Oil from the Dipstick Tube
#1
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Hey guys, tonight on the ride home I did some "spirited driving" and smelt a little oil burning. When I got home I popped the hood to see the dipstick about 1/2 inch out of the tube and a little bit of oil splattered around it.
I checked the PVC and it seems to be working although there is some resistance, however I don't have a new stock one to compare it to. It also seemed pretty dry with no oil dripping out or anything. I also noticed I havent lost any vacuum and it seems to stay steady. I then left the car running and popped open the oil cap but didn't notice any air coming out.
I then popped the dipstick back in and replicated, as best as I could, the drive home. When I got back the dipstick was in place and no new oil had come out.
I also checked my oil earlier today and I suppose it's very possible that I didn't insert the dipstick back in completely.
Does the crankcase normally create enough pressure to push oil out the tube if the dipstick is not inserted properly? I've read a few threads that recommend a catch can as the stock PCV doesn't vent well enough but wouldn't this mean that the crankcase is still pushing too much pressure?
Thanks for any input you guys can offer.
I checked the PVC and it seems to be working although there is some resistance, however I don't have a new stock one to compare it to. It also seemed pretty dry with no oil dripping out or anything. I also noticed I havent lost any vacuum and it seems to stay steady. I then left the car running and popped open the oil cap but didn't notice any air coming out.
I then popped the dipstick back in and replicated, as best as I could, the drive home. When I got back the dipstick was in place and no new oil had come out.
I also checked my oil earlier today and I suppose it's very possible that I didn't insert the dipstick back in completely.
Does the crankcase normally create enough pressure to push oil out the tube if the dipstick is not inserted properly? I've read a few threads that recommend a catch can as the stock PCV doesn't vent well enough but wouldn't this mean that the crankcase is still pushing too much pressure?
Thanks for any input you guys can offer.
#11
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Well, I'm feeling a lot better about this stuff today. I just went outside and pulled my PCV. Then I wrapped my lips around the damn thing and blew it like a man (sorry there's no way to describe it without it sounding bad).
It felt like I was blowing through a straw when blowing the wrong way (manifold to cam cover). I would assume that under 7lbs of boost, with the dipstick already not all the way in, it wouldn't take much to send the oil out.
I'm not as worried about excessive blow by as with the car running there is no sign of smoke or excessive amounts of air coming from the PCV hole or the oil fill hole. Not to mention I still idle at a pretty high vacuum (around -20psi). I still want to get the compression checked but they only guy I know with the equipment is on vacation until the end of next week.
So I'm picking up a new stock PCV until I either order a 323 one or build a catch can.
It felt like I was blowing through a straw when blowing the wrong way (manifold to cam cover). I would assume that under 7lbs of boost, with the dipstick already not all the way in, it wouldn't take much to send the oil out.
I'm not as worried about excessive blow by as with the car running there is no sign of smoke or excessive amounts of air coming from the PCV hole or the oil fill hole. Not to mention I still idle at a pretty high vacuum (around -20psi). I still want to get the compression checked but they only guy I know with the equipment is on vacation until the end of next week.
So I'm picking up a new stock PCV until I either order a 323 one or build a catch can.
#14
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Not sure on the 97, but on my 99 the fuel pump fuse is under the hood.
Pulling all 4 plugs and flooring it while cranking yields the most accurate results. After my rebuild I saw 200+psi on all four. I think the min acceptable is around 125 but not sure? Also helps to have a low amp battery charger hooked up, like 2amps max and crank until psi doesn't increase anymore(usually 4-6 rotations)
Edit: I'm not sure what, if any, effect having a supercharger installed will make on the results, anyone care to chime in?
Pulling all 4 plugs and flooring it while cranking yields the most accurate results. After my rebuild I saw 200+psi on all four. I think the min acceptable is around 125 but not sure? Also helps to have a low amp battery charger hooked up, like 2amps max and crank until psi doesn't increase anymore(usually 4-6 rotations)
Edit: I'm not sure what, if any, effect having a supercharger installed will make on the results, anyone care to chime in?
#15
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fuel pump relay is under the dash in most NAs - right between the drivers legs tucked up close to the plastic trim under the steering wheel. (Basically about as close as you can get to your ******* while still being hidden) I found it the first time by going down on it, now I can get it off by feel. It should be a yellow plug IIRC. It's about 3/4 inch thick and 1-3/4" wide
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#20
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Another vote for PCV. Toward the end of my DSM years, my 4G would pop the dipstick constantly before I finally pinched the dipstick tube some to keep more pressure on it. It was also sucking in 20+ PSI with the old school super 20G. PSI is like added compression as the engine wears!
Your compression numbers look great. Anything for the leakdown test?
Your compression numbers look great. Anything for the leakdown test?