vibration at start up

[RKTINC]

I have had a couple FJ80's and several 100's but this is my first FZJ and notice a mild vibration at start up.

It is a very clean, rust free 277k mile 1997 FZJ80. Truck runs great, idles very quietly (compared to my 3FE) and drives very well with a tad bit of wonder at highway speeds which I will try to cure with a lift, tires, and alignment. Only thing that is odd is a noticeable start up vibration while cranking and initial fire. It this a motor mount issue? Is it normal? Is it a sign of a worn out engine? Only thing that I can compare it to is how my newer John Deere 4 Cyl diesel tractors start up. Very tractor-like, subtle vibration then instantly smooths out at idle.

I have not read about engine mount issues on here and the search functions defaults to V8 swaps when I search.

Thoughts?

 

[bhsdriller]

Common if this is what you're referencing. Search "fzj80 start up rattle" and you'll get lots of threads

start up rattle?

forum.ih8mud.com

 

[LandLocked93]

I have had a couple FJ80's and several 100's but this is my first FZJ and notice a mild vibration at start up.

It is a very clean, rust free 277k mile 1997 FZJ80. Truck runs great, idles very quietly (compared to my 3FE) and drives very well with a tad bit of wonder at highway speeds which I will try to cure with a lift, tires, and alignment. Only thing that is odd is a noticeable start up vibration while cranking and initial fire. It this a motor mount issue? Is it normal? Is it a sign of a worn out engine? Only thing that I can compare it to is how my newer John Deere 4 Cyl diesel tractors start up. Very tractor-like, subtle vibration then instantly smooths out at idle.

I have not read about engine mount issues on here and the search functions defaults to V8 swaps when I search.

Thoughts?

Can't say it's normal.
Can say mine has always done that and I know my mounts are good.
Not sure what the above video shows. Just going by your description of the "issue".

edit: "...a tad bit of wonder at highway speeds which I will try to cure with a lift..." Let us know how that goes.

 

[cvenom96]

Dunno if it's the rattle everyone talks about but mine would rattle at startup due to the the exhause contacting the frame where it crosses over between the muffler and resonator. It sat too low in the mount for some reason.

 

[RKTINC]

Can't say it's normal.
Can say mine has always done that and I know my mounts are good.
Not sure what the above video shows. Just going by your description of the "issue".

edit: "...a tad bit of wonder at highway speeds which I will try to cure with a lift..." Let us know how that goes.

Yea, it is very subtle but I am used to a low mile 100 with 285's on it. With this 80 being untouched in 277k miles, I am probably headed towards steering box work, wheel bearings, tie rod ends in my future

 

[RKTINC]

Dunno if it's the rattle everyone talks about but mine would rattle at startup due to the the exhause contacting the frame where it crosses over between the muffler and resonator. It sat too low in the mount for some reason.

That could the an issue. I will put that on my list. Exhaust is on the other side of the FZJ vs my FJ80 so It may be something I need to listen for.

 

[Kernal]

The rubber of the hanger blocks for the exhaust system crack with age and when that happens, IME, you can get a rattle/rumble on start up or when crossing a rough surface (railroad tracks) or when idling in gear, foot on brake pedal. You can check your exhaust system hangers (cold engine) by getting under the vehicle and pushing up on the pipes while watching the hanger blocks for movement.

 

[COYS]

I'm chasing a rattle at hwy speeds, but came across this while I was under the truck. I'm not sure if it's what's causing the hwy buzz/rattle noise, but mine has def tapped out at 24yrs/282K. I'm sure I've been running it like this for quite some time now.

Should look like this