The Jalopy Journal
Discussion in 'The Hokey Ass Message Board' started by Devmar07, Feb 28, 2018.
I really appreciate everyone' input.
Just bought a new distributor. Anyone want to by a locked out distributor?
Three thoughts that may or may not have anything to do with your situation...
Cadillac factory, in the early days of adopting robots (80s?) suddenly had a whole batch of engines using oil at a high rate.
It turned out that the machine routine didnt stagger the ring gaps, and all the ring gaps lined up, providing a fast path for oil consumption and blowby.
next - I have seen a fresh engine or two come with a cracked ring or ring land due to an employee getting a bit heavy handed during assembly.
third- In the past, I have screwed an air hose fitting in a few spark plug holes and listened carefully for the air leak noises to tell me which was leaking the most -
the intake valve, exh valve, or extreme blowby due to ring/piston damage.... it might be able to tell you a cylinder a severe ring-leak problem, but then again, so could a compression test of each cyl to see if you have one or more low low ones with some sort of ring problem.
Dono if any of this is helpful or not.
You could do a quick compression check to see if you should worry .or should give it a chance to clear up.
WHY BE ORDINARY ?
We call them DuPont rebuilds.
If you are gas fouled and pulling tons of fuel out of the cylinder you have probably washed the cylinders which will do two things one is you will loose compression and two your rings cannot seal.
DO NOT try and light it off before you know where you are at. Spin it a little bit ( like 2 or 3 seconds) with the plugs out to evacuate the cylinders. Now run a compression test on all cylinders, record your numbers. They will probably be low ( like less than 150 PSI per cylinder) now put some oil in each cylinder ( like half an ounce) and run a compression test again, record each cylinder. Your compression should have come way up.
If you washed the cylinders when you were trying to start it that would make it burn some oil and not start well
BTW I don't run a locked distributer even on my race motors. I got a Chet Smith mill here that I had the distributer curved for and it is running in the 13-14:1 range.
Good luck be sure and let us know what you find.
When I built an engine that I didn't know how long it would sit before being used, I pulled the plugs after running the engine, squirted a considerable amount of oil in each cylinder, turned it over by hand a couple of turns, installed used plugs, attached a bag with the new plugs and instructions. I also oiled the exhaust valves through the exhaust ports before taping over the ports. My recommended starting procedure was to remove all of the spark plugs, take the tape off the exhaust port, crank the engine over by hand first then with the starter to blow as much of the oil out as possible then reinstall the used plugs to start it. Once it was running clean, install the new plugs.
I wouldn't run an engine without a pcv system connected. It creates a slight vacuum in the crankcase. Pressure in the crankcase will push oil past the rings and limit oil drain back from the heads. Unless you have an engine with a road draft tube, you need a pcv system. I prefer going through the intake manifold if possible. The valve covers get a lot of spray oil in a high revving engine.
I've seen people trying to run racing engines with just breathers and they pump oil out of the breathers. They cover the breathers with rags which get soaked in oil and have been known to start on fire.
If it was my engine I would pull exhaust manifolds off and see what cyls the oil is coming out of. If not sure fire up the engine and watch then. One time this happened to me and found that I over lapped one oil ring. You can have normal compression and blow oil out the exhaust. It was easy to find what the problem was.
Hope this might help
I ran a Pontiac on my test stand for a fellow who's engine had been setting for four years since rebuild. If ran OK but oiled the exhaust and smoked quite a bit. After some break-in time, I pulled valve covers for look. I ended up pulling a few valve spring and found the seals at the top of the stems and crushed. They didn't fit the guide and just rode up and down with the valve stem. 16 new seals and all was good to go.
Another idea! Remove the carb and see if the plenum and intake runners are oily. I had a bad modulator diaphragm and the engine sucked atf from the trans
I have to take the headers off today anyways to change the plugs so i will inspect everything. The cylinders are definitely no fuel washed more like oil washed I will blow them out though and try again and let you guys know what I end up with. Probably going to be this weekend the new distributor is going until tomorrow night
You know I did notice before it ran that on a few valves it looked like a plastic piece that slid up but I thought they were just covers not really sure what they were
I've read through all this and the person that suggested the leak down test is most correct. You will waste time and have many variables with no answer with many of the suggestions. The only thing that makes rings seal is proper combustion pressure on the back side of the ring. The leak down process will tell you if you have a valve problem, no seal on rings, all by hearing where the air is escaping. You can make a leak down meter with an air regulator very simply. Your choice. http://www.superstreetonline.com/how-to/engine/htup-0812-diy-leak-down-testing/
I will definitely do that it' buried under 2 ft of snow right now because the fricken weather doesn' know what it' doing but ill do it soon and update what I find
I just did a cranking compression test on a cold engine of course but here' the numbers
They all built pressure at about the same rate. I will do a leak down test next.
You can take leakage test or compression test and be with in spec even though one or more oil rings are not put together proper. That is why I said to remove exhaust to find what cyl. or cyls. are at fault.
The headers are off right now what would I be looking for
Which hole or holes are wet on the headers? Number 8?
All of them but 2 and 8 seemed the worst
It also had the lowest compression. I'd imagine holes 3 and 5 were dry?
Actually 4 and 6 were the most dry.
If you can fire it up and watch each hole to see which cyl. oil is coming out of and how much. Also see how much smoke. It should be easy to see, A little loud so use ear muffs. Determine this first and go from there.
After market breathers clog up fast.
I' doing the leak own test tomorrow but it says to bring the engine up to operating temp then do the test but I'm not able to do that so will the test still be accurate?
It will still show you a comparison.
Low compression on the couple cylinders isnt good, but
We need to figure out what you're seeing here. If it's valve stems that's another problem. Which cylinders had the sliding covers? The oily holes?
All the holes were oily but they were on 5 and 7 they just looked like plastic covers like yellow or white in color. This thing has less than 5 minutes on it, the only other thing I can add is when I primed the oil pump I had the valve covers off and cylinder 3 exhaust rocker wasn' getting oil so I pulled the rocker and rod and cleaned them out which fixed the problem and that is the only cylinder that I set the proper lash on because I assumed the others were already set but looking at the compression numbers I think it might be a lash issue on the compression aspect.
I'e only done cylinder 1 but it' leaking at 50 percent and it on the valves. I suspect all the cylinders to be like this but I'm going to do them all obviously. This is probably because everything is new and has seated yet right
I had a friends small block FORD do this - chrome rings was the problem .
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