no oil psi no knock
 

6-7 psi oil pressure no knocking yet!!!! at WOT 20-25 psi.. what do you think it could be?

Re: no oil psi no knock
 

Could be a bad sending unit. If the diaphragm leaks it will give low readings. Try running a mechanical guage. We test them by running a mechanical guage up to the back seat, have someone give you the readings. If you wait to hear knocking it's too late.

Re: no oil psi no knock
 

I keep a mechanical gauge in my tool box. Just get a cheep one from the auto parts store. If your mains are going out you do not want to keep running it.

Re: no oil psi no knock
 

Ditto, I got scared a couple years back with no pressure and the sender was bad......I think the spring that holds back diaphragm breaks/weakens.

Re: no oil psi no knock
 

that is on a mechanical gauge

Re: no oil psi no knock
 

Pickup tube? I would not be running the engine until I found out the problem.

Re: no oil psi no knock
 

change the filter first.

Re: no oil psi no knock
 

We need some more infor here. What motor?, is it new or newly rebuilt? Have you made any changes to filters or coolers? How was oil pressure before and when did this appear? Just not enough info here to give an intelligent opinion here.

Ray @ Raylar

Re: no oil psi no knock
 

I Agree More Info......mech Gauge, Low Oil Pressure. I Would Be Unbolting It And Pulling It......

Re: no oil psi no knock
 

Could it be a bad mechanical gauge? Admittedly , I might be well wishing here but is this the second guage to read these pressures? Maybe the gauge is bad.....sure would suk to pull it and disassemble to find that out. I agree with everyone else though if the pressure is accurate pull it and save what you can before it all worst.

Re: no oil psi no knock
 

I had a similar problem. Had oil pressure at idle but would drop to 0 at WOT. Hooked up a cheap mechanical guage from Auto Zone and had good oil pressure. Problem was the wire that attaches to the sending unit. It was a press on type. Just crimped it a little tighter and problem was fixed.

Re: no oil psi no knock
 

the motor is out and there are peices of bearing in the bottom, well any way im going to make it a 540 lets see what happens p.s. i did change the filter and oil also the motor is a 502 with merlin comp heads, stellings headers, holley carb, I bought this boat on ebay and it did not run right when it got here it is a 2000 awsome cat 26 foot I replaced all the wireing was hacked together, this has been a night mare, the hull and interior is great just the rigging and motor was a hack so 12000 later this boat will be right im sueing the seller