diesel question

I have been out of the game for a while , but I dont think things have changed all that much , if you think the specs are below what they should be , you can do a wet compression check with a diesel engine , the same as you do with a petrol engine , to check whether you have valve problems or rings . You have to have a compression tester setup for a diesel engine and fittings to go with it , and you dont need to use much oil , otherwise it can lock up on you and cause damage to your engine . I found that using a pyrometer on the exhaust used to give a lot of good info , but nowdays they might have more mod cons to be able to do this testing :) 40psi lower than the other 3 is a bit too much . Sometimes listening to the exhaust can help , its amazing what you can pick up :)

good luck :)

You can but you just need a pressure gauge that reads to like 700+PSI and it clamped into the injector pocket, Mabey less with just a little 2.8 diesel.

But it's most likely either valves, rings or possibly damaged piston if it's only down on one cylinder.

Have you done a blow by test, this will rule out rings if OK??
What are the other Pressures, are they all with in spec or below or is No 2 the only one that is down and all the others are reading with in spec.

Check Loose head studs, valve clearances, week valve springs.

Cheers

You might consider using some CEM treatment.

If you have sticky rings on the one cylinder, CEM will free it up, and give the rest a good cleanout as well.

It would be highly unlikely to make things worse.

No affiliation, etc.. Have used it successfully in the past.

Guzzi.

to determine if the test is correct, with the motor running loosen the injector pipes one at a time and note how much difference it makes, if the drop in revs is the same for all cylinders you are ok, if its not the head has to come off then you will know. To check for broken rings with the head off just place some oil on the bore and turn the motor over by hand, when the piston goes down there should be a full uniform circle of oil on the bore. Good luck Eric.

Hi Pete, Mate every diesel I have checked for imbalances in compression between cylinders has been by doing a wet test the same as a petrol engine. There is no problem with putting a small amount of oil down the pot of a diesel engine as long as there is no injector or lines connected. Only remove the injector from the cylinder you are testing but have all other injector lines disconnected this will ensure the engine will not fire up. If the compression increases look at ring wear.
If it stays the same it will either be worn valves seating or Head gasket. Make sure the valve clearances are correct prior to doing the test. It is a major cause for any diesel to lack power.

Cheers Worm