popping six..

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Dec 27, 2002 | 11:43 PM

ford_nut

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popping six..

OK guys
I need some help here. I posted earlier about a 300 six that pops while it runs, I checked to see that all the plug wires are intact. I also checked to see if the firing order and distributor timing is ok. Without pulling the dizzy, everything seems OK. When it runs, it pops out of the carb on a regular basis--like every sec or so. Also, when i go to start it, it sounds as if the compression is uneven...
Im starting to think that there is something amiss in the head. Can someone give me an idea where to start troubleshooting before i start ripping stuff apart unnecessarily? would a burnt intake valve cause this? I dont think a 300 has a timing chain to jump per se. i am really at a loss with this one here! HELP!!
regards
~~NUT~~

Dec 27, 2002 | 11:47 PM

Martys82

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From: Newark,DE

popping six..

bent/burnt valve

Dec 28, 2002 | 07:09 AM

ftwfred

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Joined: Nov 2002

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From: Kentucky

popping six..

Start with a compression test...This will tell you MUCH about your engine condition...
A vacuum guage does wonders too>>>>>

ftwfred

Dec 28, 2002 | 12:16 PM

Ford_Six

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Joined: Oct 2002

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From: The Big, Oregon

popping six..

I wouldn't say a burned valve- very rare on the intake. Most likely, head gasket between #3&4.

Jared

Dec 28, 2002 | 03:11 PM

heathdaily

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From: kansas

popping six..

Does the popping occur with regularity? Or does it do it sporadically with no pattern? If it's sporadic it could be a sticky valve. Either from lack of oil or carbon build-up.

Dec 28, 2002 | 04:24 PM

ford_nut

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popping six..

guys
the popping is very regular. If i do a compression test, what should I be looking for? low #'s? ect??

Dec 29, 2002 | 02:50 PM

Chas1234

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From: Quaker Hill ,CT U.S.A.

popping six..

Check to make sure a rocker arm didnt loosen up on one of the valves.
This happened to me with a 1978 300 and I didnt find out what the problem was until I pulled the engine to put in a rebuilt short block !
good luck, Jon

'75 F100 4X4
"89 F150 4X4