w114 engine swap to OEM 617 w/ manual transmission

[jack.stew48]

heyo all,
ive got a beautiful Mercedes 280 75' but the motor is trash and will take a ton of work to get the motor going.. i just keep finding more issues as i work om it.

so, my plan is to swap in a oem617 5cyl. diesel with a manual transmission into it. does anyone know of any clearance issues? or any major issues i might run into? anything helps...

[tom 114-75]

what did you do with this? my same model timing chain broke and the engine was pretty much trash. But I looked for a m110 engine, found one nearby, and it's in. Simple. Ya, I have to chase some things but it's worth it. Stay as original as you can.

Just my humble opinion.

tom

[jack.stew48]

Originally Posted by tom 114-75

what did you do with this? my same model timing chain broke and the engine was pretty much trash. But I looked for a m110 engine, found one nearby, and it's in. Simple. Ya, I have to chase some things but it's worth it. Stay as original as you can.

Just my humble opinion.

tom

that was my plan at first. i love this car and the challenge of working on a gas model (which ive never done) however i have to put a pretty large chunk of change into it just to get it running/buy a new m110. Then i have to deal with the Solex carb, and 15 miles to the gallon.
i have a lot of experience working on the om617s and i love those motors to death so i decided to go that route. trust me i wuish i could keep it original..

[gmog220d]

Benz put a 617 into 300D W115 so there are goodies out there that would make the swap easier. But I think you'd need to use an NA (non turbo) engine, and I think you might need the intake and exhaust manifolds from a W115 300D to get around clearance issues with the body braces that are in the W114/W115 engine bay, intake for sure. The W115 300D air cleaner sits in the RH front corner and is not mounted on top of the manifold like they are in W123 cars. You would also need to supply a vacuum signal for shutting the engine down.

Apart from these issues you'd need a pedal assembly from a stick shift car, or at least the clutch pedal and mounting bar to install into your existing assembly. You'd probably need to have the front section of the driveshaft and shift rods modified to the right lengths. Might look for threads where people have swapped 5 cylinder engines into 4 cylinder W123s to get a sense of all those issues.

If you decide to go for it I've got engine mounting arms and an air filter housing from a W115 300D I'd love to sell, if you need them.

[jack.stew48]

Originally Posted by gmog220d

Benz put a 617 into 300D W115 so there are goodies out there that would make the swap easier. But I think you'd need to use an NA (non turbo) engine, and I think you might need the intake and exhaust manifolds from a W115 300D to get around clearance issues with the body braces that are in the W114/W115 engine bay, intake for sure. The W115 300D air cleaner sits in the RH front corner and is not mounted on top of the manifold like they are in W123 cars. You would also need to supply a vacuum signal for shutting the engine down.

Apart from these issues you'd need a pedal assembly from a stick shift car, or at least the clutch pedal and mounting bar to install into your existing assembly. You'd probably need to have the front section of the driveshaft and shift rods modified to the right lengths. Might look for threads where people have swapped 5 cylinder engines into 4 cylinder W123s to get a sense of all those issues.

If you decide to go for it I've got engine mounting arms and an air filter housing from a W115 300D I'd love to sell, if you need them.

thanks for the info.. do you think a 85' California edition would work in the w114? those have the air filter in the front right like you described. i know for sure im going to have to modify something because the N/A w115 300d engines have the oil filter housing somewhere else.

[gmog220d]

Yeah that oil filter can be a problem. Apparently the earlier W115 617 NA block casting is different where the oil filter housing attaches, so you can't use the earlier canister oil filter on a later W123 617 block. I believe the workaround for a later engine in a W114/W115 is installing an adapter plate with hose fittings to the block and using a remote filter.

The '85 Cali engine is turbo, right?, which opens up another can of worms. I'm pretty sure stock manifold/turbo will not fit under the body brace, and there might be some side clearance issues too due to the relatively narrow space between the frame rails in the W114/W115 engine bay, but I'm guessing about that. I've not done this swap myself hence the "guessing" but have lurked here long enough to have read posts by others who have.

And the flywheel is another thought. Euro W115 300Ds could be had with stick shift, and they came with a heavier flywheel. I saw a thread about one of these cars here not too long ago with pics of that flywheel. I don't think it's necessary to have it, though. I know a guy in Albuquerque who put a 4 speed stick into a W123 NA 300D. He used a flywheel from a 616 and it seems to work fine as the car is regularly driven.

[jack.stew48]

Originally Posted by gmog220d

Yeah that oil filter can be a problem. Apparently the earlier W115 617 NA block casting is different where the oil filter housing attaches, so you can't use the earlier canister oil filter on a later W123 617 block. I believe the workaround for a later engine in a W114/W115 is installing an adapter plate with hose fittings to the block and using a remote filter.

The '85 Cali engine is turbo, right?, which opens up another can of worms. I'm pretty sure stock manifold/turbo will not fit under the body brace, and there might be some side clearance issues too due to the relatively narrow space between the frame rails in the W114/W115 engine bay, but I'm guessing about that. I've not done this swap myself hence the "guessing" but have lurked here long enough to have read posts by others who have.

And the flywheel is another thought. Euro W115 300Ds could be had with stick shift, and they came with a heavier flywheel. I saw a thread about one of these cars here not too long ago with pics of that flywheel. I don't think it's necessary to have it, though. I know a guy in Albuquerque who put a 4 speed stick into a W123 NA 300D. He used a flywheel from a 616 and it seems to work fine as the car is regularly driven.

yes the CA edition is turbo. what i plan to do is try to get it to fit with the turbo, and if not just change the manifolds and downpipe and remove the turbo. i really love the extra power that i get from the turbocharged motor so i really want to make it work.

as for the flywheel, i have done extensive research and i believe it is possible and plausible to use the one from the 240d manual that i am getting got the transmission from (i plan to buy a whole parts car, so i can take the exhaust, and the entire driveline w/ rear diff and axels, that way i wont have to cut the driveshaft)