380SL Diesel Conversion Project - Page 28 - PeachParts Mercedes-Benz Forum

coachgeo · #**406** 05-31-2021, 02:52 PM

Quote:

Originally Posted by ROLLGUY

... the SL has the bolt going through the aluminum piece cast into the rubber of the mount, and goes completely through the mount arm (not just threaded into the aluminum arm).....Rich

my engine mount arms... are not be from an SL but from the W123?. the arm; the mount bolt goes into is threaded,... though guessing you understand that.

Just an FYI.... the mount bolt goes up into the filled one and/or the OEM one ....but it at actually bottoms out at the TOP of the pyramid's tip to snug it into place..... bolt head sits into a counter sunk recess in the metal at the tip of the pyramid. ... but am guessing you know this.

part of what theoretically should help with the filled mounts on preventing torque lift of engine.... is if passenger side is also filled... driver side will have a hard time lifting cause it cant push passenger side down.

coachgeo · #**407** 05-31-2021, 02:56 PM

Quote:

Originally Posted by ROLLGUY

T...., the SL has the bolt going through the aluminum piece cast into the rubber of the mount, and goes completely through the mount arm (not just threaded into the aluminum arm)....

btw.... what does the bolt that goes thru the OEM and filled mount look like? Is there a shoulder on the bolt? Curious how that works if there is no nut underneath as well.

ROLLGUY · #**408** 05-31-2021, 03:15 PM

Quote:

Originally Posted by coachgeo

btw.... what does the bolt that goes thru the OEM and filled mount look like? Is there a shoulder on the bolt? Curious how that works if there is no nut underneath as well.

It's about a 5" long allen head bolt. The poured rubber barely allows a long 10mm allen key to fit through. The 1/2" spacer plate that the mount sits on has about a 3/4" hole in it for the allen key to fit through.

coachgeo · #**409** 06-04-2021, 11:03 PM

Quote:

Originally Posted by coachgeo

so what did you go with again? shore 40? ...

found it; the shore(s) he used to fill motor mounts. This post is a synopsis of his shore trials in this thread. Main thing is his final test was shore 30A.. and that has held up thru at least 2020. sweeeeet.

The post below was the first to show what he used on trial one to fill the motor mounts. Apologize... at first seems I skimmed thru this thread too fast and missed his iterations.

380SL Diesel Conversion Project

In that post he reported trying shore 75D, while in a later post... said 75A ( 380SL Diesel Conversion Project ) ...... Maybe he tried both??

note: A link in another post; in this thread, linked to where he got the 75?. This link seems to point to Shore D was his first trial.... definitely not soft.. it is near as hard as a hard hat.. There is a big difference between A and D but both are hard for motor mounts unless your a drag race machine. . How is shore measured???. A is measured with a more blunt object to develop its rating while D is measured with a sharper point.

as you can see 75D is as hard as a hard hat; 75A still teeth rattle a bit (80A is common for street racers it appears).

later he stated in this thread he was having vibration issues ... appears; he discovered the 75? was too hard and causing this...... (makes since looking at below) he settled with another set of mounts he filled with shore 30A....

A different more recent thread on this topic shows that the OEM MB motor for the OM617's mount is likely shore 40-45A rubber.... thus his final setup at shore 30A as a filler... begins to make ton of sense. Glad to hear this has held up well for nearly a decade.

coachgeo · #**410** 06-05-2021, 06:56 PM

iinexpensive Polyurethane products in a tube? buttttttt.... do your research on temperature they tend to reduce tensile strength etc... they vary by product.

shore 60ish
PL LOCTITE PL Poly Roof and Flashing
3m window weld
3m 560

shore 30ish
Loctite S10 concrete sealant

shore 40ish
3 Polyurethane Sealant 540

shore 45-50
3m, 550, 551
Sikaflex (sika) 1A
Sikaflex 11 FC
Sika Polyurethane Limestone Concrete and Mortar Repair

coachgeo · #**411** 06-05-2021, 09:46 PM

"smooth-on" pour stuff

https://www.smooth-on.com/product-line/pmc/

NOTe..... WET demolds easier..... makes it easier for say letting bolt move if you pour with it in there. ... would likely NOT adhere to the OEM rubber....... which MIGHT be an advantage??? it is also cheaper

TheDon · #**412** 07-26-2021, 09:28 AM

I have decided to diesel my 380SL..

Let it commence!

ROLLGUY · #**413** 07-26-2021, 10:12 AM

That is nice to hear. If you follow this build thread, you will be successful. Everything is covered thoroughly. However, if you have any questions, please ask. And by all means, please post photos and a play-by-play of your progress!

TheDon · #**414** 07-26-2021, 10:42 AM

I plan on it. I saw there is an OM602 in the parts section but I know thats not an easy bolt in. Someone was doing it but they passed away before completing and documenting it fully. Would require custom engine mounts. I think I'll stick with the good ole OM617 Turbo, I miss driving a W123 and I miss driving my E320 Cabriolet with the top down. So why not combine them

I've got to digest this entire thread and pull out the exact parts I need to go aquire before getting a 617 but im going to keep my eyes peeled for one regardless.

I do see you still sell the sanden mount kit and EGR block off plates. I'll becoming to you soon enough

ROLLGUY · #**415** 07-26-2021, 10:56 AM

I am not sure what state you are in, but I have a running '85 OM617 for sale in So. Cal. I also have the 722.4 trans that goes with it, but I think you need the 722.3 trans for your conversion (I believe the stock trans in your SL is a 722.3).

TheDon · #**416** 07-26-2021, 11:42 AM

I'm in FL. I'm poking around in the thread, looks like a lot of work to make the diesel swap happen and in the last 8 years Ive seen the flow of W123, W126, and W116 diesels trickle to almost nothing into my local junk yards. Might be different out west but I might not have an abundance of parts to find for this. I may need to rethink it and stick with the megasquirt conversion.

t walgamuth · #**417** 07-26-2021, 01:55 PM

The megasquirt will be a lot less work. Salability it seems to me about equal.