well the leak on the 327 has slowed, but its still there. I have replaced the intake and valve cover gaskets. Made sure the seal around the oil sender was tight, and made sure the seal around the distributor and dipstick were good but im still losing oil. i can run around town for 3 weeks and not lose a drop, but after 90 miles on the highway i lose 2 quarts. the bottom half of the drivers side of the engine compartment is covered in oil. it seems to be dry around the intake and vlave covers but the last 2 spark plugs and steering shaft are covered in oil. could a high constant rpm cause a oil leak? could it be leaking from the head gasket? I AM NOT BURNING OIL. there is no smoke and coolant is not low so i thought this was a stretch, but you never know. wouldnt the car run poorly down one cylinder? should i put a compression guage on it and see if i have one low cylinder? could a oil leak at the filter cause this?
Go to a quality auto parts store and ask fo Trace leak Powder. Leak Tracing Powder is an easy way to locate troublesome fluid and air leaks. Merely spray this highly sensitive powder in the area of suspected leakage, and Leak Tracing Powder will quickly reveal the location of any leak. Excellent for location of any leak. Excellent for locating air, oil, gas, transmission fluid, etc. Clean and dry the Engine frist. Dive at the speed that it leaks at, for a short bit. Then check to see where it is coming from, My have stop and look a couple of times.
Does the engine have a draft tube to vent the crankcase? If it does, make sure the breathers and the draft tube aren't plugged. If you're running a PCV sytem instead, do you have stock or aftermarket valve covers? If aftermarket, try running a set of stock covers for a while. Some aftermarket valve covers aren't baffled properly. If possible, get the correct ACDelco PCV valve for it. Some enfgines are fussier about this than others and don't like some non-OEM valves. Also make sure the breather and vent hoses aren't plugged, or have gone soft and are collapsing at high vacuum.
I've had the oil sender to pipe adaptor leak, they crimp the unit together at that point. I read that you do have a gage sender? Blow-by?
i have the stock valve covers.... there is a hose running from the rear of the block to the carb with a pcv valve in it. the oil filler tube has what looks to be a non vented cap (should it be different). there is a sticker on the filler tube about soaking the filter in kerosen, but my cap has no filter. i am fairly sure that im not leaking at the rear of the intake or the oil sender. below you can see the pcv line by the dist. and the filler tube and chrome cap.
one more question. one the second picture between the dist and the carb there is a gold threaded fitting with a white plastic insert.... what is that?
yes it has aspin on filter.... but i hadnt thought to try to tighten it.. wouldnt that be nice. i really should try the simple things first. I ddi have a major leak from the intake to start with
The other half of the pcv system is to run a hose from a baffled hole on one valve cover to the base of the air cleaner - duplicating the GM system completely. Also make sure your pcv valve is not stuck. Fill tubes or holes should be sealed (unvented). Charlie
Oil leaks are like pissing in the wind, they blow everwhere. Do your self a favor, and get a can of Spray Trace leak Powder. Just a few buck's and well worth every pennie!
Take the oil fill cap off and take it for a ride. With a pcv system you need an in and an out. You have the pcv valve to the draft tube hole. You need a vented oil filler cap or valve cover with breathers in them.
You need a breather cap instead of that sealed cap you have now on the oil filler tube. That cap was used with valve covers that either had a breather cap or had a hose that ran to the air cleaner. Sounds like you have excessive pressure in the crankcase,broken rings ?? Change out that filler cap and take a compression test and see what you get.
The early 327's used a canister type filter, there is an adapter kit to switch them over to a spin on type filter, they (the Adapter) can leak it wouldnt be the filter leaking but the adapter plate above the spin on filter.
It should have a breather on the fill tube and also make sure the PCV valve is going in the right direction. It's probably trying to vent out through the dipstick.
That's not the way the PCV's in some of the 327's were hooked up. My '65 Chevelle 300horse was set up just like this one. I would double check the oil filter spin on adapter to make sure the gasket is seated properly. If this engine is early to mid60's it had a cartridge filter from the factory but there were after market adapters made to convert these to spin on. The old cartridge gasket was used to seal around the adapter. I had trouble with mine leaking from time to time.
does the engine have screw in rocker studs? if so the intake rocker studs have to have sealer on the threads into the heads.
check the 2 threaded plugs on the back of the drivers side of the block. One is just under the drivers side head. You can only see half of it with the head on. The other one is just above the oil filter. I chased a leak for years and finally found out the it was coming from these plugs. Even after I put new plugs in with sealant, they still leaked. I had to use JB weld to to finally seal em up. Haven't had a drop on the ground since. Oh, the motor in question is a '63 283.
You said running around town,no leaks,just on long trips,check your filter real good .even though it might not be loose it could have a pinhole that would only show up at high rpms,had this happen on a 327 and not to stir the pot but don"t buy a FRAM just because its orange.
you might want to put some spreaders on the lower valve cover bolts. might not be the problem but always a good idea.
I agree. Also see if there's any area on the block that has a bolt hole with nothing in it. Get yourself some s/s allen head plugs and start filling all the open holes.
This may not fix your oil leak, but something looks hinky with your crankcase venting. You say the hose from the PCV valve goes to "the rear of the block". What's it connected to, or is it just open to atmospheric pressure? When the engine's running, can you feel any vacuum at the end of the hose? If there's no vacuum there, the valve is bad or installed backward and you have no crankcase venting. If there is vacuum at the end of the hose, and it's not connected to anything, it's creating a vacuum leak and it'll cause the engine to run lean. And as best as I can see the crankcase still isn't vented. I see no breathers in either valve cover and you state your oil fill cap isn't vented. As a result, you're getting a build up of pressure and turbulance in the crankcase, especially when running at high speeds. It can get bad enough that it will try push v/c gaskets and intake manifold end seals out of place, and push out oil as well. It can also push oil up out of the dipstick tube. To reduce this pressure, the PCV system keeps a slight vacuum in the crankase and helps draw out blow-by. But it won't work properly if the crankcase is an otherwise closed system. That's why there has to be a vent hose in the valve cover or a vented oil fill cap. There has to be a place for clean outside air to be drawn into the crankcase where it purges the blow-by and is drawn thru the PCV valve and hose which pulls it back into the intake. Here's a diagram showing a generic PCV and crankcase breather system.
The '62 327 in Corvettes had a draft tube at the rear of the block, but I think the passenger cars used an adaptor that took a hose with a pcv to the carb base or to a port in the rear of the intake. What ClayMart shows is what I was alluding to in my earlier post. A pcv system set up this way with everything else sealed well will produce an extremely dry engine. Charlie
some of the front motor mount holes are tapped all the way threw i believe it is the top ones(incidently u ca n run a longer bolt threw the fuel pump side and it will hold the rod up to change the pump,just dont tighten it two much and bend the rod) but if there are no bolts in these holes or are lose they will leak,but i agree i think u you have a venting problem
With the setup you're describing above, didn't the adapter pass thru the back of the block into the lifter valley? Wasn't there a baffle back in there in the valley, kind of a small juice can affair packed with a coarse steel wool material? I could see that getting plugged up on an older engine with enough miles on it. If it's not plugged up, and those are the correct valve covers for that engine, then he might just need the right, properly vented oil fill cap to get the crankcase venting back in order. Might not fix his oil leak but it would be cheap enough to try and ought to be fixed anyway. The more I look at the PCV picture I posted above, the less I like it. Makes it look like somehow the breather inlet air somehow enters thru the valve cover and ends up in the cylinder! It would actually pass thru the holes in the head casting for oil drainback and around the pushrods and then into the crankcase and lifter valley. After that, the rest of the picture looks OK.
ClayMart, yes there is a baffle at the rear of the lifter valley - juice can like is a good description. An oil fill tube with a hose barb to allow a hose to vent to the air cleaner base or side as in the factory air cleaners would work good. Your illustration is good and is made better by your further description. I recently acquired an early 60's 283 +040" bare short block for a project and had a devil of a time tracking down all of the tin stuff until I happened to stop at a shop where they had just torn down a 283 that had been frozen and the block split on both sides. Got all the tin parts including that baffle and the outer adapter. I passed on the std. bore 283 forged pop-up pistons as the chances of finding a really good std bore block is pretty iffy. I never figured all that stuff that was so plentiful when I was a young man would disappear so completely. Charlie
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