Posted on here last night but haven't gotten any replies. I have a 66 f100 straight 6 240 3 speed.( I have pictures of it in an album if you want to see it and let me know what you think of the way it looks.) it runs and drives alright I drive it everyday it never brakes down or stalls out but vibrates the whole truck when it's just idling. It only does it when it's idling but not when I accelerate or rev it up. If anyone knows if this can be a easy fix let me know I would appreciate it.

 

Do a engine compression test, and post the results.

 

Could take a video since its at idle and post link. Make easier for some the guys troubleshoot

 

Sounds like a dead cylinder need to ck each for spark at idle ground each plug wire the good ones will make it run worse the bad one will have no difference

 

That is one great looking truck!!!
First and Foremost, Welcome to the Family of Ford Truck Enthusiast!!.

Taking a shot in the dark I can come up with a couple of possible causes for vibration?? . Suggest start with the least labor intensive by checking for 'pulley' and 'belt' alignment, and belt tension. Have any of the pulleys, or harmonic balancer been replaced?? Check the U joints for wear, or looseness. I have had U joints vibrate at low RPM due to wear and once the RPM picks up the noise goes way. Is there a vibration at idle with the clutch pedal depressed?

As fordpt mentioned, may then need to move onto the engine. Rather than going thru a long testimonial, and doubts in using a hose, non-garden type, in troubleshooting an engine, suggest giving it a try while able to start and run the engine, with any luck isolate the source. Suggest focus on the valve cover/rocker arm assembly. If doing compression, remove all the plugs; checking the condition and location, prop the throttle plate fully open. Found a cheap tools that work great for me 1) start button, has 2 leads, one to the start pin on the start relay, and the other to the pos. side of batt. I can now watch, and make any adjustments while under the hood.

Again, welcome to FTE; looking forward to your input and suggestions!!

 

I don't hear you describing an engine malfunction. Have you checked the motor mounts, transmission mount, and cab mounts for deterioration and/or correctness? At what rpm is your engine idle set? Perhaps kick it up a couple of hundred rpms?

 

Thanks for all the input. Started to look at all the mounts everywhere and one of the bolts on the motor mount is broke off and the stud is stuck in in the engine. Anyone have an idea of how much this would cost to fix? I'm pretty sure it's the problem.

 

Interested in other member's input and/or suggestions!!

Seem to recall similar/same engine mount is used for all the year appropriate engines block. My 65 has 2 bolt holes where bolts are used to secure the mount to the engine. The other end of the mount, on my 65, has a single threaded stud that slides into a slot in the engine perch where a nut is used to secure the engine mount to the engine perch. I would first determine if it can be repaired w/out removing the engine. Remove the tire on effected side and make sure the truck is secure and stable. My experience has been, in order to remove the engine mount, I had to lift the engine just enough for the treads on the engine mount to clear. In order to do this, need to remove the nuts and bolts that secure the mount to block and perch on the effected side. With the other engine mount just remove the nut/bolt that secures the mount to the engine perch, this way should be able to lift the engine slightly w/out binding. I have used a floor jack with a pad to slightly lift the engine, or an engine lift/picker from the top, once the mount is removed on the effected side should be able to determine if the repair can be made. If it's a bolt that has sheared then it's a matter of determine if there's sufficient clearance for appropriate size drill bit to use an easy out. Suggest using a wooden block, or something similar, for safety and support once the engine mount has been removed. If decide to have it done by shop, re-install the effected mount, lower the engine with mount onto the perch, secure the mounts to the perch on both sides and drive truck to trusted shop.

 

I also realized it was leaking oil from the right side and seems to be coming from 4 holes on the block. It looks like there was bolts in there at some point or that something should be bolted on. I put an album up of the pictures of where the problem seems to be let me know of anyone knows what's supposed to be there

 

Turns out its 4 dead cylinders. Check out my new post it's under dead cylinders? Maybe you can help me out with what it could be because it doesn't seem to be the spark plugs or plug wires.

 

Getting a broken bolt out of the engine block can be really easy or really hard. If the bolt is broken off because it bottomed in the hole and someone turned on it until it broke then it will be difficult to remove. If on the other hand it just broke and there are some remains of the bolt available to clamp on a vice grip you may be able to simply unscrew it. Or put a nut on the stud and weld the nut to the stud and then unscrew it. If it is broke off level with the block, removal will involve drilling a hole in the bolt, installing a "easy out" and unscrewing the broken bolt. This fix is often best left to professionals and done with the engine out. Or you could just ignore it as long as the rest of the mount bolts are snug and the mount is in good shape. IMHO.