380SL Diesel Conversion Project - Page 4 - PeachParts Mercedes-Benz Forum

vstech · #46 12-06-2011, 10:43 PM

Quote:

Originally Posted by whunter

all pictures to this thread

I edited the thread and substituted locations so all the pics are on our server.

mach4 · #47 12-06-2011, 10:53 PM

Quote:

Originally Posted by whunter

Please post the supplier data.
Contact information and/or URL.
Polyurethane stock number.

I sourced the urethane locally from Aeromarine Products - AeroMarine Products - Epoxy Resin, Urethane Foam, Silicone Mold Making Rubber although most of their business is mail order and eBay. I used their jet black casting resin because the hardness was what I needed and it sets up quickly.

I've used Aeromarine epoxy for other projects so I was comfortable with the quality and support.

mach4 · #48 12-07-2011, 09:35 PM

Spent some time today working on the remote oil filter mounting and the motor mount spacers.

I didn't want to weld the oil filter bracket to the fender well, so I fabricated what is essentially captive nuts to bolt the bracket to the fender well. I welded two nuts to a sheet metal backing then snaked it inside the fender through an existing hole and pop riveted it...something like this. (The fishing line is just to be able to retrieve it if I dropped it before it was riveted)

With the bracket bolted in place I fabricated a piece that is welded to that piece such that I can bolt the mounting plate from the remote oil filter to it. This gives me the ability to remove the oil filter housing intact without removing the fender bracket. Still have to drill and tap for the oil lines and get new mounting bolts - if I did this again I would tap the bracket and be able to use the original bolts... oh well. The lines on this end will be 90 degree AN fittings.

If you look closely you can just see one of the oil cooler lines to the right of the filter. These are actually cut down cooler lines from the radiator end which I'll braze on -10AN fittings for high pressure stainless braid hose. Instead of running along the engine I'll run along the fender well to the radiator.

Here's the painted bracket with the oil filter housing removed. The bulk of the weight is carried by the two bolts on the top, and the two 1/4" sheet metal screws at the bottom provide additional stability.

Finally, I got the motor mount spacers cut and drilled and painted. And while I was at it, I opened up the center hole in the urethane filled motor mounts to 3/4" to facilitate access for the main engine mount to engine arm bolt.

Here is the aluminum remote oil filter plate on the engine side with a 1/4NPT-10AN fitting mocked up. It's very tight on the bottom, so I might need to forgo the third line for the bypass filter return.

The subframe mods and the transmission yoke swap are pretty much it to put the subframe and engine back in and start hooking up all the hoses, wires, lines and linkages though I'll probably wait to get the radiator mounted to take advantage of access through the engine bay.

Squiggle Dog · #49 12-07-2011, 09:58 PM

I'm really liking this project!

t walgamuth · #50 12-07-2011, 11:03 PM

Your approach is methodical and logical. Good work!

mach4 · #51 12-09-2011, 02:28 AM

While I was getting ready to modify the front subframe I noticed something that just didn't seem right. The motor mounts didn't appear to be lined up. I decided to find out if it was for real or an optical illusion.

The yardstick is exactly aligned to the edge of the spring towers (red arrows). The spring towers must be symmetrical both with respect to the A arms and side to side. The motor mount centers are clearly not symmetrical left to right as I would have expected and pretty much assumed (yellow arrows).

This anomaly also showed itself when I removed the 380SL engine and mounted the 617 engine on my roll-around engine stand as the mounts were not centered on the uprights.

The subframe image also shows pretty graphically the area in the right front crossmember that needs to be clearanced for the pan.

Now it is pretty much agreed that the German engineers did stuff for a purpose, but I cannot think of any reason to have asymmetrical motor mounts...

t walgamuth · #52 12-09-2011, 07:02 AM

I would assume it is to counteract torque or vibration tendencies of the motors. The question is are the arms offset on your diesel too?

mach4 · #53 12-09-2011, 01:16 PM

Quote:

Originally Posted by t walgamuth

The question is are the arms offset on your diesel too?

Nothing is symmetrical. The mounting of the arms to the engine are in different relative positions on the side of the block and the bolt pattern and width are different as well. The arms are different with one being straight and the other arcing backwards. And of course the engine mounts in the subframe are not symmetrical either.

The only point is that for anyone doing a swap with this engine should be aware of the situation and measure and fabricate each side separately as required.

t walgamuth · #54 12-09-2011, 01:57 PM

Quote:

Originally Posted by mach4

While I was getting ready to modify the front subframe I noticed something that just didn't seem right. The motor mounts didn't appear to be lined up. I decided to find out if it was for real or an optical illusion.

The yardstick is exactly aligned to the edge of the spring towers (red arrows). The spring towers must be symmetrical both with respect to the A arms and side to side. The motor mount centers are clearly not symmetrical left to right as I would have expected and pretty much assumed (yellow arrows).

This anomaly also showed itself when I removed the 380SL engine and mounted the 617 engine on my roll-around engine stand as the mounts were not centered on the uprights.

The subframe image also shows pretty graphically the area in the right front crossmember that needs to be clearanced for the pan.

Now it is pretty much agreed that the German engineers did stuff for a purpose, but I cannot think of any reason to have asymmetrical motor mounts...

Will the 617 front pan fit between the crossmembers?

mach4 · #55 12-09-2011, 02:16 PM

Quote:

Originally Posted by t walgamuth

Will the 617 front pan fit between the crossmembers?

Yes. I'm going to clearance the right side of the front crossmember a bit and then box it for additional strength.

mach4 · #56 12-10-2011, 12:45 AM

Got the front crossmember clearanced and boxed today. Pictures turned out horrible so I'll see if I can get some tomorrow when the light is better.

Also back tracked on the remote oil filter and redid the mounting plate on the filter housing. I did it out of aluminum this time and drilled and tapped the mounting holes so I can use the original bolts. Got it mounted up and determined that I'll need to drill one more mounting hole to triangulate where the two brackets join. It seems to be pretty secure, so I don't think I'll need to add a support the top of the canister.

The remote mounting means that I'll have to re-do the turbo supply line as well as the cooler lines. I plan to use the stock hard line from the turbo to the back of the engine and then braze a -8AN fitting to that line as well as a stub line from the banjo fitting on the oil filter housing and use high pressure aircraft quality stainless braided hose to connect the two.

Started to set up to pour the urethane to support the subframe mounts, but ran out of time.

Druk · #57 12-10-2011, 03:48 AM

Quote:

Originally Posted by mach4

Today was focused on getting the subframe spacers done.

I'm a member of the local EAA (Experimental Aircraft Association) chapter and they have a couple of lathes at the hangar that are available to members, so I was able to go down there and log some lathe time.

They will never win a machinist award, but they are functional. I made them a little more than 1/2" but I can just turn the shoulder a bit if I end up with better hood clearance than I'm anticipating.

Are you still having to go down this spacer road? I would be concerned that by spacing the subframe away from the body you're going to alter the angles the steering box and idler arms make with the tierods to the wheels. Have you done a trial lock -to -lock with the steering? I ask because I'm in the throes of a similar conversion and at full lock the inner balljoints are very close to the sump edge both sides. By dropping the engine relative to the center tierod that clearance may be gone. Being in the UK I have a different problem. Whereas your steering box fouls the oil filter, on a right-hand-drive car it's the exhaust downpipe that has no place to go; the steering box being on the opposite side.

mach4 · #58 12-10-2011, 04:33 AM

Quote:

Originally Posted by Druk

Have you done a trial lock-to-lock with the steering? I ask because I'm in the throes of a similar conversion and at full lock the inner balljoints are very close to the sump edge both sides.

Hmmm... No I haven't, but I should be able to get the subframe back in the car this weekend and check. I just need to get the urethane poured in the subframe mounts and it will be ready.

Which sump are you using? And which engine?

Remoting the oil filter is a relatively simple task compared to "remoting" the down tube. What is your plan?

Druk · #59 12-10-2011, 05:18 AM

I'm using the 606 turbo engine which has an ally sump. The engine is inclined naturally so doesn't have the same height issues. The down tube is being routed in front of the main subframe Xmember which is where the original went in any case. My car was a Euro 280SL in it's past life

. That will require the turbo to be re-mounted back-to-front with the Xhaust outlet facing the rad but that is a minor job.
BTW, I'm using the same type rubber feet as you but uprating to the petrol 500 V8 version. I did a deflection test on the original 280 mounts and compared that to the hydraulic ones that came from the W210 donor car. The difference was 1.5mm more for the 280 ones. Almost insignificant but I'm going to the V8 ones which have a harder compound (I'm reliably informed). Interesting that you filled yours with urethane. I'm now looking at sourcing some of the same in the UK. My original ally engine feet are way out so will be fabricating new ones to suit the mounts using 10mm steel.

There's a member of the UK Mercedes-Owners-Club who has the same engine conversion as you in an R107. Unfortunately, he's not on the Club forum so I can't ask him questions.

mach4 · #60 12-10-2011, 12:34 PM

Quote:

Originally Posted by Druk

I'm using the 606 turbo engine which has an ally sump... That will require the turbo to be re-mounted back-to-front with the Xhaust outlet facing the rad but that is a minor job.
BTW, I'm using the same type rubber feet as you but uprating to the petrol 500 V8 version... Interesting that you filled yours with urethane.
There's a member of the UK Mercedes-Owners-Club who has the same engine conversion as you in an R107. Unfortunately, he's not on the Club forum so I can't ask him questions.

Sounds like a great project. I look forward to comparing notes. Too bad the guy in the UK club isn't on the forum, it would be nice to have the benefit of his experience. One of my goals with the build thread is to document my thinking and solutions for those that might want to tackle a similar project.

Your downtube solution is elegant.

Did you have to clearance the subframe at all with that engine?

Isn't that engine electronically controlled? And if so have you figured out that aspect? I made the decision to stay with a completely mechanical engine to avoid any of those hassles.