Ok... Here's the history.

I have a 1982 Ford F-150. A couple of months ago it started dying for no apparent reason. I went through the simple fuel or fire check. I replaced the fuel filter, spark plugs, rotor, cables, and coil. Still the problem persisted... So I broke down and bought a rebuilt carburator. Probably my big mistake. I was able to install the thing ok, but there is one vacuum on the rear left of the carb that I don't seem to have a hose for... So I plugged it up. I also had some problems getting the mixture right (I think it may still be off). It also seems to shift a little earlier than I expect it should. But my biggest concern is the clacking sound coming from the engine. It's loudest when the engine is cold, and it occurs at the high end(RPM) for the gear I am in (auto trans.). This didn't happen before I replaced the carburator. I guess my question is... could the mixture that the carb is adjusted for be the cause of this problem? If not, is it just coincidence that this started happening right after I replaced the carb?

I could really use some help on this...

Thanks,
Mike

 

Is it a pinging or spark knock like when you put lousy fuel in it? Or is it a mechanical ticking, and can you make it do it in the driveway with the hood up?

 

It's probably running lean at the top end. You may need to adjust the metering rod for a slightly richer mix near WOT.

 

franklin2 -
I'm not sure what a "spark knock" sounds like...
It sounds like a mechanical knock to me. It doesn't make the noise if I just rev it up while in park. However, it sounds a little like a diesel engine sounds normally... whether in park or not.

steve83 -
Sorry... I'm not really all that mechanically inclined. Could you help me out with the terminology a little bit?

You said: "It's probably running lean at the top end."
I understand running lean means not enough fuel in the mixture. What do you mean by top end?

You said: "You may need to adjust the metering rod for a slightly richer mix near WOT."
Where is the metering rod?
What is WOT?

Sorry for the ignorance on this.. I do appreciate the help though.

Thanks,
Mike

 

 

the "top end" is high RPMs, WOT is "Wide Open Throttle".

For the transmission shifting too soon, find the vacuum line that comes off the rear of the transmission, and make sure it is hooked up to vacuum. This may have been the extra vacuum port on your carb. If this line is not hooked up, your transmission shift timing will be way off, and may not shift at all.

If you don't know much about carbs, have someone check it. I am assuming you installed the stock, or a Holley carb.

The "diesle" sound you hear is ignition knock, or "pinging". This is a symptom of a "lean condition" or igntion timing too far advanced. If yur timing was that far advanced, I would think you would have a hard time getting the engine to turn over when it is warm. If it turns over OK, I would suspect your carb running extremely lean. This could also cause a back fire through the carb at freeway speeds.

I would have someone who knows carbs richen it up and set the mixture for you. Have the igntion timing checked as well.

Hope this help.