Replace 602 with 603 in 92 124 - Page 4 - PeachParts Mercedes-Benz Forum

Diseasel300 · #46 01-22-2018, 02:28 PM

Those are pretty awful compression numbers.....how many miles did the car have on it?

dieselbenz1 · #47 01-22-2018, 03:31 PM

263000 km hmm I thought they were decent for a cold engine

Diseasel300 · #48 01-22-2018, 03:50 PM

The enormous difference between dry and wet compression is a pause for concern. Stone cold compression on my car is 375-380PSI, and mine's far from a pristine example. The 603 is a low-soot design, so it should have better wear characteristics than the 617's. What can affect your compression results is worn valve guides - they can allow the valves to "wobble".

Maxbumpo · #49 01-22-2018, 03:58 PM

I would be very careful about starting that engine if just resting in place and not bolted to an engine stand, it may twist from torque and roll over on its side. Do you have a hoist that you can also attach to help hold it upright?

It also looks like the vacuum pump is original (smooth face) and so that may be a ticking time-bomb that you'll need to address.

Best compression test is starting the engine when cold, and then getting it to run smoothly when warm.

Looking forward to hearing more about this project!

dieselbenz1 · #50 01-22-2018, 04:00 PM

I was hoping for better but will continue with a warm compression test I think.

sixto · #51 01-22-2018, 06:19 PM

If it started easily and ran smoothly when the glow plugs turned off maybe your compression gauge is iffy.

Do you know if the car sat a long time before it got to the lot and you pulled the engine? Maybe long enough for the rings to get friendly with the cylinder liners?

Sixto
98 E320s sedan and wagon

dieselbenz1 · #52 01-22-2018, 06:53 PM

Well I checked 1 and 6 with the engine at 75 deg f only a 20 pound increase wet or dry itching to run it shes ready to fire I'll strap a chain across the top of the engine chain hook, wished I had a lift. I was concerened about vibration moving it but with the chey suspension under it I'm hoping its good. My best guess it sat several years there was a fairly new exhaust system on it someone before had taken the center muffler. I went back to grab a hose but she went to the crusher over the weekend..............

dieselbenz1 · #53 01-22-2018, 07:30 PM

When I went to glow it my test lamp never came on checked strip fuse power on both sides had a spare GP relay from a 95 and the lamp came on. Waited 40 seconds she started within 2 seconds. Couldn't keep it running to long had the garage door closed didn't really expect much. Engine only slightly rocked when it first fired. Yippie tomorrow I can get the right size belt and let it warm up.

dieselbenz1 · #54 01-23-2018, 12:33 PM

She smokes ran it for 20 minutes not much reduction all white diesel odor. Think I should cut my losses and retrun it or pull and test injectors.

jake12tech · #55 01-23-2018, 12:46 PM

Quote:

Originally Posted by dieselbenz1

She smokes ran it for 20 minutes not much reduction all white diesel odor. Think I should cut my losses and retrun it or pull and test injectors.

it's worth checking the timing and trying a set of good injectors. if it doesn't work out cut your losses. I wonder how accurate you4 compression gauge is

Diseasel300 · #56 01-23-2018, 01:00 PM

With compression numbers hovering around the 200 mark, I'd be expecting white diesel smoke. I'd imagine the idle quality ain't that great either. Sounds to me like it was probably in the JY for a reason.

dieselbenz1 · #57 01-23-2018, 01:17 PM

I'm beginning to think that's the reason it was in the yard also. It sounds nice 3 bar oil pressure I'm soaking in with MMO maybe try running it in a while maybe try a purge. It idled good low on base idle I never connected the ecu. Reduced smoke when goose also one cylinder gives a good white puff on fast idle increase.

dieselbenz1 · #58 01-23-2018, 01:39 PM

Air bubbles detected in return line.

sixto · #59 01-23-2018, 02:40 PM

Do you detect coolant consumption or exhaust in the cooling system?

Is there an oil leak between the head and block just above the chain tensioner?

Sixto
98 E320s sedan and wagon

dieselbenz1 · #60 01-23-2018, 03:39 PM

No bubbles appear in expanion tank.