oil burning efi

[blainebrazil]

still working the bugs out of my efi. I have put 200 miles on it since the conversion and the oil is not even on the dipstick. The pcv valve has oil in it and i am sure this is where it is going. I made and installed the large baffle over the small baffles that were originally on the lower intake. how in the hell is oil still being sucked up the pcv.

 

[broncnaz]

Its that nice little thing called blow by. Might want to try doing a compression check that would tell you more.

 

[bronco-billy-66]

I have a well worn but very good running efi 351w. It has a good bit of blowby into the TB. I have a water seperator I modded the filter part of it with some small holes for less restriction. It should work to catch the oil. I haven't put it on yet, Just something to think about;D

 

[wildbill]

You mite pull the valve covers and see if the oil drain holes are clear. Look at the pcv valve and make sure it is in good working order as if eather is not working right it will suck oil. Back in the day they made a oil separator that pluged into the valve cover and then the pcv valve pluged into it. Good luck and have fun.%)%)%) Bill %);D

 

[blainebrazil]

what about just deleting the pcv system all together. screw in breather on the passenger valve cover fill neck, cap off the nipples on the throttle body and valve cover, and gut the pcv valve and put a breather off of it. wouldnt this work?

 

[Past_Miner]

I had this same problem on my 351W EFI conversion. I used a GT-40 lower with the small oil baffle and an explorer upper. The engine never, and I mean NEVER, used oil until I plumbed the PCV "correctly" for EFI. It didn't matter what I did, it would suck oil through the pcv on the manifold faster than I could pour it back in.

I put a vented cap on one valve cover that pulls from the downstream side of the MAF and put the PCV valve back in the other valve cover with a plug in the manifold port. I'm back to normal now. I don't use any oil and I also don't have an air management problem into the intake for the EEC to struggle with.

I must have read 100 different threads on 10 different Bronco and Mustang sites about this issue. It's a frustrating but very common problem. I can't remember anyone solving the problem without either plumbing like I did or adding a catch can. I'm sure my tired old engine does have excessive blow by but it runs very well and doesn't use oil like I have it now so I'm sticking with this vent arrangement until it's time for an upgrade to a new engine. You know, someday when I have enough spare money to throw at it.

 

[TBS-POPS]

If your using MAF fi then you need to use sealed valvecovers. the pcv in the rear of the intake will draw too much if the engine is not sealed.

 

[blainebrazil]

there are stock mustang sealed covers

 

[TBS-POPS]

Yes they are

 

[70_Steve]

I had this same problem on my 351W EFI conversion. I used a GT-40 lower with the small oil baffle and an explorer upper. The engine never, and I mean NEVER, used oil until I plumbed the PCV "correctly" for EFI. It didn't matter what I did, it would suck oil through the pcv on the manifold faster than I could pour it back in.

I put a vented cap on one valve cover that pulls from the downstream side of the MAF and put the PCV valve back in the other valve cover with a plug in the manifold port. I'm back to normal now. I don't use any oil and I also don't have an air management problem into the intake for the EEC to struggle with.

I must have read 100 different threads on 10 different Bronco and Mustang sites about this issue. It's a frustrating but very common problem. I can't remember anyone solving the problem without either plumbing like I did or adding a catch can. I'm sure my tired old engine does have excessive blow by but it runs very well and doesn't use oil like I have it now so I'm sticking with this vent arrangement until it's time for an upgrade to a new engine. You know, someday when I have enough spare money to throw at it.

Interesting!!! I had and did the exact same thing. Newly rebuilt 351 sucking oil up the PCV like crazy. So much oil that I'd get a good puff of oil smoke on startup! Built a bigger baffle for under the GT40 lower and that didn't do anything. So I used one of my old stamped steel valve covers and tested moving my PCV over to the passenger side valve cover, and that solved all my oil issues.

I'm running the stock 5.0 cast aluminum valve covers. I bought a second set and used the oil fill for my new PCV location on the driver's side, since there's a hole already there with a baffle. Cut off the oil fill to about an inch high, made a bushing to fit the stock PCV, and fabbed a plug for the original PCV location.

 

[blainebrazil]

deleted the pcv system today as i stated above. so far so good. runs strong and hasnt seemed to affect the computer

 

[broncnaz]

Usually wont affect the computer a bit. but I would hook up a PVC system anyway as sooner or later your valve covers will be a mess once those breathers get oil soaked.