Oil Light Coming on. PLEASE HELP???

I got a motor that runs great.
When I start it up it is fine and once it warms up the oil light starts blinking then comes on at idle but at about 3k rpm it blinks again.
if i look into the valve cover it is still spitting oil everywhere and I am running 20w/50

I read somewhere to check the bottom end bearings so i did
I replaced the main bearings and the connecting rods bearings looked great ( I think those where changed before i got the motor recently)
I put a oil sending unit off of my old motor on it to make sure it wasnt that bc that motor never had oil issues just a bad crank on that one.

that had no effect.
I have checked the return lines and put a new filter on.

none of this has changed anything.

not really sure what to do next.

When the light comes on the motor still sounds totally fine.
not really sure what to do?

any ideas? please help.

Maybe the oil you are running is to thick. Could be cause a pressure issue. Try running some 5/w30 on the next oil change, and see if the oil light issue is resolved.

the blinking could be caused by an issue with the multifunction control, you need to get a pressure gauge and see what the pressure is actually doing

I had 10w/40 in the motor before i switched to 20w/50
The only thing that did was now it takes a few more minutes to come on.

I guessing maybe I have a cracked crankshaft.
or a crack in the block on a oil passage that is just dumping the oil back into the bottom of the pan because there is no oil in the water and it is not getting fuel into it.

I also checked for pooling in the head like it was a clogged passage or something for return.

I dont have a gauge yet.
I guess that would be my next step.

whoa way to thick of a oil viscosity

Well thanks for all the posts
the 20W/50 is recommended by the manual for above 20C temperatures.
so i am sure that it is not that.
Plus the engine has about 95,000 miles on it.

I am going to try to find a pressure gauge now and see what is going on.

Maybe I will take both motors i have and just start all over again.

At least verify that pressure is actually bad before you spend to much time/money on it. I currently live in Texas, and our temps get to 115f(268c) here in the summer. Even Honda suggest 5w/30, keep in mind the oil gets thicker in summer. This means you are running 50 weight viscosity in the warmer weather, that is 20 over Honda rec value, and 20 in the winter that is 15 over. Would not be a bad idea to start there. Not sure if foreign (outside the us) oil is rated different.

From the Honda shop manual

http://img.photobucket.com/albums/v6...psb52a821c.jpg

before you blame the engine, verify actual oil pressure, the fact that you put in new bearings and it still does it, says you have an electrical issue or an oil pump issue, both easy to fix, the usual thing that would cause pressure that low would be the mains, something you can do quick and easy, look under the radio and there should be a large module with a big plug in the back, unplug this and see if it still does it, the regular oil light will still function, verify that it comes on when you first turn on the key, the oil light flasher circuit is in that module, it detects very brief drops in oil pressure, that triggers an additional ground to the oil light circuit, I've been seeing more and more people having issues with it, that module does more then just flash the oil light circuit, but you can drive with it unplugged, your side markers wont flash eithier, or your key on chime wont work, but this is for doing a test.

Quote:

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Originally Posted by lostforawhile

the blinking could be caused by an issue with the multifunction control, you need to get a pressure gauge and see what the pressure is actually doing

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x2. You cannot diagnose anything without a gauge. Hook one up and post results.

Remember that the threads are BSP so you need an adapter (Thanks LOst for insisting on that!)

With regards to oil viscosity, I do not think you have a problem there

Attachment 5074

Unless Honda undertook a radical redesign of the A20 between 1987 and 1988 (my manual is from 1986) you should be fine. I have been running 15w40 because I like to use diesel (in fact diesel AND gasoline) oil. For the GA climate is fine although in the dead of winter it is a little bit heavy

Sorry for posting the whole page but the scanner was acting up.

A flashing oil light indicates a momentary loss of oil pressure. It can be caused by many things: faulty oil pump seals, debris in the oil pickup, broken pressure relief valve, etc. The engine has obviously been having pressure issues in the past bad enough to destroy the bearings once already and it seems the original issue remains unresolved. As others have said, you absolutely need an oil pressure gauge and UNDER NO CIRCUMSTANCES should you be driving this car until you get the condition corrected. Unless of course, you want to rebuild it. These engines can run for a very long time without any oil and a very very long time with low oil pressure. They won't complain, but at some point, you will get that tell-tale clatter and black smoke out the tailpipe. Trust me, you aren't saving any money by pretending there isn't a problem. The oil light only comes on when pressure is so low that serious damage has already been done. I have an oil pressure gauge in my dash and I wouldn't drive without it. The dash light is useless for preventing expensive repairs.

Question: why didn't you swap out the bearings as part of a complete engine overhaul? Engine bearings don't just fail randomly. There is always a cause as well as a lot of collateral damage. It's hard to correct that without extensive additional work.

the bearings weren't bad, he said he read somewhere that could have been the cause, so he changed them, and he said they were fine, and he also checked the connecting rod bearings and they were fine, so this probably rules out bearings, I think it might be an electrical ghost, he needs to use a gauge to check pressure

Quote:

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Originally Posted by Dynamaxx19

I replaced the main bearings

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he thought they might have been bad but it's the same