Can -not keep '76 300D running - Page 2 - PeachParts Mercedes-Benz Forum

thayer · #16 12-11-2008, 10:47 AM

tell me you've checked the fuel filter

jross · #17 12-11-2008, 01:07 PM

Quote:

Originally Posted by thayer

tell me you've checked the fuel filter

Sorry to disappoint.. havn't checked that yet. I'll do that when I go check on the car in a few hours. Good call.

kerry · #18 12-11-2008, 01:29 PM

Quote:

Originally Posted by jross

The overheating was either an obstruction in the cooling system, or the water pump failed. The engine got hot enough to melt the Viton lines while the radiator was cool enough to touch. It is entirely possible I blew the HG, which I'm hoping wasn't the case. I'd like to try and get the car running well enough to limp home in stages (it's on the road about 25 miles away) before digging into repairs like the water pump - or, heavens forefend, the headgasket.

By the way, before I go disconnecting the fuel lines, where is the primer pump on these cars? I can't find anything that looks like a primer, and that was the first thing I went hunting for. I have a spare primer of the old IP from my '83 Frankenbenz (had to fix that a few months back) that I can plumb in, but it would be handy if there's one there already for when I switch back to car's fuel tank.

Primer pump is on the side of the IP, downstream from the primary fuel filter. They have a reputation for leaking and there is an updated pump available. OE pump has a round white plastic handle that must be unscrewed. Updated pump has a black spring loaded push button that does not need to be unscrewed.

Palangi · #19 12-11-2008, 07:07 PM

Quote:

Originally Posted by kerry

Primer pump is on the side of the IP, downstream from the primary fuel filter. They have a reputation for leaking and there is an updated pump available. OE pump has a round white plastic handle that must be unscrewed. Updated pump has a black spring loaded push button that does not need to be unscrewed.

76 300D on 115 chassis is an odd beast, not like a 123, and not like a 115 240D..

Primer pump is the round disc looking thing on the side of the main fuel filter. No unscrewing required, just push on the disc.

kerry · #20 12-11-2008, 07:08 PM

Quote:

Originally Posted by Palangi

76 300D on 115 chassis is an odd beast, not like a 123, and not like a 115 240D..

Primer pump is the round disc looking thing on the side of the main fuel filter. No unscrewing required, just push on the disc.

Ooops, sorry.

jross · #21 12-11-2008, 09:40 PM

Quote:

Originally Posted by Palangi

76 300D on 115 chassis is an odd beast, not like a 123, and not like a 115 240D..

Primer pump is the round disc looking thing on the side of the main fuel filter. No unscrewing required, just push on the disc.

No wonder I couldn't find the damn thing.. I was hunting down by the IP!

Many thanks

Palangi · #22 12-11-2008, 09:47 PM

My 86 Isuzu diesel has that type of primer pump. It started sucking air, so I had to replace it. I never heard of one leaking on an MB diesel, but keep in mind that the possibility exists.

Also, the main filter on that car has a drain plug, but make sure the primer works before you drain it.

rummur · #23 12-14-2008, 03:40 AM

How do you check the injection pump oil if your car has the OEL cap?

katja · #24 12-14-2008, 10:59 PM

I don't know how one can see the oil in the injection pump...but you remove a small "check" screw toward the bottom of the pump, put a container under it, and then you add oil at the red OEL cap until pure oil drains out, then stop. Once it stops draining out of the bottom screw I believe you are at the correct level.