Thanks Beanscoot,

I will do that! Funny thing, when I bought the truck it had it's bed full of old used parts, and some new parts never installed. I bought a new set of valve cover gaskets the other day, and after I got them home, found the guy who sold me the truck had also purchased a set, (cork ones) he never installed. I guess I'll install the newer ones as they are the type you mentioned, rubber coated, steel core, and keep the others around in case they are ever needed. I bought an air hold fitting tonight, so maybe sometime this weekend I could borrow a neighbors air compressor, grab my twist down valve spring compressor, and get started. I am planning on paying close attention to how much play there is in the valve guides. This 'ought to be interesting! Hope I don't chicken out!

 

Well, just to give you all an update. I tried to change my valve stem seals over the weekend. I found an "air hold" fitting at NAPA, which only costs about $8.00, so I decided to use air instead of the rope. Well, with the valve covers off, setting my first cylinder to TDC and pulling the plug and inserting air, I found the cylinder would not hold air, next I tried cylinder #5, same thing, and I tried once more on the cylinder which my compression tests a week or so back so the best out of all. It would hold some air, but it would slowly leak out. Every time I did this I would take a piece of hose and use it as sort of a stephoscope, and I would listen in the carb throat, exhaust pipe, but the air was always coming out through the oil supply galleries for the valves on top of the cylinder heads. Would this be known as "leak down" because of bad rings,thus making my oil consumption be caused by what is called "blow by"? I decided there was no point replacing those seals at this time as it would not help much. I put new valve cover gaskets on and drove the truck, but noticed, as it did before the valve cover gasket change, an oily, gooey, film on the side of the valve cover. I always thought it might be caused by a bad valve cover gasket, but since this is on the oil fill side, I am wondering if the crankcase isn't being pressurized by the blow by (if that's what it is) created by bad rings and it's forcing oil out the oil fil/breather cap?

 

You need to keep air pressure on the cyl while you do the valve seal, it's going to leak down after a couple seconds even with a new engine.

 

That oily film on the side of the valve cover is most probably caused by the blow-by from the rings escaping out the oil fill hole. It's coming out faster than the PCV valve can suck it in, so I would call that "excessive". So, in addition to worn valve stems (and bad stem seals), you have very worn rings as well.

 

What did the oily fillm look like?, obviously you will have a film of oil inside the engine but you said "gooey" Was it black (sludge from lack of maintenance) or white/brown (condensation or coolant in oil)

 

Thanks XLT, I appreicate your response. Yes it looks like time for an overhaul or a swap. I have to face it.....it's a basket case!

Hi Bashby! I really cleaned up the valve covers, which are chrome, and after driving about 10 miles, I saw what looked like clean, brown oil dripping down on the outside wall, of the fill side valve cover. I cleaned up my wires really well, andter about 10 miles of driving, I could see once again, an oiley, gooey, black film on those. I also appreciate you sharing your knowledge about injecting air into the cylinder head. What you are saying make sense! I guess my air compressor ( 1 HP)might not of been big enough to keep up with the demand.

I'm learning a lot from you guys!

 

The chrome valve covers are probably not original, so I suspect the PCV system might not have been hooked up properly with them. Insure it's working correctly and maybe this will fix some of the oil misting.

 

+1 on what beanscoot said, you should have a pcv valve on one valve cover that sucks air from the crankcase and a vent on the other to let fresh air in. If it's blowing oil (and air) from the vent then you either dont have enough air being sucked through the pcv or you have more blowby than the pcv system can handle.

 

BTW I thought at first you were talking about a film on the inside of the valve covers but you are talking about oil leaking outside, right?

 

The air compressor I used to change the valve stem seals was only 1/2 hp I think. Perhaps the TDC you used was between exhaust and intake strokes, when there's a bit of valve overlap, i.e. they're both open a smidge. 180 degrees from this is the other TDC, the compression stroke when the valves are both closed fully.

Try rotating the engine a whole turn and see if the cylinder will then hold air. Also, hold a piece of wire in the spark plug hole to verify that you really are at TDC.

 

Hi 'scoot!

I was wondering about that too, so I went over the cylinder #1 and set the damper to "TC", then tried it again on cylinder 1. The air would not build up, and just blow out the oil galleries on top of the heads. But...knowing me it's very possible I was not doing this right!

 

Yes sir, it's appearing on the outside of the valve covers. The PVC system consists of the valve (it's been replaced) in the passenger side valve cover and it connects with a rubber hose into an elbow, which plugs into the vacuum source on the back of the carb spacer. On the driver side valve cover, I think the oil cap ( a chrome Mr. Gasket ) is supposed to double as a vent. That's the set up anyway. Does it sound correct?

 

Yes, that's the typical PCV system; the valve regulates the vacuum from the intake manifold sucking out fumes from the crank case. The air is replaced by a vent in th oil cap, usually located at the opposite end of the engine. Most auto makers route this in through some kind of filtered air source. In fuel injected cars with a MAF sensor, this air has to be taken AFTER the sensor, since it is drawn into the intake manifold. An oil cap with a filter chamber is used in a lot of aftermarket setups where you're not as concerned with metered air.