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Well, serious drawback :[

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regularman

regularman

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It was 81 here today and I convinced the wife to go for a ride with me on the parkway. She wanted to go by walmart first and we did and it ran just fine. We got on the parkway and rode for about 20 miles and over the radio the wife said she thought she heard a noise. I did not hear it but then I noticed the car had very low power. We found a place to pull off and I raised the hood and checked plug wires and found one plug really loose. I thought this was the problem and tightened it up, but still it missed on one cylinder. I drove it back home on three cylinders and replaced the plug when I got home. Still missing, checked spark and it is good. Took off valve cover and verified that there is lash and that the valves are opening and closing. No 2 cylinder continues to miss. I checked the new plug after running a bit and it seems to have oil on it. I left the plug out and started it for a second and it blows all kinds of air out the hole. I don't know what is going on. It is possible that I burned a hole in a piston? I have leaned it out a bit, but have not run it hard. when all the plugs are in and it is running on 3 I don't see a whole lot of blowby coming out the tube in the front. Anyways, I am tired and gave up for the evening. Very down now. I think I am going to have to pull the head tomorrow. I need to think.
 
Of course it will blow air out the spark plug hole. That ain't it.
 
Yeah, I just did that to see if it would blow air out. I need to get my dads compression gauge and check it with the other cylinders. Shoot I hate to tear that thing back apart. If its just a valve that might no be too bad. I figure if I had burned a hole in a piston there should have been lots of smoke and there was none. This car is breaking me. The whole reason I went through it was so I would not have this crap.
 
What does the #2 contact inside the dist cap look like?
 
Trevor Jessie said:
What does the #2 contact inside the dist cap look like?
Click to expand...
It looks ok. I can pull the wire off #2 with it running and then get it back close and see a nice blue spark coming off of it. I swapped plugs with #1 that was running good just to see and #2 still missed.
 
There was absolutely no spark knock going on, I always am sensitive to that and I know the damage that causes. I have burnt holes in piston before with spark knock, playing with engine timing on 2000 fords. This seems so different, with a spark knock burnt hole there is evidence on the spark plug. I just got standard valves, maybe #2 exhaust valve just broke?
 
I hate to say it but your info sure points to a holed piston
or stuck - bent valve. but you said all valves were free and poped lash so.. burnt valve maybe Most likly holed piston pulling the head will tell.
 
I would think a holed piston would mean a lot of pressure in the crankcase thus lots of oil on the ground.
 
This is one of the areas a leak down tester is the tool to grab and start to pin point the problem ahead. It will tell you many things. Very quickly.
"Dug"
 
jlaird said:
I would think a holed piston would mean a lot of pressure in the crankcase thus lots of oil on the ground.
Click to expand...

Yup.

Suggestions:
Bent pushrod
Flat cam lobe
Burned valve
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Is that one of those deals that put air pressure in the spark plug hole and you listen for leaks?[/QUOTE]


Yep. They are easy to make. How I made mine was: I bought tee fitting, an air pressure gauge, an air hose, and a couple of male air fittings. I busted the "guts" out of an old spark plug and welded a male air hose fitting in. If you don't have access to a welder, you may be able to tap and thread a fitting into the plug body. Next I mixed up some JB weld putty, put it in one side of my Tee, and drilled a teeny tiny hole in the putty once it dried. Next I fitted the pressure gauge and fittings to the tee such that the side of the fitting with the JB weld is the side that the air compressor connects. So when you are ready to test, you will have your modified spark plug in one cylinder, and your gauge rig connected to an air compressor putting out 100 psi and standard air hose connected to the other side of the gauge rig. At this point your gauge rig should be air tight and the guage reading 100psi.

To test your cylinder, turn the motor until the piston in question comes to roughly TDC. Having the plug fitting in the cylinder helps because you can hear the air whoosh out of the cylinder. Once at TDC, put the car in gear, engage your emergency brake, connect your guage and check the pressure. A good cylinder will show a roughly 5-10 psi drop. If the drop in pressure drop is on the higher side, you can use a piece of hose to pin point the leak. If you hear a loud hiss in either the intake or exhaust manifolds, suspect a problem valve. If you hear the hiss in the next cylinder, suspect head gasket. If you hear the hiss in the block listening through the dipstick hole, suspect rings or piston.

If valves seem to be the culprit, try this little trick before dismantling your head. With air pressure applied to the cylinder, tap the rocker arms with a hammer. Frequently, this will remove carbon and deposits that may be preventing a good valve seal. I have seen cylinder pressure rise from 70psi to 90psi using this technique.

I know this seems like a long, involved process, but this is hands down the best trick I have learned from the BCF. Once you have your test rig built, it delivers quick and CONCLUSIVE evidence of cylinder troubles. NO GUESSING.

Good luck.
 
I slept late today, long day yesterday and bad dreams last night of the midget in pieces. Here is another bit of info. the plugs that I pulled out, including the one that was not firiing and had some oil on it, all had a light brown color on the electrode. This should be about right with the fuel mixture. I wonder if it could be the head gasket? I was just about to do my 200 mile oil, filter change and head retorque.
 
Could very well be a gasket.

The only way to find out for real, as you know is to pull the head.
 
Discovery, Checked compression on #2 and it was 75 and number 1 was 150. Pulled the head. Pistons fine, valves fine, head gasket blown big time. I see what happened after checking it out. It is the wrong head gasket. Its been so long I cannot remember where i bought the set, but the head gasket appears to be for a Mini or a Bugeye. The gasket hanged over the cylinder and there is a hole in the gasket between 2 and 3 that was stamped in there, but the over hang left almost no gasket meat to seal between the cylinder and that hole. Pics in a minute.
 
MVC-362F.jpg
MVC-363F.jpg
MVC-364F.jpg
MVC-365F.jpg
 
At least now I know what the problem is and that it was not a burned piston or broken valve or due to my carb fiddlings. I am ordering 2 head gaskets, one for the emergency spare. I did this for a pickup truck once that had blown a head gasket and I thought might happen again. Just peace of mind.
 
Cheap insurance indeed!
Sorry you had the problem, but so glad to hear it's a fairly easy fix!
 
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