PDA

View Full Version : New motor mounts today.



sailun
03-08-2007, 20:31
Vibration through the vehicle, and motor was really shakin when shutting it off, so...........

the Burb received new motor mounts today. Sure could not have done this in my garage.

Truck up on the lift, jack under the motor, jack under the rear bumper, so we don't get jacked off the lift, one guy under the vehicle, one guy on a ladder going in the wheel well.

About 1.5 hours, drive in, drive out. The man on the ladder was only needed about 5 minutes per side.

Vibration feels worse than ever, but it sure damps the shake when I shut off the mill.

Probably feel better when they break in a little.

chickenhunterbob
03-09-2007, 09:34
What is the reason you say that you could not have done this in your garage?

I was planning on changing mine this weekend, in my garage.

Been thinking about it for quite a while, I think I can do it.

Where did they jack under the engine?

The GM manual strongly scolds me for even thinking about jacking under the oil pan, but at this point that is my intention.

I was figuring on just using a piece of 2x4 between the jack and the pan.

Anybody else have any engine lifting jacking advise?

sailun
03-09-2007, 14:42
I'm not an experienced mechanic, but I can usually struggle through the easy stuff. But this was 10 times easier on a lift, rather than on the floor, and I could not have done it without an experienced helper..

And the floor's been really cold this past week !

Well, a helper is really gonna make your life easier. Sometimes, a third to hold the light would be OK, too.

One guy would attack from the front after removing bash plates. Used an air ratchet, with a 2-foot extension on it to get front side of the thru-bolt. Helper would hold the nut in back, either from the bottom, or thru the wheel well. Also, when R&R'g mounts to frame, it's tough to reach both bolt and nut at the same time, especially on drivers side, where frt diff is in the way.

And there sure aint much room for swinging those wrenches, once you get them on the nuts. Especially the bottom of the mount.

You won't need to worry about your torque wrench or torque values, cuz there's no room for it.

Yeah, "don't jack using the oil pan, or harmonic balancer". That leaves exactly nothing. We used a 2x4 against the oil pan.

My buddy mentioned the importance of jacking the motor securely. Your hands will be in there, so do it right. We used a large screw jack, not a hydraulic jack. Lot's more control lowering the motor and lining up the holes.

Use your giant pry bar to shift the engine around, to line up the holes.

Only needed about 2 inches of lift to wiggle the motor mounts out.

By the way, Alldata said to remove the lower control arms. We did not. There's absolutely no reason to, at least not on a '97 Burb.

The mounts we used were integral units, steel mount and rubber bumper all in one, not just the replacing the rubbers, like on KD's web site.

I think we cranked my thru-bolts too tight, and that's why I'm getting stronger vibration.

Work safe.

john8662
03-09-2007, 15:41
Vibration or Shaking?

Shaking, you've got a running issue with the engine, an injector not firing correctly, a worn out injection pump, air in the fuel system, etc. etc.

Some shudder or vibration is normal, especially a diesel. The electronic 6.5's are fairly well-mannered in regard to idle quality.

Vibration issues could be other mounts, like the transmission or transfercase mounts for example, or something else on the engine making contact with the cab or frame, like exhaust.

Yes, changing the mounts on one of these rigs looks like a MAJOR pita, I only did it with the engine out and it was hard enough to get my wrenches in there, don't wanna do it in chassis, been there done that on my '86, not again..

As far as lifting the engine, I chose to use an engine hoist and use the lift points on the engine, just worked around the hoist feet underneath on my back. If you did it lifting the engine underneath, I like the idea of the pan rails for support. You might also get away with a 1 foot piece square of 2x12, then using the jack. I set engines on the floor all the time on their pan. But, they're not supporting a transmission and components either...

J

sailun
03-12-2007, 04:49
Vibrates while idling, really shakes when I shut it off. I was hoping the new motor mounts would eliminate the vibration. Made it worse. Haven't checked for anything else contacting the frame, the exhaust had plenty of room when I put it in.

Probly put new injectors in this weekend. At 162k, they're probly ready.

mrdueck
03-12-2007, 11:03
I've been considering doing mine as well. I have about 130 000 miles on mine and when the engine is warm it gives a really annoying rumble that shakes your ear drums appart. I haven't installed my subwoofer yet since purchasing this thing in fall and don't think I will as this rumble would drown it out (I'm mostly having fun with this comment). It is driving my wife nuts though. When the motor is cold and idles at 800+, no noise, just when it drops to around 700 according to the dash tach. Any thoughts?

Hay chickenhunterbob, maybe we should swap some labour here since it sounds like we are close to each other. Let me know if you haven't done yours yet.