New W126 OM617 owner needs help identifying Kluges - PeachParts Mercedes-Benz Forum

CanuckWrench · #1 11-27-2011, 09:29 AM

I've got an '81 300SD that I'm getting roadworthy. Alas, the PO bought it from his cancer-stricken friend, then garaged it for 7 years before selling, so I can't ask "what's with this?"

There's a long cable that exits the right side of the IP, near the front. It ends in a three pronged, 1/2" round connector, but isn't connected to anything, just bunched up and baler-wired. My best guess is a temperature sensor for glow plug heating time. Is it? Where should it be plugged into?

The pressure line from the intake manifold to the switchover valve is there, but the line from the ALDA ends at a nearby bracket on the firewall, and there's no line from the bracket to the switchover valve. Was there usually a bracket on this line (so I can assume that the line from the bracket to the switchover inadvertently went missing)? It would be more worrisome if the line normally went directly from the switchover to the ALDA, as then I'd have to assume someone deliberately disconnected it, which makes no sense to me.

There's a sensor on the block between #1 and #2 glowplugs, with no connection on it, and no dangling wire nearby. What is it, and what should it be connected to? There's another similar one between #2 and #3 GP; it's connected.

The driver's door has two door open sensor switches. Sometimes, the warning buzzer sounds when the upper one isn't depressed, even with the key out of the ignition and the lights off. Any ideas?

vstech · #2 11-27-2011, 09:56 AM

a wire on the IP? do you have pictures? it sounds like either an IP or an entire engine from an 85 vehicle was installed in your car.

ROLLGUY · #3 11-27-2011, 10:36 AM

Quote:

Originally Posted by CanuckWrench

There's a long cable that exits the right side of the IP, near the front. It ends in a three pronged, 1/2" round connector, but isn't connected to anything, just bunched up and baler-wired. My best guess is a temperature sensor for glow plug heating time. Is it? Where should it be plugged into?

The pressure line from the intake manifold to the switchover valve is there, but the line from the ALDA ends at a nearby bracket on the firewall, and there's no line from the bracket to the switchover valve. Was there usually a bracket on this line (so I can assume that the line from the bracket to the switchover inadvertently went missing)? It would be more worrisome if the line normally went directly from the switchover to the ALDA, as then I'd have to assume someone deliberately disconnected it, which makes no sense to me.

There's a sensor on the block between #1 and #2 glowplugs, with no connection on it, and no dangling wire nearby. What is it, and what should it be connected to? There's another similar one between #2 and #3 GP; it's connected.

The driver's door has two door open sensor switches. Sometimes, the warning buzzer sounds when the upper one isn't depressed, even with the key out of the ignition and the lights off. Any ideas?

The boost line should be either connected to the overboost protection valve, or just connected to the hose going to the manifold and bypassing the valve altogether. Without it connected (or clogged), you have no boost signal to the ALDA. The front temp sensor on many models is not used, so no worries there. As vstech suggested, the wire coming out of the IP might be from the rack position sensor located on the IP between the block and IP just below the delivery valves. Those IP's were on later cars with CA emissions ('84? & for sure '85). The warning buzzer switch, I have no idea, sorry.....Rich

CanuckWrench · #4 11-27-2011, 12:29 PM

See attached picture for the cable from the IP. Also, note the colour of the dipstick handle. The service manual's oil change section notes that they're "ocher brown" for 617.95 engines from 04/84, and white before that. So I've got an '85+ engine? What changed?

Is the oil filter kit the same pre and post 85? I ordered one for an '81, and got a Mann PF 1055/1n. The filter was the same size, but the large O ring for the canister lid was a bit smaller in diameter and thickness. I figured the old one was just swollen, so I installed the new one. You know how oil change instructions always end with "start the engine and check for leaks"? Well it had a rather generous one, so I swapped in the old seal. Also the crush washer for the oil pan plug was a bit bigger, so I left the old one on there instead.

Thanks.

toomany MBZ · #5 11-27-2011, 01:02 PM

Doesn't appear to be an 85, the ALDA line tells me that, but I'm not familiar with California models.

ROLLGUY · #6 11-27-2011, 04:02 PM

That IP definitely has the rack position sensor. Does your engine have the trap oxidizer? If not, someone could have put in an entire engine, or just a later IP. If I remember correctly, the '81 SD's did NOT have an air cleaner drain tube in the oil pan, but just had the breather hose going into the air intake pipe. The '85 CA emissions engines (or any other with trap ox) did not have an air cleaner drain tube either. Someone could have used a later engine and just used the turbo, manifolds, and air cleaner from the '81 engine.
I needed an engine for my '82 that needed the drain tube, but all I had available at the time was a low mileage wrecked '85. I had to use the upper pan from the blown '82 engine on the '85 block. I also changed out the IP and the trans adapter plate, as the IP had the RPS and the adapter plate had the crank (flywheel) sensor.
That reminds me, does your engine have any evidence of the crank sensor on the trans adapter plate? If so, I would have to say you definitely have an '85 engine.

CanuckWrench · #7 11-27-2011, 04:59 PM

There is a drain tube that runs vertically from the bottom of the air filter housing. I hope the other picture shows where the trap oxidizer would be if I had one. Or would it be further back?

I solved the ALDA boost line mystery. What I thought was a bracket holding it to the firewall was just a hose clamp, so it looks like it just fell off the switchover valve.

Thanks.

toomany MBZ · #8 11-27-2011, 05:17 PM

I don't see a trap ox.

The drain tube is at the bottom of the oil separator, that thing with the tube going to the intake.

ROLLGUY · #9 11-27-2011, 06:00 PM

From the photos, I can clearly see the drain tube from the air cleaner. That would mean that it is probably not the original engine. To find out for sure, look n the trans adapter plate just behind the oil filter stand. If there is a hole there where a sensor was/is, you have a later engine. The sensor lines up with the teeth on the ring gear. If no sensor is evident, probably the IP was the only thing changed.

ROLLGUY · #10 11-27-2011, 06:11 PM

Quote:

Originally Posted by CanuckWrench

Is the oil filter kit the same pre and post 85? I ordered one for an '81, and got a Mann PF 1055/1n. The filter was the same size, but the large O ring for the canister lid was a bit smaller in diameter and thickness. I figured the old one was just swollen, so I installed the new one. You know how oil change instructions always end with "start the engine and check for leaks"? Well it had a rather generous one, so I swapped in the old seal. Also the crush washer for the oil pan plug was a bit bigger, so I left the old one on there instead.

Thanks.

As far as I know, ALL of the 617 turbo engines use the same oil filter from'78-'85. My brother has an '81 NA 617 300CD, and it takes the same filter as well. There should be 2 different copper washers in the kit, plus of course the correct O ring. Maybe someone put the wrong parts bag in the filter box at the factory.

vstech · #11 11-27-2011, 08:00 PM

Quote:

Originally Posted by toomany MBZ

Doesn't appear to be an 85, the ALDA line tells me that, but I'm not familiar with California models.

the alda line is a tough call, can't see the vacuum connector due to the wire in the picture, but it would have been simplicity itself to change the banjo bolt to the one from the 81... however, the fan is metal, so it's not an 84/5 fan for sure, but again, it would have been easy to swap that from the original engine. I'm pretty sure all 126 motors had the air cleaner drain line, it's the 116 turbo's that didn't *(also euro turbo's don't have it...)

only way to know is to look at the trans adapter plate, but it also could have been kept from the original engine... so hard to tell.
look at the front of the head. to the right of the thermostat housing. is there a small steel line connecting the head to the block? if not it's an 84/5 motor.

CanuckWrench · #12 11-27-2011, 08:02 PM

Quote:

To find out for sure, look n the trans adapter plate just behind the oil filter stand.

I hope one of these photos covers the sensor location you're talking about.
Thanks

ROLLGUY · #13 11-27-2011, 08:08 PM

Quote:

Originally Posted by CanuckWrench

I hope one of these photos covers the sensor location you're talking about.
Thanks

It can be seen from the top looking down.

ROLLGUY · #14 11-27-2011, 08:15 PM

Quote:

Originally Posted by vstech

I'm pretty sure all 126 motors had the air cleaner drain line, it's the 116 turbo's that didn't *(also euro turbo's don't have it...)

The two 1981 126 300SD's that friends have, do NOT have the oil separator/air cleaner drain tube in the pan. I had a '80 300SD (116) a year ago that had the oil drain tube and air cleaner just like the '82 & newer 123's. I think that possibly the earlier 116's ('78-'79) might not have had the drain tube, but I can't be sure.

ROLLGUY · #15 11-27-2011, 08:25 PM

Quote:

Originally Posted by vstech

only way to know is to look at the trans adapter plate, but it also could have been kept from the original engine... so hard to tell.

Someone is not likely to change the adapter plate just to not have the sensor hole in it (except me). It is a big job. The engine would need to be mounted somehow in order to remove the flywheel, and then the adapter plate. If they were to go that far, they might as well have changed out the IP too in order to keep it close to original. That is what I did on my '82 300CD. I wanted it all original (within reason) to the '82 using a donor engine from a wrecked '85 with CA emissions.