I got a GSR motor freshly rebuilt with all oem honda parts. Motor starts up and idles perfect. The only thing wrong is the oil light would flash and now it stays on the whole time. I have double checked the single wire at the sending unit and I have also installed a brand new oil pressure unit as well. Before replacing the unit the oil light would come on after the motor has been warmed up for 10 minutes. It would stay on when the idle came down under 900 rpm but then flicker on and off while it idle at 1k. After swaping in a new pressure unit the light comes on and stays on after 10 minutes. I have changed the oil and oil filter already but made no difference. Can it be a bad oil pump? How can you determine if the pump is going bad or not working correctly? Overall the motor sounds healthy and idle's perfect. I'm out of ideas and wanna confirm the problem before I go tearing down the block. Please help with any suggestions or past related issues. Thanks in advance.

 

Have you tried an actual oil pressure gauge? Could be oil pump or bearing clearance issues. Was the crankshaft serviced prior to assembly?

 

I'm about to buy a oil pressure gauge tomorrow. The crank and block was checked and assembled at the shop. I just picked it up and finished the install.

 

The machine shop assembled and checked all the specs and did the micro polish, hone, and bearings clearances for the block.

 

I've found this on manuals

 

I've read all the manuals and searched on line about this issue but none of them really stated a fix. Every one says oil pressure switch but that's been changed. I need input on oil pump failure.

 

You need an oil pressure gauge and actual engine pressure reading.

 

Yes, before any dismount u must have to monitor your oil pressure in order to say what's wrong. How can u be sure that you dont have any oil conduit obstructed from and mochining debrees? For ex i mean...

 

Going to install the gauge today. I'm sure there is no oil conduit or debrees because the motor is freshly assemble out of the shop. Like I said, this motor has less then 5 minutes of idle.

 

yes let us know good luck!!!!!!!!!!!

 

Alright guys. At cold start the gauge reads 25 psi at 1.5k rpms untill it warms up then goes to 8 psi at about 1k rpm. Oil light still hasnt come on yet. I hold the rpm at 2k and I get 20psi. Try it at 3k rpm's and I get 35psi. Now I let it idle after it warms up and the oil light comes on and it stays between the zero to 5 psi mark. I can see the air in the line where the oil has stop. If I rev it back up I see the oil travel in the line back to the gauge and the psi reads the same except this time the oil light flashes. Every time I let the engine idle I see the oil in the line flow back and there is a air gap in the line to the gauge. For sure i KNOW there is oil pressure lost somewhere. What do you all think? First oil light problem i've ever had so this is new to me. Any other suggestions?

 

Did more research and I'm lending towards the oil pump. Every one else keeps stating that it could be either crank main/rod bearings or oil pump. I'm gonna trust its not the bearings because the motor is freshly rebuilt with new bearings and seals. The only thing used was the oil pump but it came off a running car. The motor doesn't make any knocking or ticking noises. It sounds good and idle perfect. I'm stumped.

 

unplug oil pressure sesnor. and install gauge. never have to worry about the inaccurate oil pressure light again

 

I installed the gauge and it shows low oil pressure so the light is accurate.

 

any other suggestions??

 

low oil pressure as in what

 

is oil pickup clean? i would replace oil pump and check pickup

 

Not much else you can do with out dropping the pan. I suspect the main bearings, based on the high pressure at cold start. The rebuild may have gone wrong. Drop the pan and plastigauge the bearings(you can do it in car) and see if the clearances are right. If you are unsure of this procedure, contact your local shop and see what they charge to check it for you.

 

I'm gonna drop the pan tomorrow. I'll keep you guys updated on what I find. Thanks for all the input.

 

UPDATE-

I pulled the oil pan and clean the pick up which wasn't dirty but did since I was there. I also thought it could be the oil plug on top of the block between cylinder 2-3 so I started to pull the head. After pulling off the cams I noticed there was a plug missing by the distributor cam journal so I looked in my box of screws from the build and found one Allen head bolt screw. I tighten it up and put everything back together. Started the car and oil psi read's 60 at cold idle. Drove it around the block and oil pressure stays above 35-65 psi after after 2k rpms. At warm idle it reads 8-12 psi. So far no oil light. Hope my experience will help someone in the future. Thanks to everyone for trying to advice me. I really do appreciate it.

 

See, you were blaming the poor oil pump for nothing!! Good job, glad you found the prob.