Block Differences

[Raffaelli]

So I've done some research on the plethora of different m119s that mb built. Im trying trying to make sense of them all.

So my car has a 4.2L .975.

I'm undecided on buying a 5.0L, resealing it and bolting it in. OR buying a 5.0 M119 builder engine, finding a m117 5.6 crank and getting custom pistons and building such an engine.

Option one- I gather Id look for an engine out of a S class or SL. I think the numbers I would look for would be a 5.0 .970 or .972. Since the 500Es are super rare, id doubt id find a .974 at a pick and pull.

The .960 is to be avoided if im correct. different deck height causes a bunch of problems.
The .971 and .975 I believe are 4.2L.

Im not sure where a later .980 engine fits in compatibility wise. Accessories, intake, valve covers obviously different, but I think it would bolt in easily.

Option two- Im curious if anyone knows if the stroked m119s were based on only the .960 tall deck blocks, or brabus or who-ever did it on short decks too. Id like to get a newer 5.0 short deck engine if I can, stroke it and enjoy.

Its a lot of info, I hope someone can help. Ive built custom engines before and its not foreign to me, but these m119s have a bunch of variations in them. Thanks for the help.

 

[lowman]

is it actually correct that the m119 engine in the E500E...is different "height" compared to the other m119 5litres?
There is a myth that the engine is "lower"..or something
I have also heard about this dude who got a quote on changing the timing chain..and they got the wrong chain,as it was to long for the E500E m119 engine?

any views on this..

and sorry if i interrupt your thread Mister Raffaelli.

 

[gsxr]

I'm undecided on buying a 5.0L, resealing it and bolting it in. OR buying a 5.0 M119 builder engine, finding a m117 5.6 crank and getting custom pistons and building such an engine.

Forget building a stroker unless you have DEEP pockets.

Option one- I gather Id look for an engine out of a S class or SL. I think the numbers I would look for would be a 5.0 .970 or .972. Since the 500Es are super rare, id doubt id find a .974 at a pick and pull.

Find a .972, this is nearly identical to the .974 and is 100% bolt-in... yes, it will take some more effort to locate one. Forget the .970, despite the fact you will probably find one free in your back yard.

The .960 is to be avoided if im correct. different deck height causes a bunch of problems.

Correct. Don't even think about it for a 400E/E420.

The .971 and .975 I believe are 4.2L.

Yes.

Im not sure where a later .980 engine fits in compatibility wise. Accessories, intake, valve covers obviously different, but I think it would bolt in easily.

The block will bolt in, but as you noted, everything up top is different... the .980 is only a possibility if you plan to use standalone engine management (see stroker comment about deep pockets).

Option two- Im curious if anyone knows if the stroked m119s were based on only the .960 tall deck blocks, or brabus or who-ever did it on short decks too. Id like to get a newer 5.0 short deck engine if I can, stroke it and enjoy.

500E stroker engines are based on the standard .974 "short deck" engine. But only a closed-deck block, which was used until very early 1994 USA model year only. All .98x engines are open-deck. If you want to attempt a stroker M119 for use in a 400E/E420, you need a 1992-1993 .972/.974 donor engine. (The .970 becomes an option if you really do bore/stroke, since the oil pan/pump all has to come off anyway).

Its a lot of info, I hope someone can help. Ive built custom engines before and its not foreign to me, but these m119s have a bunch of variations in them. Thanks for the help.

Have you built custom Alusil engines before? Bit different work involved with the etching/lapping process needed for the walls. I wouldn't use sleeves. Search the forum, some of this has been discussed ad nauseum in the past.


Seriously - the easiest and cheapest upgrade here will be getting a .972 engine and dropping that into your .034 with the 5.0 LH and EZL. I've heard people talk about building stroker engines for 10+ years but nobody has actually done it, that I'm aware of...

 

[gsxr]

is it actually correct that the m119 engine in the E500E...is different "height" compared to the other m119 5litres? There is a myth that the engine is "lower".

The 119.960 engine with CIS-E mechanical injection used in the 1990-1992 500SL was a "tall deck" engine, and yes it is higher, and all the internal parts are different... including probably a longer timing chain.

All the 119.97x/.98x are "short deck" engines. The 500E DOES NOT have a different/special engine/block compared to any other .97x engine.

 

[Raffaelli]

Awesome, thanks for the info GSXR.

One more quick question, the .970 is out of an SL and the .972 is an S Class, correct? And what makes it a pain to swap? Upper oil pan? Other little things like accessories and timing covers?

 

[gsxr]

One more quick question, the .970 is out of an SL and the .972 is an S Class, correct?

No, the other way around... .970 is W140/S-class, .972 is R129/SL-class.

And what makes it a pain to swap? Upper oil pan? Other little things like accessories and timing covers?

The upper oil pan, pump, and pickup are the nuisances. Don't screw up the gasket/sealing or you may end up pulling the engine to re-seal it. Timing covers and accessories are all the same. The exhaust manifold are different but you can swap those from your .975 motor. Again, with a .972 you avoid all this work. The only way I'd touch a .970 is if it was already a 6-liter... then it would be worth the hassle to swap the parts around.

 

[8899]

There was a forum member who recently had to replace his engine. The thread is around here somewhere....but a lot of this discussion was covered in that thread as well.

 

[lowman]

what does this "open deck" "short deck" term mean?

and with the engine numbers...does this mean that all the 124 v8"s has the "less tall" engine?

 

[Glen]

what does this "open deck" "short deck" term mean?

and with the engine numbers...does this mean that all the 124 v8"s has the "less tall" engine?

Short deck refers to all 119.97x and newer blocks. All W124 V8's use short deck blocks.

Open deck refers to the mounting surface where the cylinder head bolts onto the block. I think a couple pictures will explain it best.

1st picture is an open deck block.
2nd is a closed deck block.

 

[lowman]

Short deck refers to all 119.97x and newer blocks. All W124 V8's use short deck blocks.

Open deck refers to the mounting surface where the cylinder head bolts onto the block. I think a couple pictures will explain it best.

1st picture is an open deck block.
2nd is a closed deck block.

ahhh now i see.that makes sense.did not understand the english term,but now i understand

cheers.

 

[500AMM]

Short deck refers to all 119.97x and newer blocks. All W124 V8's use short deck blocks.

Open deck refers to the mounting surface where the cylinder head bolts onto the block. I think a couple pictures will explain it best.

1st picture is an open deck block.
2nd is a closed deck block.

Thanks for posting, Glen. Illustrative pics! :idea:

As for closed deck vs. open deck - some years ago I read that MB went away from closed deck blocks due to risk for sand residuals left from the casting process. It was a demanding process to clean the castings properly inside to avoid sand ruin of the engines.

I've also read that the closed deck block is more rigid and withstand flex better than the open deck. This is a known issue when it comes to tuning and high loads on alu.blocks. I think all M119 race engines were closed deck?
It would be nice if some "MB-masters" like Klink can prove/disprove this statements.


-a-

 

[Raffaelli]

I forgot about this thread. Ended up buying this little gem for $400. Out of a 93 SL. Even had a starter on it. I need to pull the heads off and do a refresh. No time for a stroker, my 4.2 in the car burned a valve...

 

[gsxr]

I forgot about this thread. Ended up buying this little gem for $400. Out of a 93 SL. Even had a starter on it. I need to pull the heads off and do a refresh. No time for a stroker, my 4.2 in the car burned a valve...

Unless you know for sure that there is a valve problem, I would not pull the heads... HUGE amount of work, and all the gaskets required get expensive fast. Clean it up, do an external re-seal (front crank seal, cam solenoids, P/S pump seal/hoses, valve cover gaskets, PCV hoses, lower oil pan, oil lever sender O-ring, yadda yadda) and drop it in as-is. You'll get an idea of the internal condition after you pull the valve cover and oil pan.

If you've done M119 head gaskets before and know what you're getting into, great, go for it!

 

[samiam44]

"As for closed deck vs. open deck - some years ago I read that MB went away from closed deck blocks due to risk for sand residuals left from the casting process. It was a demanding process to clean the castings properly inside to avoid sand ruin of the engines."

I can be corrected, but I'm 99% sure these are not sand castings. The surface finish looks like investment casting or some other molding technology. Closed deck had a high scrap rate ~20% due to defects. They lowered manufacturing cost by reducing the % which failed inspection.


M