potential parts car for manual transmission swap

[SW]

I am contemplating the purchase of a complete grey market 300D (non turbo) with a manual transmission. The owner claims that the car was running fine until one day when they could not get the transmission to shift out of 4th gear. Afterwards, the owner did not attempt to fix the car and parked it in the back yard for approx. 2 years. One thing that bothers me is that the shifter has been misplaced.

I’d like to purchase the car so that I can swap the manual transmission and all related parts into my recently acquired ’83 300D turbodiesel. However, I’m skeptical about the transmission and shifter. Could a problem with the shifter have caused the trans to be stuck in 4th gear? What do you guys think? I’m going to see the car tomorrow, any tips, tricks, or advice on what to look for will be appreciated.

[leathermang]

but I am going to say it anyway...

A stick shift is not a good match for a turbo diesel engine.


There is are several reasons that MB did not make turbo engined stick shift cars.

[bgkast]

Have you ever driven a turbo with a 4 speed? It drives like every other Mercedes 4 speed. Seems like a fine match to me.


The shifter linkage could have been the problem but when you are bargaining for a price assume the transmission may need a rebuild. It should not be hard to find a replacement shifter assembly as the 4 speeds are common in 240Ds. It will be nice to have a flywheel from a 617 for this conversion as it will give a slightly smoother idle than the 616 flywheel that most (including myself) use in this conversion.



Edit: Didn't the C 111 have a turbo 617 with a manualy transmission? Granted it was porbably not the same transmission used in the W123, but the factory seemed to think it was a good idea. The main reason IMO that they did not offer the turbo/manual combo is that nobody wanted to have to shift their $35K car.

Originally Posted by leathermang

There is are several reasons that MB did not make turbo engined stick shift cars.

Such as????? The only reason I can figure they didn't off it is because there were marketed as luxury cars in the USA. The trend in the 80's was moving towards laziness, I mean convenience, and they wanted to put it in gear and go.

You didn't say how much the guy wants for the car. It could be as simple as loose/broken/bent linkage in the shifter. Or, on the other end of the scale, you may have to open up the tranny to get it out of gear. It's hard to say without actually looking at the car.

[leathermang]

I am going to play along....

lets say that in the US the reason is that people did not want to shift their $35,000 cars..

So why did they not offer it in Europe ?
Those people LOVE to shift expensive automobiles...

[SW]

Thanks for the replies. $500 is the asking price. I think its a good deal, but it would be a great deal if the trans and shifter were working properly. If necessary, I can find a trans locally for under $300.

[bgkast]

Originally Posted by leathermang

I am going to play along....

lets say that in the US the reason is that people did not want to shift their $35,000 cars..

So why did they not offer it in Europe ?
Those people LOVE to shift expensive automobiles...

I don't think that the turbo engine was available in Europe.

[H-townbenzoboy]

Originally Posted by bgkast

I don't think that the turbo engine was available in Europe.

It was available in the 300TD, but none of them had manual transmissions either.

[Parrot of Doom]

Loads of turbodiesels over here, most of them have manual gearboxes. Most people in the UK drive a manual.

[leathermang]

Originally Posted by bgkast

I don't think that the turbo engine was available in Europe.

That is what I said...

so why did they not offer a turbo stick in Europe ?

It has to do with the clutch and rpm that the turbo starts to work at..

if you use an automatic on a gas carb engine then it eats up gas when you floor it..
but flooring a diesel auto does not have nearly that effect....because it only affects the governor.... it does not have an accelerator pump .. only the proper amount of fuel per power stroke is delivered...
so if you have a stick and engage at a normal rpm which is easy on the clutch wear then you have put a load on the engine when it is not in its power making curve. Which means that you get to the next stop light slower than using an auto with a preset stall speed matching the turbo characteristics ( or you change out manual clutches way too often )...

A Diesel with Turbo is the most efficient engine combination... and it happens that an auto matched to it does not have many drawbacks .... putting a stick only gives people something to play with and play ' race driver' with their 120 hp 3500 lb car.... and due to the spooling properties either makes it slower overall...or wears out the clutch lining too fast relative to a normally aspirated diesel engine clutch...

Yes, the turbo lag can be an issue. With MB being required to follow emissions limits, they could not tune it properly to reduce lag.

The individual is free to do what they wish with their car. That lets us be free to tailor the engine performance characteristics the way we want.

Now, ponder this: R Leo, bgkast, and I have all done this conversion. None of us have given it a bad review. We have all praised it and how well it performs.

If this combination were so bad, why are we not putting it down as well?

[leathermang]

Originally Posted by ForcedInduction

Now, ponder this: R Leo, bgkast, and I have all done this conversion. None of us have given it a bad review. We have all praised it and how well it performs.

If this combination were so bad, why are we not putting it down as well?

Now ponder this... someone spends a lot time or money doing something... tells everyone they know they did it... then , even though they are not thrilled with the results , they don't run around hollaring about how bad it turned out... that would be the very first time something like that ever happened ... right ? LOL

Anyway, there is at least one elephant in the room...

1) How soon are people going to have to change out the clutch ? That depends on how they drive... if they are willing to live with the lag/clutch engagement situation it may not affect them... but that does not mean that the situation does not have its drawbacks... and it seems like someone should mention the possibility to someone thinking about putting in the work and money necessary to make this change so they can think about it first...

Anyway, if you are old enough to remember when drag racers actually shifted their cars themselves....and then people like B and M Hydro started beating them... they were shocked at first... then they got automatics themselves ...because the same physics are in play.... needing higher rpm ( without having to change out the clutch each run ) to be in the power band before engaging the load on the engine... think of a turbo diesel as a regular diesel with a racing cam... the effects are the same in terms of the power band and how to best utilize it...

[JimmyL]

Originally Posted by leathermang

putting a stick only gives people something to play with and play ' race driver' with their 120 hp 3500 lb car....

So, is it a bad thing that I play race car driver with my 67hp 3500 lb car???

So you are saying Randy or somebody else does not like the conversion but has not told many people about it?

"think of a turbo diesel as a regular diesel with a racing cam" It's a 32hp increase from it's N/A version. Only a 37% increase in output. It's not at all like a racing cam. N/A engines want gear ratios close together to keep the RPM's high into the power band. Turbo engines are more happy with ratios farther apart to let the extra power from the turbo do it's job.

Clutch life is directly related to temperature and how much slippage it sees. If a 240D with about 1/2 the power and even less torque needs to slip the clutch alot every day just to get going, why can that clutch last 20+ years and 200,000+ miles? It makes sense to me that having more torque allows me to engage the clutch sooner. Less slipping, less heat, less wear. I often have my clutch fully engaged before 1200rpm, I don't slip it when changing gears, and I don't downshift unless I'm going to accelerate again.

[Icefire]

Im doing the manual swap right now, If I dont like it, ill post so. ok...