my compression numbers :)
 

om 607960 6 cyl turbo 1987


#1 300
#2 340
#3 300
#4 320
#5 340
#6 345

#3 was kind of slow to build the test was done cold, engine runs fine but starting is another issue, unlike my hyundai diesel which starts one crank sometimes (indirect also)
the engine smokes a bit at idle white smoke, the valve cover tube is broken and if i plug it with my finger it builds pressure rather quickly
havent done a leak down as yet but i have found that soaking injectors in vinegar brings them to a brand new finish.
how are my numbers
anyone know the size of the tool for that funny shapped star head bolt?

you have a range of 45 psi, which is too much...

ouch
guess its time for a leak down

No point, your range is waaay out of spec, it's spanner time, let the dog see the rabbit...

The ONLY check to make first is pop the rocker cover and make sure all the tappets have some clearance.

Assuming 15 psi is atmospheric, 300 psi is theoretical 20:1 CR, and 345 psi is theoretical 23:1

So #1 and #3 are buggered and #4 is borderline.

It's spanner time.

Actually, BEFORE you get the spanners out, get some very soapy water and spray it over the glow plugs and injectors and crank the engine, any leaks will blow bubbles, no bubbles = no leaks so check the valves have some clearance and if they do get the spanners out.

actually i remember seing bubbles being blown on one of the glow plugs, i think i had wd40 sprayed on it, i didnt bother to check the others
whats the remedy for leaky glow plug threads?:o

Just a quick comment, excellent suggestion.

You need to have done the compression test with a warm motor. I would redo after a good run.

If it is a OM603, valves do not need adjusting.

agreed
:D

Hydraulic lifters can lock open, valves can recess, even camshafts and can develop problems...

as difficult as it is on the 603, (not 607 like you stated above...) you need to redo the test with the engine warm before condemning the motor...
the star bolts are "tripple square" 12mm last I checked.

OK, hostage to fortune time.

In another thread I said that hot compression tests are a waste of time, all you need is a cold dry test, a cold wet test (one squirt of lube oil from oil can prior to inserting compression test nozzle) and if you want to be anal a blow down test at two crank positions with a regulated 10 psi supply.

Hostage to fortune because matey has his cold dry numbers.

If he now does cold wet and publishes the numbers, and then warm (warm always dry, never wet) you'll see.....

Precisely how anyone hopes that a 45 psi disparity on two cylinders is going to go away on a hot engine test and give six near as dammit identical results is an exercise for the reader to speculate on.