Fabricate om617 manual flywheel?

[wstetson3]

I spoke to a guy who owns a machine shop today. He makes some stuff for military applications. Anyway, I asked if he could make a flywheel for a manual transmission so I could use it on my Merc. He said he would need tech drawings or an actual flywheel but he didn't see why not. Has this been done? I have seem it discussed but never done. Any thoughts?

[Partscarver]

Start with a 28# 240D flywheel as a pattern
realize that you need to finish at 38#
it will take time and that costs $

[t walgamuth]

There has been some discussion of it here. I know I have. I imagine if you search under my name and using 300D flywheel you can find lots.

[JB3]

Its not the technical skill of doing, its the cost and return on investment that often maks such projects prohibitive.

For instance you start with the small crowd who wants a manual in their 35 year old car with a certain engine. Then you pare down that crowd to the group within who have a problem with a 28lb factory flywheel. This is after you wade through all the posters who tell you such conversions are impossible with zero practical knowledge of it.

That becomes a very small market, meaning you are looking at a costly one off for a custom flywheel. No doubt the machinist can make it, but its going to cost more than sourcing a rare 38lb flywheel.
Forum member winmutt bought a brand new 38lb flywheel from mercedes not that long ago, maybe a few years back for less than you would expect. Id PM him for info on how he bought it to see if any more are still available

[Dan Stokes]

I have the 240D flywheel behind the 617 in the race truck and there is no noticeable vibration associated with it - and I spend most of my time at WOR and at high RPM. I think the whole flywheel deal is overblown, probably by the guys who claim that you have to run Mercedes air in your tires or the whole car will blow up.

Dan

[vstech]

the 38lb deal is most important for idle, and city driving... racers often use aluminum lightweight flywheels... not exactly an apples to apples comparison...

[vstech]

I have one in my euro car that's for sale by the way...

[t walgamuth]

If you never drove a Mercedes stick with the 38# flywheel you'd never give it a thought, but with the heavy fw the 617 idles like a six cylinder and is astonishingly smooth when revving up. The 617 has a pronounced hop at idle with the automatic which has a much lighter "fw" mass.

My favorite machinist thinks he could mill a shoulder on the 240 fw and slip over a heavier lip using temp diff and do it for not too much money.

[Dan Stokes]

Mine idles fine, too. Maybe it could be MORE refined but it would certainly be a subtle improvement that few could actually notice.

Dan

[vstech]

Originally Posted by Dan Stokes

Mine idles fine, too. Maybe it could be MORE refined but it would certainly be a subtle improvement that few could actually notice.

Dan

that's impressive. maybe the weight is not needed? hard to know.

[t walgamuth]

Originally Posted by Dan Stokes

Mine idles fine, too. Maybe it could be MORE refined but it would certainly be a subtle improvement that few could actually notice.

Dan

Like I said, have you driven one with the 38# FW? If not you cannot imagine the difference. With the correct fw the engine is positively creamy smooth (if that is a possible concept with a diesel!!)

[winmutt]

You could always just buy one for the dealer?

Cost is going to be about the same either way.

[Dan Stokes]

Originally Posted by t walgamuth

Like I said, have you driven one with the 38# FW? If not you cannot imagine the difference. With the correct fw the engine is positively creamy smooth (if that is a possible concept with a diesel!!)

Never met one with the heavy FW but it would have to be a pretty subtle difference! And for a race truck mine is more than acceptable. Actually, it's kind of disappointing how smooth it is - absolutely un-race-car like. Maybe I can mess with the timing 'till it idles like crap (and slows down).

Dan

[Diesel911]

By itself a big chunk of forged Metal to make a whole new flywheel from would have a hefty price.

The adapter ring idea has is less machining to pay for and less metal to buy.

Another way to go would be if you live somewhere where they have a really excellent Trade School that would take the job on as a project.

The School would no where to get the Material and they often get it wholesale.

As with any student project there is a chance it could get messed up but normally in the Instructor makes it good.

[vstech]

Hey dan... did you balance anything in the motor?