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Discussion Starter #1
My valves ping on acceleration and on hills. Is my timing to far advanced or??
 

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Some posters may recommend premium gas to cure the ping.
I suggest you back off the timing a degree or two.
Do you know what your current timing is set to?
Where are you drawing your vacuum to advance your distributor? Ported or manifold?
Do you know how to set up the Motocraft carb? You might need to enrichen the mixture a tad.

Let us know how it goes and what cures the issue.

Good Luck, L.M.
 

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Discussion Starter #3
Timing

I am around 8 BTDC. Another kick in A$$ I changed my Rear Main seal and I think its leaking already. I loosened all the main caps and was very meticulous about everything being clean..using silicone in all the right places. Its only been two days. PITA!:pullinghair:
 

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At 8* I don't think you're too advanced. I'd look at the carb possibly being too lean.

If you Google Motocraft 2100 (or 2150) you should find plenty of info. UTUBE is another resource.

Where are you drawing your vacuum advance from?

Good Luck, L.M.
 

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Discussion Starter #5
Vacuum

I am taking vacuum from the ported site by the choke.
 

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Run advance on full manifold vacuum...

Verify your timing mark by probing the spark plug hole to verify piston at tdc...
Harmonic balancer can migrate....

Ps valves don't ping, what you hear is called detonation...

Basically the air fuel mixture is burning faster than the piston can reach tdc and get moving back down...
 

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Run advance on full manifold vacuum...

Verify your timing mark by probing the spark plug hole to verify piston at tdc...
Harmonic balancer can migrate....
That's why I asked about where you're drawing the vacuum from. That's the first thing I'd change and drive the Jeep for a few days to see if that makes any difference.

As far as the balancer migrating, that's rare but not unheard of on older vehicles. Oil and grease deteriorate the rubber that isolates the inner and outer ring and the outer ring (the one with the timing mark on it) slips and gives inaccurate timing flashes.

Let us know what you discover.

Good Luck, L.M.
 

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accelerating and On a hill you're at or close to WOT and the vacuum will be 0 either way regardless of ported or manifold source. I'd loosen the dist until it can be turned with some resistance then go for a drive and keep pulling timing until the pinging stops.
If later on you have evidence of running lean than play with the carb. and redo timing using same method.
 

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I wouldn’t completely disregard harmonic balancer migration. You may want to verify your timing with a vacuum gauge just to be sure. I’m only saying that because it happened to me.


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The reason to run advance from manifold vacuum is because it will advance at idle and more at higher vacuum where it is needed and thus retard from the idle setting under load.... all around better running engine and less likely to have detonation under load

You will likely have to retard it a little at idle after changing to get back in spec
 

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Discussion Starter #11
Vacuum

I will relocate the vacuum line. I checked the timing chain when I had the oil pan off to do the MB seal and it does need replaced so that is my next project. I have other projects at home I need to spend time on so it will have to wait in the garage for a bit.
On a separate issue I have a "clink" sound in the rear axle area when I back up. I checked the ujoints and they are good. My drive line angle is good..not sure what is going on there.
 
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