I got a DOHC ZC that is fully built(I got more into it than the car is worth), and everything is brand new including the oil pump. I've rebuilt many engines before and have the same ritual, take spark plugs out, disconnect spark and fuel and let the engine crank over to build up oil pressure and usually get at least 5-10 psi, but I have zero! The oil light stays lit and I have an external sensor that is good and reads zero. The sensors are good, all bearing clearances were perfect, all gaskets replaced, oil pump is brand new (put assembly lube and oil in the pump when assembled), has 5 quarts of break-in oil. I've never had this problem before on any rebuilt engines, I took off the pump allen plug and oil poured out so it has oil, but no pumping. I open the oil filler and it's dry, no oil in sight when cranking. I don't want to crank it over anymore until I figure this out. Has DOHC ZC Oil pan and pickup. Any help would be appreciated.

 

you probably did not prime the oil pump

disassemble the timing setup, remove the oil pump, and see if any oil actually went through it.

some people use petroleum jelly to prime it, though I dont like that.


Whenever I had the problem of no oil, I would overfill the oil by like 2 quarts, and turn the motor over.

If you rebuilt it correctly, it should have assembly lube protecting fiction points

Once you start seeing some pressure, drain the extra oil.

Keep us updated on how she goes!

 

There is actually oil in the pump, because when I took off the allen plug oil pours out (that how I always check for oil in the pump without taking it all off). It's suppose to have 4 quarts of oil in it and I have 5 quarts of break-in oil and about 1 quart of regular oil (thought I'd just add some more just in case). If by priming you mean fill the pump with with assembly lube and oil upon assemby, I did that. I know on other engines, you can bleed out the air within the pump so you don't have any air just oil, but don't know of any on honda's. BTW I use royal purple assembly lube, not jelly(if someone actually uses this, stay away from honda's please). Any other thoughts?

 

stay away form royal purple products


well if you primed it and no oil pressure, try and get yet another oil sender or something

IT might be pure chance your current stuff failed.

If there is oil in the pump, well, maybe the pump is bad, but on rebuilds it should be a new one anyways

 

I got the stock oil sender that is good, tried on another engine and my prosport gauge that always worked before. It has a brand new pump.

 

Then it is time to drain the oil, and drop the oil pan

double check the pickup tube isnt clogged or seperated.

a gasket might be torn or such, and no pickup tube PRESSURE= no oil going through the motor

Since electricals are okay, its definitely mechanical

 

on a limb, did you try a mechanical oil guage? I have had brand new oem pumps that were defective. Was it an eBay oil pump?

 

Yah, ebay but KMS and never had a problem. I'm just going to take it apart and see what's up.

 

Last thing you want to do is trash a new build. I bet its a defective pump or the main bearings are upside down with the oil gallie holes facing the caps.

 

Update- I took the pan off to see what's up and I noticed that oil was on every part including the sides on the top, so oil was circulating. The oil pump was full of oil I checked, and the pump was still moving with the crank. The picup wasn't clogged, the gasket for the pickup was new from honda, but I'll replace it before I reassemble it. I don't know, everything seems to be working. I've had engines the the oil pump failed and when I took the pan off everything was dry, so the oil was moving around. I might just reassemble it and try again, the only mechanical gauge I have is a fuel pressure gauge, but I would guess it would work for oil and see what that says. Have any ideas of what to check before I reassemble it? Main bearings are in the right way, holes lined up.

 

sunpro autozone, oil press guage is like 20 bux. Buy one it can be a good diagnostic tool.

 

Yah, I'm just goint to get a mechanical guage, that way I know 100% what the pressure is. I'll reassemble tonight and see tomorrow if it's good or bad.

 

Good news, I got a mechanical gauge yesterday hooked it up and still it was zero. I thought that since the tube for the gauge goes straight into the engine where oil would be I can use a little compressed air (20 psi) and blow into it. Then all the gauges worked and said 20 psi so I knew they worked. Then I took the air off and tried it again and bam! it was building pressure 20-30 psi! I tried it again later and still builds up pressure easily. I don't know what happened, maybe there was a giant air pocket, something clogged, I don't know but I'm happy my engine has pressure so I can start it up finally.

 

congrats! btw i would like too see a vid of that engine once its in a car!

 

20-30 is still kind of low. My enigne would Idle at 40 and never go under 37. Great job trouble shooting though good luck

 

20-30 when cranking at idle fully warmed up it's 50+ psi. So not a problem anymore. The best diagnosing is through guessing...thank god it worked!