r129 diesel conversion - Page 6 - PeachParts Mercedes-Benz Forum

bkc · #76 07-19-2017, 10:56 PM

More recent updates... (sorry for the fuzziness of the pics, they didn't look bad on the camera's screen)

Couldn't find the original ground strap (nor the one from the wrecked w124, nor the w124 one I pulled from a junkyard - ground strap gnomes somewhere?), so we put on one which I was wary of - it seemed too wimpy.

Filled all the fluids. Just some basic conventional oil for now, as "break in" oil. (Will change out for the synthetic after the first few hundred miles.) Used water in the cooling system for now, in case we have to drain it again. Will do a full coolant exchange with the machine once things are good. Topped off p/s fluid from initial refill a few months ago (after making the new lines). Filled ATF (will do a full fluid exchange later, once the new machine comes in, followed by a filter change after).

Sorted the remaining rat's nest of wires in the electronics bay, capping off unused (for now) wires and completing the OVP circuits.

Using a Spectre conical air filter for now. Not sure I trust it to not let through too much grit, but couldn't find anything else that fits without major modifications and relocations, yet. It is directly on the turbo intake via a step-down coupler. Blowby hose is just hanging there for now. This motor didn't have much/any blowby when it last ran, so hopefully won't make a mess.

Put five gallons into the tank. Added a manual primer pump/bulb (marine use) to get the fuel all the way through the system, other than the hard lines. Was amazingly satisfying to see the fuel flow through the (new) clear lines to/from the main filter. It was the first time it began to feel "alive" to me!

Found a few bolts and connections that were loose during final check over. Tightened the screen in the tank (slight leak). Installed a bunch of those circular clips to hold wires and hoses in place, made sure all the injector line brackets and clips were installed properly. (Never understood why I never see a car that has those remaining. Often with elaborate alternative attempts to protect the lines. The clips are cheap and easily available from the dealership, even from some third-party vendors.)

Installed the battery. Was very relieved when nothing arced or blew up.

Tested preglow system. Turned key to Run, Check Engine light lit up, then went out after reasonable time. (I had wired the preglow relay to that light, since irrelevant for this engine, and is in the expected far right location -- couldn't find the proper insert [140-584-07-17, NLA], may eventually scrape off the lettering and paint a preglow symbol). Guy checking preglow output confirmed that the glowplugs were being sent power appropriately. Glad I managed to get all that properly wired from the get go!

Halted startup after smoke from front left fender. Upon investigation, found that I had grounded a live wire (tan or dirty white with red stripe). Duh. Well, if that is the worst I miswired over a three year period, I'm doing well. Replaced #9 fuse (after capping off that power feed wire).

Found that the neutral safety switch wiring was wired up properly, as I kept wondering why I couldn't get the engine to start. Until I realized I still had it in Neutral from all the times we've pushed the car around the shop. Once it was in Park, was able to get engine cranking and start to bleed the injector hard lines.

Halted again after hearing weird metal swishing sound. Upon investigation, found that none of the six torque converter bolts were installed! I guess we should have been suspicious when there were only two bell housing bolts installed. Looks like the guy at the other shop (who did the driveline spacers) test-fit the motor and tranny together, then forgot it was only test-fit and installed it?

While underneath checking things out, found that I had been right to be concerned about the ground strap we put on. It was melting (at least it wasn't smoke from the starter overheating).

Ordered up the TC bolts and two ground straps from the dealership (none of our vendors had them). As is typical, after ordering the ground straps, I found the original one, suddenly, right in the box of parts where it should have been all along. Definitely gremlins or brownies or something!

Engine sounded and felt healthy, so far, except for torque converter issue.

While we waited for the dealership parts to come in, I replaced the broken swaybar link (probably from when the wife sideswiped a curb less than 24 hours after installing new wheels and tires, actually cracking both wheels on that side...). Replaced the other side as well while I was at it, since they are only $6 each and easy (and plastic). Only concern there is that I may need to recalibrate the little arm sensors on the underside of the control arms which sense an impending rollover and trigger the rollbar. Not sure how sensitive they are.

Also while waiting, finally reglued the hood pad. Previous owner had proudly told me they put the new one on themselves - unfortunately, they used a crappy glue, only sprayed it on sparingly, and only on one side. Needless to say, it fell off within weeks of acquiring the car.

Cleaned and installed the various exhaust shields. Installed the downpipe my exhaust tech built (complete with flex tube) so at least the exhaust will go down at the floor and not into the engine compartment. Need to get the car mobile enough to get it onto the rack at his home (three houses away) so he can properly fit a new exhaust to the car (using r129 resonator/muffler).

Looking forward to getting this thing running! At least the motor isn't seized or any other major issues, so far. Was concerned, given how long this project has taken.

bkc · #77 07-22-2017, 04:31 PM

OM602 engine installed in r129 engine bay, ready to run:

The current rat's nest of the electronics bay:

The questionable but logistically simple Spectre air filter and setup:

Manual primer pump (will probably swap it to be before the inline filter later, to make securing both much better):

Melting ground strap:

bkc · #78 07-22-2017, 04:36 PM

Got the TC bolts and ground straps in from the dealer. Bolts are good, but the ground straps are just as wimpy as the one we had thrown on there that melted! I gave them the part number from the EPC based on the VIN. I think their "updated" part is not very useful. Will be returning those.

Installed the TC bolts (37 lb-ft).

Started up the engine, glowed and cranked nicely.

Began priming the injector hard lines, me inside, two guys in front. Got #1-#4 primed. Then the motor began to runaway. Sounded like a jet engine taking off!

I was inside the car, so couldn't quickly get out (long doors, lift support). Was shouting to the guys to hit the STOP lever, but apparently they couldn't remember where it was (I'm the only Mercedes diesel guy here). I guess when I showed it to them, it was just academic knowledge, not crisis information... One of them panicked and went to undo the battery (in the trunk), thinking about gas engines.

Finally was able to get out of the car and to the lever and shut it down. (Fortunately was just a fuel issue, not oil mist or such, since the lever instantly stopped it.) It definitely got some pretty high revs going, and didn't seem to want to stop climbing.

The guys at the BMW shop next door had been trying to decide whether to run over to try to help or to run away.

Definitely got a bit warm. Heard the cooling metal pinging for a while. Found it had spattered some oil out the right hand side, under the exhaust. Probably the headgasket (it was already starting to leak elsewhere, was on the list of things to address once up and running).

Next day, hooked up the vacuum line to the shutoff lever into the cabin with a hand pump attached (and tested it dropped lever). Checked vacuum line routing to IP, seems to be correct. Installed EDS ECU, in case it needs some circuit completed. Tried starting it again. Almost instantly began to runaway again. Shut it down.

At least it still sounded healthy. No oil spewed this time.

Have now run the vacuum cutoff line into the driver compartment (was originally working on a solenoid for key off, but after runaway, ran this for now).

(Might retrofit the overboost circuit I pulled from a 1987 190D 2.5 Turbo. My 1990 300D 2.5 has it, so I have a live model as well as the diagrams for hooking it up -- it was eliminated for the 1993 MY.)

Any thoughts on what might make the IP go crazy? The motor originally was driven right into my home garage before being pulled, so has barely spent any time outside without being installed. Something stuck in the governor? Am I missing something obvious? Will definitely be checking over those vacuum lines again.

97 SL320 · #79 07-22-2017, 06:54 PM

Is the throttle linkage pulling in the proper direction?

The injection pump rack can stick after sitting for an extended period. I don't know this pump specifically but there has to be a way to view / cycle the rack by taking a few parts off.

The ground strap should run from the transmission to body. You could double them up for higher capacity.

ROLLGUY · #80 07-22-2017, 08:46 PM

Quote:

Originally Posted by 97 SL320

Is the throttle linkage pulling in the proper direction?

The injection pump rack can stick after sitting for an extended period. I don't know this pump specifically but there has to be a way to view / cycle the rack by taking a few parts off.

The ground strap should run from the transmission to body. You could double them up for higher capacity.

That was my first thought as well. Also, if the cruise control servo is hooked up, it may be causing the problem. They have a habit of causing accelerator linkages to stick WOT.

ROLLGUY · #81 07-22-2017, 08:52 PM

Another thought (only a possibility, but easily tested)- Next time you try to start it, remove the crossover pipe. If lube oil (a lot of it) is getting past the turbo seals, that will cause runaway. With the tube removed, oil will spray on the hood pad, and not in the intake. If that solves the runaway problem, you know what to do......Rich

vstech · #82 07-23-2017, 11:39 AM

on the runaway...

look at the throttle linkage. look for ANYTHING that could be restricting motion.

it appears your transmission dipstick is pressing against the transmission side of the linkage... that would do it...

Desert Panther · #83 07-23-2017, 11:01 PM

Quote:

Originally Posted by bkc

As is typical, after ordering the ground straps, I found the original one, suddenly, right in the box of parts where it should have been all along. Definitely gremlins or brownies or something!

Man, I cannot tell you how many times this has happened to me personally! It's ridiculous!

Good to know I'm not the only one this happens to!

I'm loving your project & watching its progress. Keep up the good work

jay_bob · #84 07-24-2017, 09:16 AM

Detach the linkage from the IP and repeat to see if something is forcing the speed above idle. If you are able to stop it with the stop lever, it's not oil ingestion, it's the IP getting commanded to deliver more fuel.

Did you replace the stop actuator? It's easy to get the linkage inserted wrong, and that can cause the rack to jam to full fuel position.

Your melting ground strap concerns me, you have current going somewhere it should not be.

bkc · #85 07-25-2017, 01:49 AM

Here's a picture of the original groundstrap (installed) with the one that partially melted held up next to it. Notice the huge difference in sizing.

(Oh, and tranny dipstick is extremely close to tranny linkage bracket, but it is actually clear and has the bracket separating it from any possible interference.)

As for the runaway, we finally found that the white fitting that guides it through the firewall (up behind the expansion valve and such) had come loose and was keeping the throttle cable at 3/4 WOT at its lowest. Both embarrassed and relieved it was something so basic and simple.

So, now it is running! Still fairly rough, but it *has* been sitting for 5 years. May also go and bleed the injector lines a second time, still feels like there might be air in there.

However, new problem.

When I went to shift into gear, absolutely nothing happened.

We raised it on the lift and checked that the linkage is moving the lever on the tranny body, and it is making distinct thunks into each position. Fluid level is correct/slightly high per dipstick (with engine running). Honestly, level should be a bit low, since it had years to drain out all but TC. Suspicious...

Car seems to know what gear it is in (and matches with shifter/lever positions). Rollover alarm sounds when in Drive (on the lift, and therefore with wheels off the ground). NSS works as expected. Just absolutely no feel or sound of anything happening inside the tranny.

Will try checking tomorrow whether there is pressure in the cooler lines. Our current thinking is that the tranny pump is dead or extremely weak. Or possibly a problem inside the TC. Wondering whether the pump could have been badly damaged by the runaway? It was in Park, but the pump would still have been connected to the motor.

Another oddity as we were checking the tranny issue is that, when in Park, the rear wheels can be turned by hand. The driveshaft doesn't move (it is locked down properly by the tranny), but the wheels can be spun freely (turning in opposite directions, of course). I don't think this diff has any sort of electronic release or such???

When the tranny is in Drive (tested with engine off), the wheels are connected to the driveshaft motion (limited in test, but definitely linked).. Shaft and wheels are linked and spin freely by hand when in Neutral (as expected). Not linked when in Park

Will drop the pan tomorrow and see whether anything is obvious from inside.

bkc · #86 07-25-2017, 03:50 PM

Sigh. Opened up the tranny. Strawberry milkshake. Should have dropped the pan and checked for water from when the previous guy worked on it (plus sitting around) before using it. Although if it was condensation, then, who knows, it may have been toast from pretty early on.

TRC quotes nearly $3000 to rebuild it (and that is shop wholesale pricing). Checking with Sound German Auto in Bellevue for a quote on maybe putting a 722.6 in it instead. As I recall he (whipplem104) previously had a w123 with om602 and 722.6 with his standalone controller. Sigh. There's goes another big chunk of cash.

ROLLGUY · #87 07-25-2017, 04:11 PM

It would not hurt to do a full drain and flush. It may bring it back to life. If you use compressed air through one of the cooler fittings (banjo bolt removed with rubber tip blow gun in the hole), it will get most of the old fluid out. The converter has a drain as well. Start with fresh cheap fluid, and it may start to work. If it does, drive it a little and drain and fill again. Be sure to remove the filter before using the compressed air. I wouldn't be surprised if that fixes it........Rich

dieselbenz1 · #88 07-25-2017, 04:23 PM

Check on ebay I noticed several times Sun Valley sells reconditioned ones for around $1800 complete with warranty.

bkc · #89 07-30-2017, 01:39 AM

Quote:

Originally Posted by ROLLGUY

It would not hurt to do a full drain and flush. It may bring it back to life. If you use compressed air through one of the cooler fittings (banjo bolt removed with rubber tip blow gun in the hole), it will get most of the old fluid out. The converter has a drain as well. Start with fresh cheap fluid, and it may start to work. If it does, drive it a little and drain and fill again. Be sure to remove the filter before using the compressed air. I wouldn't be surprised if that fixes it........Rich

Hey Rich. Thanks for the suggestion but, from everything I've been taught about trannies, the water will have delaminated all the clutches and probably will have damaged the seals. There is also zero pressure in the cooler lines, so the pump is dead.

We actually have a tranny fluid exchanger (Mahle ATX-3) here, but we think it is too far gone for even that to work. Plus, with the internal pump not working, can't really exchange fluid anyway.

Thought I had a line on a used C-class with the right tranny and a dying motor (so I could actually test whether the tranny in it is still good), but it turned out to have the m271 motor, which apparently has a different bellhousing than I need.

-Bruce

97 SL320 · #90 07-30-2017, 10:22 AM

Got any pics of the oil water mix? It might not be a bad as first thought. Yes, water will delaminate paper clutches.

Given the past person that worked on the car ( mounts and such ) , I'm thinking the lugs on the converter / pump are broken off.

Was this trans working prior to the new install?