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DOND
10-31-2005, 03:26 PM
Hopefully someone can help me with this problem.I took the boat out Yesterday it is a 1969 16 Holman Moody 302. When I attempted to idle it down it would just die out.I then found a loose wire on the ballast resistor.I tightened it up started the engine. It seemed fine was not dieing out.
But I started to hear a slight knock below the carb. When I would raise the rpm's it would knock faster. When I would punch it down hard it would backfire at the carb.All this was done at the dock.Do you think the loose wire caused the points to burn out?Thanks for your help.
Don

mrfixxall
10-31-2005, 04:03 PM
ck the points first,,but the knock could be a loose rocker...the backfire ,,may be related to the knock or a flat lode on the cam or a burnt intake valve could also make a backfire noise sound....

MOP
10-31-2005, 05:18 PM
Long distance dio without hearing the noise is tough to say the least, the direction I would take below.
The noise and your dying out may not related, was the boat sitting for awhile? How was it idling when you got it running? Noise high up and under the carb usually related to the intakes valve train, I would do a compression check to check for a weak cylinder. Possibly a lifter going south, stuck valve, bent push rod or things just came out of adjustment any slack caused by one of the afore mentioned will a loud tap but usually coming from the valve covers. If you find a weak cylinder pull that valve cover, check the rocker arm and push rod. Tap the motor over a little at a time try to get TDC for that cylinder see how much slack there is, with luck the adjustment just came loose if not you need to pull the push rod to check for true or go even further and pull the intake manifold to pull and check that lifter.

Phil

joseph m. hahnl
11-01-2005, 06:01 PM
Hopefully someone can help me with this problem.I took the boat out Yesterday it is a 1969 16 Holman Moody 302. When I attempted to idle it down it would just die out.I then found a loose wire on the ballast resistor.I tightened it up started the engine. It seemed fine was not dieing out.
But I started to hear a slight knock below the carb. When I would raise the rpm's it would knock faster. When I would punch it down hard it would backfire at the carb.All this was done at the dock.Do you think the loose wire caused the points to burn out?Thanks for your help.
Don

Check that the plug wires are all in the right firing order.


joe

smokediver
11-02-2005, 05:03 PM
that knock can also be a sign of water reversion ... might want to check your riser gaskets and inspect your exhaust manifolds ...

BUIZILLA
11-02-2005, 07:19 PM
backfire, AND a knock, are pretty sure signs it ate/is eating, a lobe off the cam...

Jim