parts car outside and Its in sorry shape! It does have a few nice features like manual a/c controls, orthopedic drivers seat, M pump and other typical euro goodies. What I was curious about was what I should change before I install the trans in my car? And the proper way to remove the 300D flywheel?

Thank you guys for your input! I will be junking this car so if theres any parts requests just post away!

nhdoc · #2 08-16-2009, 09:02 AM

The problem is that you need to balance the flywheel to the engine you are transplanting it to. In theory each flywheel is balanced for its own engine, at least that is what we have been told. Your old one is balanced for the engine it is attached to and the new one for its engine.

Logically if you can match the new flywheel to the old one's balance and install it in the same position as the old one came out then you should be OK. That would mean marking the orientation of the old flywheel on the crank and then bringing it and the new one to a machine shop which can match the new one to the old one and mark the new one with the same position as the old one had been removed at (they will probably drill some holes to remove weight at some locations). Of course there's also the question as to whether the balance should be done with the clutch assembly attached or without it. Doing it without assumes the clutch assembly is neutral...but then it also assumes the torque convertor on the old engine was neutral balanced too.

Or...you could simply bolt the new flywheel and clutch to the old engine and hope for the best, which is what most people would do, but it is not the "correct" way.

If it were mine, I would seriously consider transplanting the engine and tranny and settling for a N/A 300D rather than the turbo...that would eliminate the need to worry about rebalancing the flywheel.

lutzTD · #3 08-16-2009, 09:08 AM

any good machine shop can match balance. or if they dont want to match have them both nuetral balanced, then transfer the old flywheel balance to the new flywheel yourself by measuringand recreating the balance holes from the old to the new

123euroowner · #4 08-16-2009, 09:15 AM

O ok. I dont know if it makes a difference, but Im working with a 300D flywheel already. I was thinking, If I were to set the engine to TDC, mark the flywheel with a chisel, and set the new engine to TDC and install accordingly, would that suffice?

lietuviai · #5 08-16-2009, 11:15 AM

I got lucky with my flywheels on my conversion. Both were neutral.

nhdoc · #6 08-16-2009, 12:06 PM

Quote:

Originally Posted by 123euroowner

O ok. I dont know if it makes a difference, but Im working with a 300D flywheel already. I was thinking, If I were to set the engine to TDC, mark the flywheel with a chisel, and set the new engine to TDC and install accordingly, would that suffice?

No, read my post carefully, the flywheels are balanced to the engine they are mated to. Doing that is no better than just swapping them from one engine to the other. You might be lucky and they will be close enough, but the correct way to do it is to have them matched and then install the new one.

t walgamuth · #7 08-16-2009, 03:41 PM

By way of elaboration of the explanation. I believe that most flywheels are neutrally balanced but some (in my case one out of four) will not balance neutrally because the crank will not. In that case the flywheel is used to make a crank/ flywheel unit neutral. To be sure mark both your flywheels to the cranks they come from and have them both checked. If the flywheel from the engine you want to use is not neutral then the new flywheel must be balanced to match that flywheel and bolted to the crank in the same place.

You don't want to guess on this because if you happen to get one that is not neutral and have a mismatch it will shake your teeth loose. It is not worth the risk since the only solution is to remove it all and do it right the second time.

Good luck, most of them are neutral.

bigblockchev · #8 08-16-2009, 07:16 PM

I have yet to hear of someone who had a problem with installing a flywheel on a conversion and later had to remove it to rebalance or had vibration problems. I have read several posts of folks who used gasser flywheels and the like and had good results. This leads me to believe that mercedes flywheels are neutral balanced regardless of their origin. If someone has objective evidence to the contrary please pipe up. I find the speculation confusing. I have built high performance gas engines for over 30 years and usually there is clear direction from the manufacturer as to whether the particular engine requires external balancing or not. Please learn me about mercedes. Cheers Dan

t walgamuth · #9 08-16-2009, 09:57 PM

It is in the factory service manual.

We're not making this up.

I had one which was not neutrally balanced....my 280e euro.

123euroowner · #10 08-17-2009, 02:46 PM

So basically I should get them out, checked and matched if needed?

Stevo · #11 08-17-2009, 06:16 PM

Quote:

Originally Posted by 123euroowner

So basically I should get them out, checked and matched if needed?

I have swapped several 616 FWs and have found that if the crank and/or the FW DON"T have witness marks (which was the case in all but one swap) they will not need balancing. Beware, the "marks' are not easy to see however.

t walgamuth · #12 08-17-2009, 08:09 PM

Still an excellent idea to mark before removing.

Yes my 280e had witness marks but they were so subtle that you would not have believed they were anything.