blown head gasket? rebuild?

[nrthrngreaser]

Hi guys, I'm new here, but have spent a lot of time at the yahoo MB group.

I've an 83 300d that I just fired up for the first time this spring and promptly ran it out of coolant (don't ask) I think blew the head gasket. car was a beater and the engine didn't run well, but the engine was going to be given new rings, sleeves, a valve job, and dropped into a nice 85 300sd with a thrown rod that I'll be acquiring in a few weeks.

questions: how difficult is it to do the rings and cylinder sleeves in this engine, can I do it without removing the crank? do I need any fancy tools to remove and replace the cylinder sleeves?

obviously the head gasket won't be a problem any more, as it'll be going back together with all new gaskets and seals.

I'm a fair mechanic, but haven't done much bottom end work.

is there a good reliable manual or book I should use in this endeavor?

should I just say the hell with it and drop in a $500-1000 junkyard engine with 200,000 miles on it?

will a 617 952 engine out of the 300d fit in place of the 617 951 in the 300SD? keeping all the SD parts except the engine (incl IP and turbo)

summer project. time isn't really important, but money (as always) is.

thanks guys.

karl

[thorsen]

I believe the cylinder lines are pressed into place, meaning you have to take the block to a machine shop and let them do it. Replacing liners is not a shadetree mechanic job.

Your best bet is to find a wrecked car with a good motor.

[glenn1179]

You can resleeve it yourself, but it isn't easy and would have to be taken to a shop to have the sleeves cut to the proper height and bored. The shop better be quality also, because the tolerances are unbelievably tight on these engines. Oh, and yes, you do have to remove the crank resleeve.

If $$ is an issue, take a look at the prices for parts on these engines. The parts alone cost more that a complete domestic engine rebuild.

I bought my 81 300TD in running condition for cheaper than I could rebuild my 240D engine.

If you don't have $$ and/or passion to rebuild the engine, just get another engine or complete car.

Glenn

[nrthrngreaser]

how about the 300d to 300sd engine transplant?

I've located an engine not too far away with 125 k on it for $800. will it interchange? the hollander people list them as two different engines.

Karl

[t walgamuth]

basically interchangable but i am not sure if all years apply. if your car is the same year as the donor engine you are prob in good shape. the best scenario is if you buy a complete car for the donor motor. one that you can start and drive. then change over all parts that differ. this includes (i think) rad, engine, tranny, speedo, and rear end. while at it you may as well change the driveshaft too.

tom w

[nrthrngreaser]

the only thing I want to switch over is the engine, as the rest of the 300 SD is in good shape. why would I want to switch over all that other stuff If I don't have to? I do have an 83 300d but it's little more than junk. esp with the blown head gasket.


Karl

[t walgamuth]

power. and typical of german engineering with more power they fit a higher gear ratio to mitigate the fuel consumption of the more powerful motor. they typically fit a ratio that affords noticably better performance and only slightly less fuel economy.

so if you fit the turbo motor and keep the lower axle ratio you will have a car that has great acceleration and poor (relatively) fuel economy.

when you change the rear end you need to change the speedo to match.

i dont know for sure if the radiators are different or not. i suspect the turbo motor will have a bigger radiator.

you dont have to do all that, but if i were going to do a swap, that is how i would do it. (and have done two of them) when you are done you will have a factory equal job, more or less.

tom w

[sailor15015]

I asked a similar question a while ago because I have an '85 300D that was hit in the rear but has a great motor. I wanted an SD so I asked if everything would switch over. I was told that, if you're only swapping the motor, the only thing you might have to change is the engine support arms, where the motor attaches to the frame. If you're using the engine from the D and the tranny from the SD in the SD body, everything should be fine.

[engatwork]

Just pay close attention to the oil pan you use. I put a '83 300TD engine into a '79 300SD and there were oil pan interence issues. The latter model 300D oil pan has quite a bit more support ribs which tends to hit the 116 lower frame crossmember preventing the engine from sitting down correctly.

[t walgamuth]

and he has an 83 300d which is turbo from factory, so all that other stuff wouldnt apply. just changing out the motor should be fine.

sorry.

i was thinking he had a non turbo car and want to put in a turbo motor.

tom w

[nrthrngreaser]

I do have an 83 300d, turbo'd, however the engine I'm looking at is from an 84 300d going into the 85 300sd which is the 126 chassis not the 116.

basically I was planning on pulling the engine and tranny out of the 126 and parking it next to the engine from the 123, switching any parts that will switch or aren't identical, and putting it back in.

Also putting in new pan and valve cover gaskets, new hoses and belts, new front and rear oil seals, new timing chain and tensioner. probably easiest to do all this while the engine's are out. that and a good cleaning. there's a bit more room under the hood of the 126 as I recall too.

can't be too hard right?

I have read somewhere to dsconnect the torque converter first while in the car.

I'm going to see what parts switch over from my junked 300d, and then give it to a buddy with 2 240's for a parts car.

thanks for your help,

Karl

[dkveuro]

Originally Posted by nrthrngreaser

how about the 300d to 300sd engine transplant?

I've located an engine not too far away with 125 k on it for $800. will it interchange? the hollander people list them as two different engines.

Karl

5 cylinder turbo diesels.....They will fit D or SD...the difference is usually the hydrulic self leveling pump on the front of the cylinder head.
A four speed into automatic or visa versa will require pilot bearing change in end of crankshaft...some later SD's have bell housing holes for crank senors.

.

[t walgamuth]

i dont think sds have the leveling pump. tds do.

tom w