[Vwdiesel] Zero oil pressure

[mikitka]

Well some of you on here might recall I rebuilt the 1.6 in my 91 ECO jetta
about three years ago or more. From the beginning it had oil pressure
issues, in other words on a cold start I got 18psi no matter what rpm
running no matter what weight oil and after driving 3 miles it goes to zero
and stays there. This is taken from the head port.  Well I have 40k on the
engine since that fine day of putting a fresh rebuild and it has been
running great. I go through a quart of oil every 2500 miles or so.  I get
lifter tap all the time and that is expected since there isn't any pressure.
Well I have been taking oil samples and this last sample which was only in
the engine for 6k miles had a iron reading of 151ppm. Looks like something
is getting eaten up and the low oil pressure is my suspect. I feel it is the
cam and lifters more than anything. 

 

I also feel the oil pressure issue is caused by the head, long store but
from previous records the previous owner had oil pressure issues when they
snapped a timing belt and had to replace the head. Ever since they put the
new head on the maintenance records have notes on them of oil pressure
issues. That is the main reason I rebuilt the engine because of the oil
pressure problems.  So I have a new head from Aluminum Head Rebuilder's that
I'm going to put on the jetta. I'm waiting for my extra set of injectors to
come back from the shop. I had a set of GTD nozzles installed and the
pressure set to 155 bar.  So basically all I will have to do is take my head
off and put this head on and hook up the injector lines and glow plug wires,
set the timing and hook up all the other stuff and I'm off running again.  I
really think this will fix my problem, if not then it looks like a short
block is in order because when I rebuilt it the first time everything was
replaced and in spec from the oil pump to all the bearings.

 

I figure a good two days and I can have the old head off, everything swapped
over cleaned up and the new head on. I was debating on not moving the IP but
for ease of getting to the glow plugs I think it will be moved. Oh one
question, I was going to do a compression test to the engine before I pulled
the head. I wanted to do it while the engine is warm. I know now to take the
injectors out while it is still hot but how long should I wait till they
cool enough to pull them and do the test.  I'm under the impression you get
a more accurate reading of the compression if it is warm than on a cold
engine.

 

Thanks,

Nick