flyboyslc1

When I bought my 1991 coupe about 5 years ago I had a mechanic put a new serp belt on it. At that time he told me he didn't care if I ever brought the car back. (Did not have an easy time with the belt replacement I guess, said something about having to lift the engine a little to get it past the crank pulley.). Well, 30000 miles later it seems that the tensioner has run out of slack and it looks like it is time for a new belt. I unleashed the tensioner, and it appears to be OK. But getting the belt off of the crank pulley is indeed difficult. I have not lifted the car and went at it from below. Is that the key? Or is there a trick or tip that someone has to get the old one off and a new one on?

Steve

Joe C

this is a new one, and maybe a first. lifting the engine to replace the belt -

install the belt on the pulley first at, or near the bottom of the crank pulley - just a little wiggle-giggle and slip the belt on the pulley. route the rest of it with the tensioner pulley last. no need to lift the car or work from underneath.

hope you've found a new mechanic....

jimmers

I would not go back to that mechanic. I made my own tool which made the job even easier to push the tensioner down.

flyboyslc1

Jimmies,

I made one of those tools myself. Made changing the alternator much easier.

flyboyslc1

Joe,

I have done almost all my own wrenching since then. Not a lot of big stuff, but just about all of it since then. In his defense, perhaps there is something a little different about my car. I did get it with over 100,000 miles on it, and do not know the history of it. I at first thought the problem was the tensioner so once I had the belt off I tried to remove it. I did notice that the tensioner bolt when I went to remove it ran into the top of the crossover frame member just a little. Seems odd that the bolt would've collided with the frame. So maybe the engine is just a little lower than usual. Don't know really. I do know that just getting the old belt out is difficult. I could just cut it I know, but want to keep it in one piece to compare it for length with the new one.

So, I will pull, tug, wiggle, whatever. Does not seem to be any trick to this. Thanks for the reply.

Steve

hcbph

I assume you have a LT1, I have a L98. I just use a breaker bar to remove the pressure the tensioner puts on the belt and starting at the a/c pulley, take it off or on and it's not been an issue.

Joe C

there is no way, on a 1991 corvette w/ a stock L98 engine that the belt tensioner, or bolt, will interfere with a crossmember. post a pic of what you've got going on there - something doesn't sound right.

another C4 thread on belt removal -

https://www.corvetteforum.com/forums...t-removal.html

Joe C

1991 corvette - L98, not an LT1 -

Hot Rod Roy

Sounds to me like it's time for new motor mounts.

flyboyslc1

Hot Rod I think you are on to something and that is kind of what I was starting to think too. The crank pulley is so close to the bottom cross member that there is not enough room to slip the belt between the crank pulley rolled edge and the cross member. I think that the motor mounts are a likely culprit. I need to look that page up in the FSM and start planning to go that way.

Don't know if there are shims along with the mount, or if the rubber just breaks down over time?

I had to leave the car at home and commute to my weeks work, so will be a while before I get back to the car to start working on it. Lucky though. Have a C5FRC to drive to work.

Thanks to all that chimed in. Yes the car has the L98. Last year before the LT1 I think it is? Glad I have it after reading all the Opti threads.

I will try to remember to post what I find.

Steve

flyboyslc1

Joe, and Hot Rod Roy too. I put the car on jack stands today and then put a small bottle jack with a wood block under the front of the oil pan. Putting just a little pressure on the engine I could see it raise about a quarter inch. that is all it took to get the belt off of the crank pulley. So it appears that I need new motor mounts. They do not look like they will be easy or fun to remove and replace.

Steve

flyboyslc1

Well, with the snow and cold associated with Iowa, I put the 1991 coupe up on jack stands and have been working at changing the motor mounts out. I would say that the FSM makes it sound easy. I have found it to be difficult work for my abilities. To make it easier to get at, I removed the exhaust manifolds, which is not easy in itself. Left side was a simple task, but the right side is involved, requiring removal of the air conditioning compressor, the compressor bracket which requires removal of a heater hose that goes through a hole in the bracket before the bracket can be removed. While this deep into it I am also replacing all heater hoses, which are many on a 1991 equipped with oil cooler option.

When I finally got down to the old mount, it was worn out for sure. Replacing both the left and right mounts in effect raised the engine about 3/8 of an inch. This corresponded to about what the mechanic told me 5 years ago. He raised the engine with the worn mounts and slid in the new belt. He didn't remember to tell me that the mounts were toast.

Here is a picture of the new and old mount side by side. So everyone can see what a 26 year old motor mount looks like. The new mount is on the left. You can see that the rubber is centered and the bolt hole is good. Compare it with the old one on the right.







Cheers.

steve
New on left, old on right<br/>

Shiptoshore

I know exactly what he's talking about it has absolutely nothing to do with the motor mounts it's the water pump pulley and the crank pulley the clearance is so tight you have to roll the water pump pulley around to try to feed it around and then at the very bottom of it it gets stuck because it's hard to get your hands up there to turn it sideways to go in between the pulleys
for whatever reason the 91 seems to be a little bit different there are tons of videos from 92s and up

flyboyslc1

I can tell you that installing new mounts raised the engine, increasing the gap between crank pulley and crossmember. That is the only place I had interference. What you have going , perhaps different.

First post? I am glad you found this forum. There is great knowledge here. Welcome!

Shiptoshore

Yes it actually is and I am loving this website this water pump pulley actually looks quite large but not aftermarket by no means the clearance between the crankshaft pulley and the water pump pulley is literally the width of the belt you actually have to roll it around to get it in between and then twist it back around I thought with it for about 45 minutes decided to continue on in the morning I would hate to think that I have to remove a pulley to get the belt on LOL