300TD into a 240D engine swap question - PeachParts Mercedes-Benz Forum

mullallyns · #1 01-03-2007, 09:10 AM

Hi there,
I'm new to diesels, new to mercs, but am quite addicted right now. We'll see how long it lasts once I get into this project, however.

I'm about to commit to doing my 1st engine swap. I have a 1980 240D automatic with a blown head gasket, and I can get my hands on a 217,000 km (approx. 140,000 miles) 1982 300TD turbo wagon, which is also automatic (the rear end and body are trashed). I've trolled around the many posts that do a great job of describing 5 banger conversions for a 240D chassis, but all I've seen so far are swaps with a manual transmission conversion as well. I'm wondering about the problems I'll face keeping the automatic transmission on the longer, 5 cyl engine. So, I have two questions at this point.

1. Will it be too long with the big automatic tranny and the 5 cyl engine? Will I have to shorten the front driveshaft too much?

2. And another thought, though I'm 95% sure it won't fit, what about moving the motor mounts forward and leaving the drivetrain the same length, just stick the engine forward instead of backwards?

Thanks. This site is a goldmine for me right now.

DeliveryValve · #2 01-03-2007, 09:42 AM

Quote:

Originally Posted by mullallyns

........
1. Will it be too long with the big automatic tranny and the 5 cyl engine? Will I have to shorten the front driveshaft too much?

2. And another thought, though I'm 95% sure it won't fit, what about moving the motor mounts forward and leaving the drivetrain the same length, just stick the engine forward instead of backwards?

Thanks. This site is a goldmine for me right now.

1. First part of question is no and Second part is you can use the TD's driveshaft if it is not mangled or get another donor one from a 300d turbo. No need for the expense of a custom shaft.

2. Motor mount placement are fixed. But transmission mounts can be place back. There are bolt clips that you can move to different mounting points.

Welcome to this site and keep up updating us with your swap. Many of us like seeing these types of projects!

JimmyL · #3 01-03-2007, 09:51 AM

You have one other monkey wrench thrown into the works. The wagons have a hydraulic rear suspension, and the pump is mounted on the head on the wagons. You will have to come up with some sort of way to seal the opening in the head where the pump is mounted.
No, you cannot move the mounts for the engine. Much easier to find the correct driveshaft.
And of course, as noted in several threads lately, you have to change wiring for an extra glowplug, different exhaust connection and system, tranny mount is moved back, but I believe the holes are there, radiator is different I believe, etc.....
There is more, that is just off the top of my fairly empty head.

And, most important, Welcome!

second, Merc = Mercury

barry123400 · #4 01-03-2007, 10:32 AM

Sorry it turned out to be a blown headgasket. That in itself is not too bad though. The main problem is to make certain all the donar stuff is really good. Usually you can forget the indicated odometer readings around here. Since the cars also sold for a higher price in canada there was more incentive to play with the odometers by car dealers especially plus the notorious failure with use senario. There are exceptions of course but very few of all the maritime examples I have seen. We live in an excellent area to pickup a rusted out hulk with a good drivetrain though compared to our really southern neighbours. Both chassis are identical as far as the power train stuff is concerned and there should be no need to fabricate anything I can think of. The plus is you still retain your more desirable climate system in the 240 as well. Drop by the house again sometime when passing through and you are in the process. You will want to change the rear end over as well for the far more desirable ratio. It would make far too much of a difference to ignore. That could be deffered for awhile. Just make sure you do not send it to the salvage yard after you take the engine transmission and driveshaft.

vstech · #5 01-03-2007, 02:14 PM

you aught to pull the shocks and rear suspension stuff from the TD as well, at least sell it on ebay, if you don't incorporate into your 240D... Enjoy!
John
on second thought, I may need your pump and shocks.... drop me a pm..
John

#6 01-03-2007, 11:36 PM

Quote:

Originally Posted by JimmyL

You have one other monkey wrench thrown into the works. The wagons have a hydraulic rear suspension, and the pump is mounted on the head on the wagons. You will have to come up with some sort of way to seal the opening in the head where the pump is mounted.

The answer for that is a small sheet of 1/4" aluminum and 4 bolts. About $2 worth of parts.

I did it on my engine and it worked fine.

mullallyns · #7 01-04-2007, 03:43 PM

Great! I'm glad to hear that I can get this swap done without too many headaches (i.e., the driveshaft will fit, there are mounting holes to move the coupling back already on the 240d body). I haven't got my hands on the 300TD yet, I'm still haggling for a realistic price. I didn't foresee the leveling pump problem, and thanks to ForcedInduction for providing the great pic of a simple solution.
Now, onto the main snag. I'm 5 hours away from both cars, and can only work on them on the weekends I get back home (I live in Nova Scotia, Canada, but the cars are in my home province). I can't afford to have a mechanic do the swap for me, and I can't justify the week away from work to do it myself, so I'm probably going to get the kids at the local high school do it as a project. I'll pay for parts and the labour is free. I know the instructor pretty well, so I think it will be OK, I'm just bummed I can't realistically do it myself. It would be a great learning experience for me, but I can take some comfort in that some high school kids will learn from the process instead.

Any more advice on what to watch out for would be greatly appreciated, and I'll be sure to post any new snags that come up. I'll probably change the timing chain, replace as many gaskets as I can with the engines out, and get the kids to clean the hell out of everything as they go. I hope that having the parts car handy will give them enough spare parts, as I'm sure there will be some broken nuts and bolts coming out of this project.

vstech - I'll let you know what I have left once this swap is done.

barry - Thanks for all the advice so far. I'll pop by in the spring, hopefully with a 5 cylinder 240d around me.

JimmyL and Forced (or anybody else) - do you have any descriptions of what I have to do to get the glowplug wiring right? Is it more complex than just splitting one of the wires so I have 5 connections instead of 4?

Rmazan - thanks for the confidence boost!

JimmyL · #8 01-04-2007, 04:22 PM

I'm not sure if splicing a wire would be OK, but it would certainly be the easiest. Good question.....

My son's high school autobody shop painted my wagon. Hopefully, your engine swap will go better......

But he put a lot of work in on it, and I get a real feeling of pride when I see one of the runs in the clearcoat.

Oh, and don't get rid of that hydraulic pump for the wagon. I could use a spare.