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Tips
Tips

A little ignition help needed

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The rear most valve is an exhaust valve. Look at the intake and exhaust manifolds the runners line up with the valves. The rear most valve (no4 exhaust) should be just closing and the intake valve should be just opening. One more quick check before you pull something apart. Put your socket on the crank nut and turn the engine the other direction. Keep an eye on the rockers. They should start to move. If the tensioner is gone there will be some movement of the crank before the rockers move.
If as you say no4 exhaust is wide open thats not right. Since you have gone 5 degrees after TDC it should be more closed.
The bad news is we haven't figured out what has happened yet, the good news is The rocker/valves appear to be OK. In less someone else can come up with something if it were me I would pull the timing chain cover.
 
Just paid Bob a visit and came away with this.
He has plenty of Fuel at the carb
Spark at all plugs timing seems to me good (though didn't put a scope on it)
All valves are moving.
When you start it the carb (don't know if all caught this or not) (DGV)is expelling air at the throat.
When it turns over it spins freely.
Voltmeter at coil 7.91 volts

He will do another compression test tonight with oil.
 
Time to pull the timing cover and take a look. The wide open rear most valve is not correct. Both the rear most (#8) and 7 valves should be open approximately the same, but not wide open.

Let us know what you find, and don't forget to take and post pictures.

Thanks Don.
 
I hear split overlap looks correct. Valve lash is now correct...but was it? Did any adjustment have to be made after it quit? IMPORTANT!
I'll grab some tools.
Including a compression gauge.
Dave
 
Thanks TOC, I only checked the valve lash. No adjustment made since I have owned this little beast. I just finished the "Oil in Cylinder" compression test. Still get "ZERO" in all 4 holes!! How I did this was, remove one spark plug at a time, Squirted about two teaspoons of 30 weight in the spark plug hole, attached a compression gauge then cranked the engine for about 10 to 15 seconds with the throttle wide open. Still got zero compression on all 4 cylinders. Went back and re-check two of the cylinders with an additional 2 teaspoon of 30 weight and still got the same results. Re-checked my compression gauge with my air compressor and it is working just fine. Just wish my LBC worked as good as the gauge :<(
 
Reason I asked, if you had an issue with floating valves (high revs?) or sticking valves, and piston impact enough to tweak the valves, the gap would have to be adjusted. If we can work out a time, we'll get it.
 
rcufley said:
Re-checked my compression gauge with my air compressor and it is working just fine.
Click to expand...

Stupid question : Did the gauge hold the reading after being disconnected from the air line?
 
There was absolutly zero reading on the gauge. I watched the gauge while cranking the engine with the ignition key and throttle full open. The needle on the compression gauge never moved off the zero stop. Not even a little tiny bump. You would think there would be at least a tiny bit of needle movement wouldn't you??? Again, the gauge is new and it did register 90 lbs when I checked it by pushing air into it with my air compressor.
 
I'm with Randall here, thinking we might have a gauge problem. Crank it with your finger plugging the hole. Rule of thumb: (no pun) if your finger blows off the hole, there's enough compression to run.
 
Hi TOC
No high Rev's. and I don't think the valves were sticking, however, I am not real sure about that. I should be around the house and available all day tomorrow. What ever time is convenient for you and Don is good for me.
 
bnw, That was a good idea. However, what I got is kind of what I expected. Took the plug out of #4 cylinder, put my finger in the hole and cranked the engine over by hand with a socket on the pulley nut. Result..... SUCTION not compression. That is probably why we are seeing (feeling) air being expelled out the top of the carb and not being pushed through the engine and out the tailpipe when trying to start the engine. The gauge is good.... the car is BAD. Sure wish it WAS the other way around!!
 
Ah, suction......Houston, we have a problem.

Just help me out, folks, what sized bolt holds the crank pulley on?
So I can bring one.
 
Pretty conclusive, I'd say. My guess is a sheared key at the crankshaft sprocket.
 
Dave, I think I have all the tools needed. Like Don said above, I have the 1 & 13/16 inch socket for the pulley nut.
 
My guess is tensioner. Let me know what you find. It's way too far to come help. Plus I spent 9 months at Ft Lewis I might have flashbacks. Good luck. Ernie
 
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