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Old 05-14-2007, 07:45 PM
t walgamuth's Avatar
Join Date: Apr 2005
Location: Lafayette Indiana
Posts: 32,829
cold compression should be about 220 for reliable starting.

tom w
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual. It still needs upholstery redone...I also have a 427 Cobra replica with an aluminum chassis.
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Old 05-20-2007, 11:06 PM
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Join Date: May 2007
Posts: 10
I removed the injectors in preperation for the compression test and they are nasty and all do not match. one has a hex head and the other four just have two smooth sides with the rest round. I'm not sure if I should have but i took them apart the insides were carboned up and one had two washers in the top instead of one. I think i might buy a new set but am going to do the compression test 1st.
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Old 05-21-2007, 05:28 PM
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Join Date: Jul 2002
Location: S. Texas
Posts: 1,237
From someone who has a 1975 300d I can tell you that chances are that the 75k on the odometer is not correct. The odometer in these cars does not have a 100k mile digit so the car could have 200k or 300k or more on it.

At 75k miles you should have nearly perfect compression. My 115 had 104k when I got it and the compression was nearly 300 psi all round. At that milage virtually nothing in the engine compartment should be worn out. Not unless they never changed the oil.

Take your injectors to a shop and get them popped. They will probably tell you that they are not good in order to sell you new ones, but you could ask to see them tested and ask what is wrong with the spray pattern. If your injectors are miss matched and worn out you can bet that you have a lot more than 75k on the engine.

You may have new GPs but are they all working. I bypassed the GP relay and put a starter button on the dash directly to the GPs. It works like a champ. Hold the button in for a few seconds (I live in S. Texas) and off she goes.

Try the oil in the cylinder trick when you check the compression. If the compression comes up then one, you know your rings are bad, and two, you know that the engine has more than 75k on it.
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Old 08-23-2007, 10:13 PM
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Join Date: May 2007
Posts: 10
new compression #'s

O.K. I did the new compression test and this is what I got.
#1 Dry 130 wet with oil 145
#2 Dry 155 Wet 165
#3 Dry 135 Wet 165
#4 Dry 130 Wet 145
#5 Dry 150 Wet 170
the engine was cold but it was about 80 out.

So now I believe I need some further guidance on how much of a rise with the oil is significant? I had expected to see a big jump if its rings. these Numbers are not that much different. Someone said earlier in the thread if the car sat the cylinder walls could be pitted, would that give me #s in this range?
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Old 08-23-2007, 10:39 PM
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Join Date: May 2007
Posts: 10
one more thought

If the timing chain is stretched and my timing is a bit off
is it feasible to say that the valves are closing a bit late and preventing adequate compression, or am I grasping at straws and have a bad engine?
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Old 08-23-2007, 10:48 PM
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Join Date: Jan 2002
Posts: 18,354
Something is seriously wrong. Seems odd that all the cylinders are in comparable bad condition. I'd expect more variation on an old worn out engine. Can't really account for it myself.
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13
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Old 08-23-2007, 11:06 PM
Cervan's Avatar
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Join Date: Jan 2007
Location: olympia washington
Posts: 1,809
puffs out smoke the intake... thats valve related problems. i suggest you pull the head and check the valves, and then mic the cylinder walls. Unless the chain is stretched to the point where the intake valve is opening on the compression stroke.
Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac?

As long as they would add one additional commandment for you to keep thy religion to thyself.
George Carlin (Wonder where he is now..)

1981 240d (engine donor 1983 240d) recently rebuilt engine hurray! - No more.. fought a tree and the tree won.

pearl black 1983 240d 4speed (Converted!@$$%) atleast the tranny was rebuilt.
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Old 08-23-2007, 11:19 PM
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Join Date: May 2007
Location: Jacksonville, Florida
Posts: 102
Do you find any cans, full or empty, of ether within several miles of the car. Have seen many a diesel ruined by juicing them. Have seen vehilces with a stash of empties in the trunk and every piston ring broke.

Just more detective work.
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Old 08-24-2007, 01:35 PM
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Join Date: Nov 2005
Posts: 152
Just my 2 worth....

I think the compression is too low for the engine to be in any kind of runable condition...

It won't cost anything to disassemble the engine...other than your time. I think you'll find some worn cyclinder liners that will be visible by the large ridge at the top of the cylinders.

Unless the body on this car is rust etc...I say "doomed". The interiors last forever on these models so it's tough to tell how many miles are on it...Besides, these models have little or no collector interest...

I rebuilt an old 1977 240D because of a worn-out really wasn't worth it as there are so many great examples still running out there...It didn't seem like a lot of money for the pistons, liners, and gasket set, but there are a lot of parts that once the engine is apart, you have to make decisions on what to replace and it seems like almost everything.

Just my 2 worth...

The Tenor Man
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Old 08-24-2007, 11:34 PM
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Join Date: May 2007
Posts: 10
I am going to go ahead and have a look at the timing

I think from here I will check the timing chain. I also will check the valves.
I guess its true that it doesnt cost anything to open it up and have a look but I have never been into one that far. About a 150 miles from me I found a farmer with the same exact car except two years newer. He got it from a used car dealership that closed up shop. It is complete but is missing the I.P. He hinted at 100.00 for it, but if I drag in another Non-running car I will probably have to sleep in the back seat. I am about an inch from calling it quits with this one and parting it out. If anybody has a trade that would work I might consider that too.
For now im keeping my fingers crossed on the timing.
Also I have never seen any ether near the car.
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Old 08-24-2007, 11:37 PM
BlackSheep5's Avatar
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Join Date: Oct 2006
Location: 85616, AZ
Posts: 230
PM me the VIN and I will tell you if the 78,000 miles is correct or not.
06 VW Jetta TDI
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