Vibration/shudder from engine
 

Under load, like going up a hill or just plain accelerating, I feel a vibrate/shudder coming from engine. I can also feel it in park when I give it gas. No matter how fast going down the road, if foot is off the gas it is very smooth. It is also smooth at idle.

I'm stumped! Plugs and wires were changed when I had valve seals done back in Sept. Could it still be a bad plug or firing order, I guess I would have noticed before then? Maybe a plug got bad since? Timing, hoses??

I'm stumped! Thanks for all help.

Re: Vibration/shudder from engine
 

Did the row of black widow bikes you knocked over damage the harmonic balancer? Did Clyde check the accelerator pump? That is all I have, sorry.

Re: Vibration/shudder from engine
 

How are the condition of the motor mounts?

Re: Vibration/shudder from engine
 

Check your plugs. They should all look similar. If one or more are different, those are your suspect cylinders. Did you replace the cap with the wires? Could be the cap, rotor or the button in the cap.

An almost plugged fuel filter will cause cutouts under load.

To eliminate accessories, remove all the belts and do a brief retest in park. If the vibration goes away, one of the accessories is suspect. Keep in mind, no belts, no water flow so keep the tests under a few minutes.

Re: Vibration/shudder from engine
 

I will start with the plugs, and try it without belts. We did replace cap and wires. Thanks.

Oh, i bet the black widows messed with it! Lol, any which way but loose!

Re: Vibration/shudder from engine
 

Did you do a compression test. You may have a low cylinder. Did it start to miss after you did the plugs. You may have a bad wire that got damaged when you pulled them off the plugs. Did you check the wires with an ohmmeter.

Re: Vibration/shudder from engine
 

Well here is what happned, i checked plugs and all were clean, so i wire brushed anyway. Then ran engine without fan belt, it seemed still shuttery NOT hesitating or skipping, then when i put the belt back on i took for a test drive and seemed pretty smooth. Now i'm more confused!!!

I guess time will tell on this one.

Oh, and it was the same when i checked after cleaning the plugs.

Re: Vibration/shudder from engine
 

Check your fuel filter, maybe it's not getting the fuel it needs at high RPM. Air cleaner nice and clean? What about your plug wires? and engine mounts ok? Hmmm.. what's the story behind the black widow bikes? Or am I missing the joke lol

Re: Vibration/shudder from engine
 

The black widow thing is the gang in the two clint eastwood movies, "anyway which way but loose" and "any which way you can". Philo beddoe was clints character.

Plugs are good, wires are good. Will check fuel filtr, but i dont think thats it. It does not skip or hesitate at all.

Question, should the harmonic balancer be "pin" straight? I can see a little movement in mine.

Re: Vibration/shudder from engine
 

This thread has several obscure things that might be worth checking.

http://www.jalopyjournal.com/forum/t...ration.836151/

Re: Vibration/shudder from engine
 

Yeah, that's a good thread, I have a good mechanic taking a look at it, a lot is pointing to the h. balancer. Will certainly post results.