tapping under load

[69er]

Nope. Torque converter maybe?

 

[1985 Ford F-150]

No I dont think so. Is it 2wd or 4wd?

 

[m78]

I went back and reread the OP.
Find the steapest hill you can and park on it to see if it's a gravity thing.

 

[69er]

It's a 2 wheel drive Dan.

I don't follow you with the gravity thing Mark. Could you explain it a little please. No shortage of steep hills here.

 

[john112deere]

I think what Mark is saying is that since you're experiencing the problem when climbing hills but not revving in Park, maybe the issue has to do with something moving when the truck is pointed up a steep hill.

 

[69er]

OK, thanks Ian. I will try it although it will do it on a fairly level surface also. It seems to be affected by being under load like acceleration. Today I noticed it wasn't consistent but is there much more often than not. I did pull the cover from the flywheel yesterday looking for any obvious marks or damage and didn't notice anything unusual.

 

[1985 Ford F-150]

Is it a tap or kind of a clunk like a u joint or carrier bearing would make?

 

[69er]

Best I could describe it is something getting into the fan. Like it was ticking something lightly then moving away from it, but there is nothing even remotely close to it.

 

[1985 Ford F-150]

Had one more idea on my old 352 the dipstick would hit the crank and make a tickin sound that bugged the hell outta me till I pulled out the dip stick and saw it was all buggered up. Check yours for any damage. If its been doin it for very long it wont be hard to tell if its been hittin or not.

 

[69er]

Thanks Dan, I'd heard of that before but had forgotten it. That isn't it here though. It just started after putting in a new starter. From in the cab it sounds like it's down there too but can't really tell. I'll yank it tomorrow but don't expect to find anything.

The dipstick story reminds me of when I installed a 390 crank in a 360 motor except mine was probably noisier.

 

[1985 Ford F-150]

Ya dont happen to have a video camera do ya?

 

[69er]

No, I read about someone else doing that and thought it was a great idea. I'll ask a buddy tomorrow. He may have one I could use.

 

[1985 Ford F-150]

Thatd make it alot easier to see and hear whats goin on. That way we can get a better idea of whats goin on.

 

[69er]

I'll see what I can do then. Thanks a lot for your time Dan. I'm off to bed now. Getting late. I appreciate everyone's input here and hope I can help some others in the future.

 

[TexasNomad]

I wonder maybe if his drive shaft is getting a little wobble in it under load??

 

[1985 Ford F-150]

Yep no problem thats what were here for.

 

[69er]

Just got back to it today for a bit. I pulled the starter and the gear has had a little chewed off the end where it meets the ring gear. Also can see some metal in the opening for the starter. Apparently somehow the two are meeting when it's under load. I have cranked the motor around using a block of wood to check if the ring gear was warped before and it showed to be true. Saw no loose nuts either. I don't get it but am 99.9% certain that's where the noise is coming from.

 

[1985 Ford F-150]

Yeah that would definitly make a noise but the only thing I can think of that would do that is the starter itself bein loose and chewin up the gears. I just pulled the starter off my 72 and its been loose and it chewed up the ring gear and the starter gear. Ive had to tighten it once so I think they have a tendancy to shake loose again over time unless ya crank em down. Try puttin it back in and get some grade 8 bolts that are the same size then tighten it down as tight as ya can.

 

[69er]

You were close Dan. I'd checked the starter at the first and it was tight. The only thing a neighbor and I could figure was that the Bendix was slipping into the gear under acceleration. It didn't feel loose but couldn't do it any other way. I took the starter in and replaced it. Before installing the new one I looked at the Bendix on it and it was flopping around loose. The parts store had one more so I went back to town and got it. That one was good and fixed the problem. I had problems with starters for the truck quite a few years ago but those had a different problem. Hopefully this will save someone else the aggravation I had this time. Thanks again for all the helpful suggestions. I plan to be around to help someone with their situation if I have any useful suggestions.

 

[m78]

Glad to see you found the problem. That bendix is one of he things I thought might show up if you parked on a hill for gravity check.