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-   -   1980 300D into 1982 240D AND I NEED HELP! (

oilslick 11-28-2003 09:11 PM

1980 300D into 1982 240D AND I NEED HELP!
Donor and recipient cars are automatics. The 300D driveshaft has a bad center bearing on the driveshaft. The driveshaft has also been "tampered" with without taking care to keep everything lined-up. Not my doing. Would I be better off to have my 240D driveshaft shortened (it's in great shape) and balanced or do the repair work to the 300D driveshaft?

Is it absolutely necessary that I change the differential from the 300D to the 240D?

Is there anyone on this forum that can tell me if the 300D engine IS in fact a 1980 by these numbers, (617 912 12 106 286), stamped on the block above the oil filter housing?

Can I use the 240D oil cooler with this 300D engine?

Am I correct in assuming that the trans lines will need to be swapped from the 300D to the 240D? A/C lines?


oilslick 11-29-2003 09:24 AM

Hello? Anybody out there?
Guess I am on my own.

Oh well:(


Ken300D 11-29-2003 11:16 AM

It's not as common a task as the routine maintenance things we talk about mostly.

Only thing I can remotely help you with is the driveshaft. From the manufacturer there are alignment markings on the two sections of the driveshaft. On the short section it is one short mark on one of the six sides where you fit a wrench (near the junction with the other section). On the long section it is two marks shaped like a portion of a V and I think they are on the yoke of the universal joint.

If I feel energetic later this weekend I'll get you a picture with these parts highlighted.

For my part, I would try replacing the center bearing and carrier mount on the 300D driveshaft - and get it put back together in alignment.

Its going to be pretty tough to shorten the 240D driveshaft and keep it strong and in balance.


oilslick 11-29-2003 02:43 PM

Thanks ken!
I really appreciate the information. I also look forward to the picture.


oldfrt46 11-29-2003 10:51 PM

Hi Oilslick! Where in SC are you? I'm in Greenville. I swapped a 78 300D 5 cyl into a 78 240 without changing the differential. One of the forum members said the gear was probably a little lower in the 240 and would help on take-off. Seems fine to me. My situation was a little different than yours. I also swapped the auto from the 300 into the previously 4 spd 240 which was a little more trouble. I pulled the 5 cyl with the AT still attached and dropped them into the 240. Then just moved the entire driveshaft over to the 240. Wiring the AT to work in the 4 spd 240 was tough but the forum members were a tremendous help.:D

oilslick 11-30-2003 01:28 AM

Where in G'ville?
Just moved from there about 2 years ago- Berea!

I live in Seneca now!


psfred 11-30-2003 06:28 PM


Take the rad from the 300, it's bigger. Re-align the driveshaft if that is possible, and replace the center bearing and carrier. Or get another driveshaft, it's far cheaper to get a used on it good shape than mess about with shortening and balancing the one from the 240.

You will need to move the tranny crossmember back, too.

I'd swap the rear end, too, otherwise you will be burning too much fuel. Change the speedos over, and swap the gear on the end of the speedo drive to keep the correct speedometer reading.


oilslick 12-01-2003 08:12 AM

Let me ask you guys this question.
Since the driveshaft from the 240D is in great shape and the one from the 300D is not (bad center bearing and bushing) could I not just swap the center bearing and bushing from the 240 to the 300 driveshaft? Possible?


Are the drive axles from the 300 the same as the 240? My 240 needed one axle so I thought I might swap out that whole assembly since I am doing a major task now. BTW, thanks for your info.


Ken300D 12-01-2003 10:52 PM

1 Attachment(s)
I believe the center bearing and support are the same between the 240D and 300D, so you could swap them. The difficulty I have always had is in getting the bearing/support assembly off in one piece. My puller tends to rip off the outer shell of the support first, then I have to go back and get a grip on the bearing itself. You'd have to have a way to grip the bearing directly, even with the larger support surrounding it.

Here's a fuzzy picture of the alignment marks. I haven't got the hang of close-up focusing yet: The two marks on the U-joint yoke are easy to see. The one mark on the wrench flat on the short driveshaft section is harder to see.


oilslick 12-01-2003 11:17 PM

Many, many thanks!
I really appreciate that! I will be working on it in the morning. I will be rolling in a new timing chain as well. Any advice?


psfred 12-02-2003 06:49 PM

If you are working alone, make sure to secure both ends of the chain while chaninge clamps, wires, whatever.

I was lucky when I dropped the slack end, it piled up on top of the crank and I could fish it back up. You may not be!

Also, if you always keep the chain on the sproket, it's easier to get the ends to match -- takes quite a bit of pull to get the new (and oily!) chain up to correct position if it wasn't there.

Ditto for the pulled side, too -- you can goof up the injeciton timing if the chain slips.


engatwork 12-02-2003 07:07 PM

Here is the way I did it. Have a bunch of tie wraps handy and take your time.

The two tie wraps/section as shown is overkill for rolling it in. In this shot I had the new chain in and the old one out and was in the process of getting ready to remove the center tie wrap and install the link.

Fisherman 12-02-2003 07:29 PM

Master link
Someone once mentioned that the master link for a gasser chain fits loose enough to use as a temporary link while rolling in the new chain. Then you can remove it easily and use the peened link to finish teh job.

engatwork 12-02-2003 07:40 PM

To roll it in I just use a master link with the "locking" clip. After getting the new one in place I remove that temporary clip and install the permanent one that gets "peened" or fastened in place with the chain crimping tool.

Fisherman 12-02-2003 07:50 PM

Exactly, I think that was the reference to the gasser version of the link.

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