I have a issue with my '87 RX-7. I drained the oil pan, drained the oil cooler, installed new oil filter and then filled with ~4.7 qts. I started the engine for a minute to let the oil circulate since it was reading more than full on the dipstick. I stopped the engine, and checked the oil level again and there are bubbles in the oil!? How would this happen, and what caused it?

Secondary issue. While all the oil was drained, I replaced the OMP with a blockoff plate and used some high-temp sealant. The injectors and omp lines were already removed by the previous owner, and the OMP was leaking which is why I put a blockoff plate on. Well, its still leaking it looks like. My question about this is can I reinstall the blockoff plate without draining the oil?

 

ya,you can still put Rtv or whatevr on the area around the OMP and block off plate while you have oil in the engine,
I would check Oil level though,as the car is supposed to take 6 quarts i believe.(only takes 4 if you don't empty the cooler)
Check it just to be safe,it wouldn't hurt,right?

 

Thanks for your reply.

Regarding the block off plate, are you saying I can just add some RTV around the seal without taking off the plate? Or are you saying that I can take the plate off no problem with oil in the car?

Regarding the oil, it was reading at the full mark when I added the 4.7 qts, and it is still reading at the full mark, but bubbly. If I'm understanding correctly, the oil will not go into the oil cooler unless that oil has reached some temperature, is that right? If that's the case, I would expect there to be any in there yet.

Update: If I wait a few minutes, the bubble will decrease, and will go away completely eventually.

 

You can safely remove the block off plate without draining the oil.

Take off the block-off plate. Remove all the old RTV. Apply new RTV. Re-install plate (do not fully tighten). Wait a couple of minutes, then fully tighten. Allow the RTV to fully cure (per the type/ brand of RTV, er the directions rather). Start it up and see what happens.


And Im assuming you meant:

"Regarding the oil, it was reading at the full mark AFTER I added the 4.7 qts."

 

Thanks for the advice on the OMP blockoff plate, I'll give it a shot.

About the bubbles, could it just be that there is some air being displaced in the oil cooler or something like that? How do I help the air out so I can drive it? I assume it wouldn't be best to drive it with air bubbles in the oil system.

 

You'll be fine. The crankcase is vented for a reason.

 

Remember that the oil cooler has a built in thermostat, so only running the engine for a few minutes means that the oil hasn't fully circulated through the cooler and displaced the air.
If you let the car run and get to full operating temp, your "bubbles" should disappear quickly.