Weird vibe

[burt]

I had a breakthrough on a vibration I've had for a couple years now and am now trying to nail it down. The truck is a 1990 rc f350 reg cab 4x4 zf5 that I had a new promar rebuild put in as well as well as a moose pump bb injectors from russ. I got the turbo motor from the idit models. I chased a strange lope for a long time that I thought was part of the same problem as the vibe but changing so many things at the same time made trouble shooting harder. After much head scratching it turned out that the lope was from a malfunctioning injector. I was so pleased that it was not a defective motor I've just been running it ever since but there is an undeniable vibe that persists. The breakthrough is that I found I can recreate it subtly parked. While parked I can get it to come on a little at around 900 rpm then it smooths out till around 1900 then it comes on more obviously then persists but mellows a little at around 21 or so then seems to come on and escalate at 2500 on up. I haven't taken it much past 2600 because the vibe gets pretty bad and the tcase shifter starts making a racket clanking around. While driving it seems like I can feel the vibe acutely through the gear and tcase shifters and also in the clutch pedal. I also put a new clutch and smf in with the motor change. The flywheel being balanced wrong seems like it could do that and I wonder if it is supposed to be balanced different for the turbo motor. If any one has any ideas I'd love to hear them. Thanks to anyone who took the time to read all that as well.

 

[Oog]

Incorrect harmonic balancer

 

[burt]

Could a tired t case cause anything like this? My junkyard tcase is getting pretty sloppy too.

 

[Greg5OH]

Tcase has nothing to do with it if your parked and its vibrating.
engien mounts, transmission mounts.
Check tranny mount youd be surprised how much nicer everything is with a fresh mount.
Liek oog said, could be a failing balncer. Doubt its teh wrong one as that would give some nasty vibration, but a loose one can cause this.

 

[79jasper]

Recently a member had nearly the same thing. Was his water pump.


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[burt]

Water pump? If that turns out to be it I would have never until it failed have thought of that. Funny, just ten minutes ago I wrapped up changing the fan clutch in my other idi. I'm glad I haven't got any responses saying probably flywheel yet. Thanks for the ideas, I really want to figure this out.

 

[79jasper]

See if you can wiggle it.


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[burt]

Well it has a little play in it. Would it have none at all if it were right? This would be awesome if this fixed it

 

[79jasper]

Well it shouldn't.
Depending on how tight the belt is, may have to remove it to see how much play there really is.


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[burt]

I actually read about three quarters of that thread but then got busy and lost track of it before he got it figuered out. I also hadn't recognized that I could replicate it parked. Just been running it since it works great otherwise

 

[riotwarrior]

two things to check that harmonic as mentioned and ya could be flywheel too.

Where did flywheel come from? They are turbo engine specific FYI.

The harmonic is turbo engine specific too, I can provide a side by side image of turbo/na if need be for reference.

 

[burt]

Not sure where the flywheel came from. I had it done when I had the motor swaped. My mechanic said he had it balanced for the turbo motor locally I think. How much wiggle is normal on a water pump? There is some free play in it

 

[burt]

Water pump was replaced with the motor so I'm getting it warrantied because my mechanic agrees that it has to much play in it. It's worth a shot.

 

[Oog]

Broseph: have mechanic idle the truck with no belts on it. That way you isolate it down to engine or accessories

 

[burt]

Damn good idea. I'll do that tomorrow while I have all the belts off for the water pump. Just about to put the new pump on now. Thanks