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Oil Consumption

J

jonward786

Member
Wanted to pick your guys' brains a bit on an issue I've kind of been ignoring for the past year or so. Ever since my 68's little 289 was rebuilt to a fully rollerized 302 I've been going through oil like there is no tomorrow. The odd thing is that no leaks on the ground and i see no smoke while driving. The engine only has about 12,000 miles on it since the rebuild and it was assembled by a very reputable local machine shop in my home town, the guy has been building fords for 30 years so he knows what he is doing.

I remember a while back I had the carb off for some reason or other and noticed a bit of oil on the inside of the intake right beneath the carb. I thought it was odd but thought nothing of it. Recently however I have been noticing i am really going through the oil, like a quart every 500 miles.

My pcv setup is correct, pcv to carb full vac on passenger and breather on driver. My valve covers have baffles but are not tall valve covers, stock height.

Has anyone had this issue. I'm beginning to think the only fix would be to go to some really tall valve covers to discourage oil from getting up and around the baffle. Do the roller rockers oiling allow bring more oil up than stock rockers?

I'm quite stumped on this one. If you're not leaking it youre burning it and I see no smoke at all and no oil on the ground. :confu
 
What do your tailpipes look like?
Are they black and sooty?
Check the pcv hose for oily condition, If so its sucking it out of the crankcase.
Pull ALL the plugs and check condition, If they are black it could be drawing it
into the intake due to poor gasket seal.
Last time I ran into the same oil consumption condition it was caused by not having the head locator
dowels in place.
 
"Mach1Rider" said:
Last time I ran into the same oil consumption condition it was caused by not having the head locator
dowels in place.
Click to expand...
Lost me on that one. I'll have to run out to the garage and take a look and see what that would cause/allow. Unless, you can explain?
 
Not having the head dowels in place allows the heads to slide outward.
While not a major amount it is enough to cause a gap at the lower part of the intake to head seal.
After replaceing 3 intake seals, I found it by doing a dry fit of the intake.
The angles were off on the intake to head.
Pulling the heads off an found only one locator in place, Installed 4 new ones
and replaced heads and intake. Oil consumption stopped.
 
That makes sense. Thanks.

You can also run into similar issues mating the intake to the engine when you've had the block decked and/or heads milled.
 
I just got off the phone with a guy from the machine shop and explained my situation. He said what it sounds like to him is the baffle in my after market valve covers is not deep enough and oil is splashing up onto the baffle and being sucked into the intake by the PCV valve. He said when oil is squirted up it bounces off the top of the valve cover so having a baffle really shallow is not good. He said the baffle should be as close as possible to the head itself to get more vapors and less actual oil.

Maybe taller valve covers would not allow the oil to even reach the baffle? I just don't know how forceful the oil "squirting" upwards at the rockers actually is.
 
:confu... I have to raise the BS flag to his oil squirting off the covers.
For it to suck up a quart every 500 miles, your pvc tube would be soaked and drain oil
out when you disconnect it.
 
Yep....he is trying to avoid other issues of a possible poor build or something. Your tailpipes may even be dripping oil at the rate it is burning.
 
"Mach1Rider" said:
:confu... I have to raise the BS flag to his oil squirting off the covers.
For it to suck up a quart every 500 miles, your pvc tube would be soaked and drain oil
out when you disconnect it.
Click to expand...

I'd have to say that it plausible. On the efi intake that I used to have on, the BBK SSI, the design for the baffle was wrong, and I was going through oil like there was no tomorrow. It got so bad that I installed an oil separator on the pvc line, and I was having to drain it with every gas fillup. I took off the top cover, and oil was pooled in every low spot on the intake.
 
I mean the guy wasn't acting shady, he recommended a leak down test as well. he just said when his camaro was going through oil, taller valve covers solved the problem. The "baffle" on http://www.summitracing.com/parts/FMS-M-6582-F301/ (my valve covers) is nothing more than a flat plate screwed under the opening, and the added oiling of the rollers rockers i could easily see oil getting up there easily.

What about those elongated filler tubes. I wonder if those would reduce the oil that can get sucked up by the pcv
 
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