Timing jumped?
#1
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Location: Cumming,GA,USA
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Timing jumped?
Here are the symptoms:
1) engine a bit harder to crank (like way to advanced)
2) almost immediately backfires pushing fuel all over the place (thank god for flame arrestors)
3) IF engine starts, at low rpm sounds like a miss
4) at 2000+ just sounds rough w/miss
5) when turned off hear a sound almost like a pressure release
.......Is it possible its just the timing chain jumped and i'm getting the compression stroke pushing back up into the intake? Reason is, sounds similar to when i've been through this on autos...etc.
Whats the general vote on this?
1) engine a bit harder to crank (like way to advanced)
2) almost immediately backfires pushing fuel all over the place (thank god for flame arrestors)
3) IF engine starts, at low rpm sounds like a miss
4) at 2000+ just sounds rough w/miss
5) when turned off hear a sound almost like a pressure release
.......Is it possible its just the timing chain jumped and i'm getting the compression stroke pushing back up into the intake? Reason is, sounds similar to when i've been through this on autos...etc.
Whats the general vote on this?
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Guys.........thanks for the reply. Its the old, engine ran great before putting it to sleep last year, but heck, now, when that backfire happens (almost immediately), I am talking lots of fuel being pushed back.
I will pull the distributor 1st. The piece about, when I turn it off, a pressure release you can hear........very strange.
Thanks........Bob
I will pull the distributor 1st. The piece about, when I turn it off, a pressure release you can hear........very strange.
Thanks........Bob
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Checked the wires and order again (just because I did new stuff on both engines 1st thing this year), orders were ok.
Next:
1) Check points/springs...etc
2) Gonna watch the rotor rotation on start for continuity
3) Mark dist @ #1 on cap, then cranking engine to see if harmonic mark is same as when #1 on dist is there.
4) Pull distributor to check gear.
.....any other ideas.
Bob
Next:
1) Check points/springs...etc
2) Gonna watch the rotor rotation on start for continuity
3) Mark dist @ #1 on cap, then cranking engine to see if harmonic mark is same as when #1 on dist is there.
4) Pull distributor to check gear.
.....any other ideas.
Bob
Last edited by kaamacat; 06-20-2002 at 10:14 PM.
#7
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To check for a flat cam lobe you can cut the oil filter open and see if there is any silver metalic residue. Right after running the silver film should be on the dipstick also.
The thing that makes me think it is a cam lobe is the leaking down sound you are hearing and the back firing. If the exhaust valve wont open the engine will exhaust the combustion gases through the intake valve when it opens causing a backfire and spitting out any air fuel mixture in the manifold. Or with an exhaust valve stuck closed the burned gas cant escape and is recompressed and may make a leak down sound when shut down.
Maybe a broken valve spring also.
Just guesses again. I hope its just an ignition problem.
Ron
The thing that makes me think it is a cam lobe is the leaking down sound you are hearing and the back firing. If the exhaust valve wont open the engine will exhaust the combustion gases through the intake valve when it opens causing a backfire and spitting out any air fuel mixture in the manifold. Or with an exhaust valve stuck closed the burned gas cant escape and is recompressed and may make a leak down sound when shut down.
Maybe a broken valve spring also.
Just guesses again. I hope its just an ignition problem.
Ron