LUVTruck.com

i was messing around with the pup today, and i noticed when i took the oil fill plug out that there was alot of crankcase pressure. it was blowin alot of oil outta the fill hole too. there was a lot of air rushing out of the fill hole.

is that normal for the motor or do i have a problem? i have a pcv that goes to my weber air filter, but ive never checked to see if it was workin. anyone got any info?

_________________
"but its that gut feeling of you're drawn to what feels right for yourself and what you're passionate about..."

Sound like pcv is pluged or there is no vCUUM IN ENGINE. When you unplug pcv and put mfinger on should be vacuum.

_________________
1980 Luv 4X4
another 1980 luv 4x4

If you are worried you have a worn motor, do a leak down check. Compression tests are allmost a thing of the past. A leak down test will pinpoint what is worn and to how much it is worn.

_________________
Certified pilots, looking down on people since 1903.

what the heck is a leak down test?

LUVs don't exactly have a PCV valve like a lot of motors. There is a large inlet on the top of the valve cover that leads to the air cleaner, and a small line coming off the side of the VC leading into the intake manifold. That small line should have vacuum on it in most situations. The PCV valve in this case is basically integrated into the port on the manifold. If you pull it and find no vac at all, hose some carb cleaner down it and see if that clears it out. Since it is such a simple setup, it rarely plugs up. The other large line should normally only let air into the crankcase, and not much should dump out into the air cleaner. Its purpose is to pull air into the CC, clean air from behind the air filter.

As for is it a bad thing, both mine do it to some degree. Make sure the lines are clear and other than that there is not much you can do about it. There is also a line coming off the oil pan that leads up to the fuel tank vapor system too. That one also comes into this and should be looked over too.

A leak down test is this:

You need a leakdown gauge set. The set has two gauges. You hook up air from your compressor and adjust the regulator on the gauge set to 100psi. You then get whatever cylinder on the motor to TDC with both valves closed. You now would insert a hose ti the spark plug hole as if you are doing a compression test. that hose would now go to the leakdown gauge set. Air now would fill the cylinder and the second gauge would read how much air is leaking. If the gauge is reading 10 psi that would be 10%, if the gauge is reading 25 PSI that would be 25% leakdown. Lets say the gauge is reading 25%, you would now listen to the carb, tailpipe, and the oil filler. where ever you feel or hear the air that would indicate what is worn in your motor. So if you heard it in the tailpipe, its the exhaust valve and the same for the intake and oil filler.

_________________
Certified pilots, looking down on people since 1903.

with a weber carb and headers how advaced in timing do you go?

Farmer, the reason you are getting blow by, is because of your rings How many miles are on the motor? It sounds to me like a rebuild is in order.

well, the motor was rebuilt 11,000 miles ago. i even talked to the guy that did it. so i dont know. my dad looked at it and said that what it was doin was normal. theres no crud in the line thats goin my airfilter and it aint doin anything else wierd.

_________________
"but its that gut feeling of you're drawn to what feels right for yourself and what you're passionate about..."

Well, I took my truck to the shop a while back, because it kept fouling the plugs , and I asked if it was the rings not being seated yet, and the owner told me no, because, if it were the rings, it would have a lot of blow by, and would be spraying(pushing) what ever, oil out when I took the oil cover off the valve cover. I hope for your sake he is wrong, but it kinda makes since. How do your plugs look, and does your motor use oil? What about smoke?

well the plugs are a nice toasty brown, it doesnt use any oil, and doesnt smoke a bit anymore. it smoke a little when i first got it, but that prolly cuz it had been sittin for like 2 years, and that was only on startup for like a minute and then it was gone.

_________________
"but its that gut feeling of you're drawn to what feels right for yourself and what you're passionate about..."

Hmmmm!! well we will have to see what 800 has to say!!!!!!

LOL. well he did already post in the thread

_________________
"but its that gut feeling of you're drawn to what feels right for yourself and what you're passionate about..."

My 78 has a lot of pressure coming out the oil fill also. I was told in another topic here some time ago, that there is quite a bit of air blowing out that filler hole when the eng. is running and the cap is off. And my truck runs great except for the knocking wrist pin. It even just passed Ca. smog.

_________________
OK, I'm over it. Where's the beer?

this is normal. Remeber that its an OHC engine so oil is injected at 45plus PSI into the valve cover area. I have this same thing happen whith my engine, i left my fill plug off and took a drive, 2hours at highway speeds and lost about 1.5 quarts of oil. Just normally i will loose a little oil at sustained 3,000rpm+ (about .25 quart every time i drive to Spokane) through the breathers. Im perty shure this is only becouse im not running the vac line from the oil pan so i probly have a bit more preasure than the rest of you guys. All there is as far as PCV on the G engines is a vac line to the intake that goes to the top of the valve cover.

_________________
1980 LUV 4x4, going under re-construction...

I run my timing at 12* BTDC

_________________
1980 LUV 4x4, going under re-construction...

Didnt even see that one