Rubber oil cap woes

Dean GXE · Aug 14th, 2003, 05:56 AM

Has anyone , especialy guys with modifeid E engines found that the rubber oil cap does not do a good job at keeping the oil inside the engine.

On my Sentra the car will run very dry (no oil leaks) for weeks on end. However just one fast run where I am downshifting and reving to the limit and oil trickles past the oil cap. Now I know you will say I have blow by , worn rigns and all that, but the car does not lose any significant amount of oil. I change oil every 3000 miles and that`s it, no fil ups in between. Also no oil is being burned (my pearly white exhaust will tell you that)

My only conlusion is that the oil cap is not sealing as it should. Can I find a better one? Where?

Blown how does the rubber oil cap do on your high compresion E16?

Myetball · Aug 14th, 2003, 07:38 AM

Once I bought a new one at the dealer I didn't have any trouble. The old one was hard as a rock. Check for a clogged PCV valve.

MyClunkyAss12er · Aug 14th, 2003, 09:03 PM

when i went ot change my oil thsi last time my cap jsut tore aprt when i tried to pull it off so i installed thsi nice looking crome one that fits really tight and wont tear! and even better it looks good and im not one thats fond of crome! go get one and pep boys or somthin.

blownb310 · Aug 14th, 2003, 09:56 PM

Quote:

Originally posted by Dean GXE
Blown how does the rubber oil cap do on your high compresion E16?

***** It does just fine. Like most other parts on the car, the oil cap was replaced with a genuine Nissan cap. I never had a problem with it. However, I have a crankcase evacuation system on my E16. It is commonly used on racecar engines, and that's where I got the idea. I'm pretty sure you can get a kit from Summit or Jegs. I pieced mine together myself. They are reputed to save some HP by decreasing the amount of windage [slung oil] from creating a parasitic drag on the crank counterweights. Basically, it consists of a 3/4" diameter threaded steel fitting welded in the header collector at a 45 deg. angle. To that threads a one way check valve, [I used a junkyard air pump check valve from an old Buick V8]. To that you connect a length 5/8th heater hose up to the [larger of the two] breather fittings on the valve cover. Plug the other fitting. So when the engine is running, the exhaust gasses flowing through the header collector pass this 3/4" orifice [in the welded in fitting], and a vacuum is created. You are using this vacuum to "suck" the crankcase vapors out of your crankcase, thus the term "crankcase evacuation". This is something that would not pass an smog emmisions test, if you live where they are checked. It's intended for race cars.
Aren't you glad you asked?

MyClunkyAss12er · Aug 14th, 2003, 11:11 PM

yay! more useful info for building a nifty keen engine! blown, knower of all things i forgot.

blownb310 · Aug 15th, 2003, 08:02 AM

I have cut and pasted this latest technical peice for my E-series modifications sticky. I couldn't see it getting buried in the bowels of a forgotten thread somewhere. It's a classic.

Dean GXE · Aug 19th, 2003, 04:32 AM

Thanks Blown. How does that differ from the PCV system?

blownb310 · Aug 19th, 2003, 08:03 AM

Quote:

Originally posted by Dean GXE
Thanks Blown. How does that differ from the PCV system?

***** It differs in that a PCV system reburns the crankcase gasses, and the crankcase evacuation system blows it out the tailpipe.

Lazarus_023 · Aug 19th, 2003, 05:07 PM

Quote:

Originally posted by blownb310
***** It differs in that a PCV system reburns the crankcase gasses, and the crankcase evacuation system blows it out the tailpipe.

yeah. you can give the suckers that little puff o' smoke right before you waste 'em with your "tired-ol', beat-up, high-mileage, oil-burnin'" B11.

ROFL!