Go ahead and blow that motor, I have a 750 here
It's possible that the ticking is unrelated to the oil pressure problem, and it's also possible that you have a bad oil pressure sensor. There is probably a spec in the manual for oil pressure sensor resistance, so you can check it with a multimeter, but sticking a mechanical gage on it to measure actual pressure would be the best idea.
As the oil warms up the thickness of the oil decreases, so pressure drops, although if pressure drops far enough to trigger a good sensor, then you do have a problem.
I'm reasonably certain that a restriction on a oil passage feeding the head would increase the pressure at the sensor, not decrease it.
I'm going to take a look at the manual and check out the oil path diagram.
Just checked the manual, and the oil pressure sensor is indeed on the main oil gallery, and the oil feed to the head branchs off the main gallery, so a restriction on oil flow to the head would increase the pressure at the sensor.
Looks like the problem is one of the following:
(1) Bad sensor (hope for this one)
(2) Weak oil pressure relief valve spring (probably not this one)
(3) Improper oil (if you didn't put 10 wt oil in it, then forget this one.)
(4) Clearances exceed service limits (remember that 750 motor I mentioned?)
(5) Clogged oil filter (oil filter bypass valve should mask this one)
(6) Oil pressure relief valve stuck open ( I don't hold out much hope for this one)
How many miles were on that bottom end?
Post edited by: steell, at: 2006/04/10 23:08