Causes for Chevy 454 belt failure

[DaveVA78Chieftain]

From what I have seen on the net over the years is belt failure is a common problem w/454's.  Best information I have seen is:
It is usually due to a bearing straining or complete bearing seizure. This causes pulley wobble, seizure and/or misalignment, either throwing or breaking your belts. Some bearings don't restrain or seize until they are warmed up or hot, so they are hard to identify. Most of the time it's the water pump pulley bearing. If your water pump has over 40K miles, replace it w/OEM.  This could be an air pump, water pump, or ac compressor problem.  Fan clutch can go out and take the water pump with it.
I have included a front pic of an  '89, 454 showing fan belt routing if someone needs it for reference.

Dave

[jimbo16720]

 It's seems to be a common problem with 454's. It's also easy to see why they would squeal. The belts don't cover enough area on some of the pulleys. The one around the alt to waterpump and crank only covers about 20 degrees of the water pump.

[Lash61]

Ive found that if I install GATES belts all my problems go away. If you look closely most other on the shelf belts are thin and the angle of the V on these belts does not match the pully V so they wedge in and wear very quickly. The GATES belts on the other hand match the pully and sit at the bottom of the pully. Also screaming belts are caused by not enough tension.

[ClydesdaleKevin]

Yep, that is what our belts look like, which as luck would have it we just replaced with Gates belts...all 5 of them!

Some of the belts go into a groove on the same pulley other belts go to.  One is a serpentine belt.

In Dave's picture, there is a missing belt.  Right below the alternator you can see another pulley...which is a secondary air pump.  The belt is missing in the photo...could have been taken off because maybe the air pump went bad and seized.

By the way, apparently the air pump does more for your engine than just being an emissions control.  It helps with the air fuel mixture atomization, and even improves performance and fuel economy.  There are 2 fat hoses that blow pretty high pressure air right into your air cleaner housing as part of the process, so you can see how that would be beneficial.

That said, replacement air pumps used to be crazy expensive, which is why folks would take them off or disable them, because the small gain it gives wasn't worth the high cost of replacing the pump/pumps.  Now replacements are available for around 60-70 bucks.  I intend to keep my AIR system working.

Kev

[ClydesdaleKevin]

Okay guys...on the one hand, luck is with me and my power steering pump is fine...on the other hand, I was once again shafted by my AZ mechanics!   

There appear to be three belts leading to the power steering pump pulley.  Two are loose, and the third has slipped from the pulley and is all mangled and chewed up, laying loose near the bottom crank pulley.  I'll have to remove the belt in the morning to take it with me to get the right belts, which looks like I'll have to take every bloody belt off the engine just to get it off.

I can see the belts in Dave's picture above, but the image isn't clear enough to make out the exact routing...in other word, which belt goes over which pulley and in which groove.  Anyone have a diagram or drawing of the belt routing for an 1989 454 in a P30 chassis?

Thanks ahead of time guys!

Kev

[ClydesdaleKevin]

Also, anyone have any helpful tips for replacing and tightening the belts with the radiator still in place?  I really don't want to have to remove the radiator, and it sure is tight in there with the radiator in the way!

Kev

[DaveVA78Chieftain]

Refer to page A-2 (pdf page 217) of the Chevy Motorhome Chassis Service Guide that is downloadable from the Free Manuals section for belt routing and information.   THat includes OEM P/N that can be easily crossed to aftermarket P/N.

Dave

[DonD]

"In Dave's picture, there is a missing belt.  Right below the alternator you can see another pulley...which is a secondary air pump.  The belt is missing in the photo...could have been taken off because maybe the air pump went bad and seized." That belt drives the second pump AND the Alt so it really isn't missing, just a bit short  W%
I want to replace all my belts soon, just need the incentive to pull the rad or whatever it takes.

[tiinytina]

We removed the AIR system completely. all belts resized appropriately...  it didnt' change mileage or power.. then again we put on BANKS at the same time....  ours has RAM air intake in nose, front passenger side of radiator.

Kev - if you need.. I can get under Gone and phone you on what belt goes where.. granted no AIR system... assuming a 1987 is similar/identical to a 1989...  no clue what brand belts my mechanic friend put on her.. but needless to say I am going to check all this or next week .... All were replaced last summer. One came loose off the hydroboost after a 2 hr run in hot weather... nice to hit the brakes and ... eeeks.... wrench took care of it....

Tina

[DaveVA78Chieftain]

OK, I will be nice guy.  Here is the 1985 and Later P30 454 belt diagram.



http://i286.photobucket.com/albums/ll120/BaileyDave/Chevy%20P30/1985andLaterP30Belts.gif

[ClydesdaleKevin]

Thanks guys!  And thank you Dave!  I downloaded the manual and looked closely at the diagrams, and it appears that there are only supposed to be 2 belts going to the power steering pump, but I'll crawl under the RV again before I go to the auto parts store.  It just might be very possible that the mechanic left an old belt just laying there wrapped around the lower pulley...or it might go to another pulley...or I might be reading the diagram and manual wrong and it might be a third belt.  I guess the easiest way for me to check would be to count the grooves in the pulley on the power steering pump...lol!  I'll let everyone know what I find out this evening after I have fixed everything.

Kev

[DonD]

Thanks guys!  And thank you Dave!  I downloaded the manual and looked closely at the diagrams, and it appears that there are only supposed to be 2 belts going to the power steering pump, but I'll crawl under the RV again before I go to the auto parts store.  It just might be very possible that the mechanic left an old belt just laying there wrapped around the lower pulley...or it might go to another pulley...or I might be reading the diagram and manual wrong and it might be a third belt*.  I guess the easiest way for me to check would be to count the grooves in the pulley on the power steering pump...lol!  I'll let everyone know what I find out this evening after I have fixed everything.

Kev

*Mine has 3 EDIT 4!, not sure what goes to what...yet.

[DonD]

[DonD]

[ClydesdaleKevin]

Thanks Don!  That last diagram was the icing on the cake!  Ours is the lower right hand set up, with A/C and two air pumps.

No wonder the power steering was out unless it was at high idle or higher RPMs!  Its the inside primary drive belt for the power steering that is off the pulley and mangled...so the middle belt, which goes to the AC, is the only belt turning the power steering pulley, which its not designed for, being a very long skinny belt that really only uses the power steering pulley as an idler pulley.  The outer belt is of course for the upper AIR pump, which drives off of the main belt for the power steering.

As my crappy luck would have it, it is indeed the innermost belt, which means I have to remove EVERY other belt to replace it...

Hey, at least I have the diagrams now, thanks to Don and Dave!  Its going to be a project, but not an impossible one.

So, off to the auto parts store!

Kev

[DonD]

Thanks Don!  That last diagram was the icing on the cake!  Ours is the lower right hand set up, with A/C and two air pumps.
With your PS compromised you must not have much boosted braking at those low RPMs ?

[TommyM]

Okay guys...on the one hand, luck is with me and my power steering pump is fine...on the other hand, I was once again shafted by my AZ mechanics!   

Ouch for your mechanics!  That seems a bit harsh, unless you left out some details that would indicate this was the mechanic's fault.  Sometimes when you drive a 20+ year-old, 10,000+lb vehicle half-way across the continent, "stuff" happens, don't you think?  I know when I work on things, no matter how careful, thorough, and diligent I am, sometimes something goes wrong. 

Having said that, as you're changing out your belts, keep an eye out for worn bearings, wobbly or misaligned pulleys, bolts loose or missing from brackets, or anything else that could contribute to premature belt failure. 

Recently, my wife drove my pickup, and mentioned that for a few minutes there was a grinding noise coming from the engine, that then went away and didn't return.  When she got home, I popped the hood, and two bolts were missing from the power steering pump bracket, the pump had gotten caddywompus, and the pulley grinded a groove in another nearby bracket.  Strangely, all that happened without throwing the belts!  So you never know. . .

Tommy

[ClydesdaleKevin]

Its a long sad story about the mechanics I used to use in Arizona.  If you read my threads about travel from Arizona and Oklahoma and even Kentucky, you'll realize I'm being more than fair with those incompetent idiots.

That said, I found out exactly why it threw and chewed the belt, even though it had never damaged belts before they touched it.  I mean really, I'm not a mechanic, but I didn't find it all that hard to change out the belts and tighten them...but when installing that belt, I saw that the mechanic had damaged the pulley by prying on it to tighten the pump...why he pried it there, I'll never know!  Its easy to get a pry bar in from the top, and tighten the nut!  Anyhow, he gouged it and bent it inward...fortunately I was able to get my smallest pair of vice grips on the pulley and bend it back outward, and a little emery cloth smoothed it out.  Another thing the incompetent idiot did was use too long a belt!  I matched up the belt to the one that came off, and it was too long, and couldn't be tightened all the way on the tightest setting...back to the auto store I went, got a belt an inch shorter, and it was a perfect fit.  Incidently, the belt the manual and the auto store computers call for is a good two inches longer than the belt my former mechanics installed, so OEM would have been way too long!

The other belts were easy to reinstall and tighten, and now all my belts are back in order, the power steering is working perfectly again, and the belt tightness is perfect after running the engine for 20 minutes (had to let the trans fluid warm up to check the level after the filter and fluid change anyway.)

It wasn't all that bad a job after all!  Even the power steering pump tightening process, which was the most difficult, wasn't all that hard to do from above.  In fact, most of the work was from inside the house, except fixing the pulley, and getting the lower belts lined up in the grooves before tightening them.

Success!!!

Kev

[DaveVA78Chieftain]

Congrats.  To top it all off this thread has a lot of useful information to boot!   

Dave

[DonD]

I see the adj on the top A.I.R., the alt..the PS pump..where else?   i??

[Elandan2]

For future reference, you may find a square hole in the power steering pump bracket.  You can put a rachet wrench in the hole and use that to tighten the belt.  It's there to prevent prying on the pump body (or pulley!)  Rick

[ClydesdaleKevin]

There is an adjustment bolt for the power steering pump on the inboard side of the pump, and the pivot bolt for it is reachable under the RV.  This is the first belt to go on...use a pry bar from above under the pivot bolt, and rock it back against the water pump housing, then tighten the adjustment bolt, and go back under and tighten the pivot bolt.  On ours, the adjustment bolt was 5/8, and the pivot bolt was 15mm of all things.

The adjustment bolt for the air conditioning compressor is easier, and this is the second belt to go on.  The pivot bolt for the air is on the bottom left corner of the ac compressor, looking at if from the back.  The adjustment bolt is on the top right corner, and has a tensioner built in, so you don't have to pry it against anything, just loosen the big bolt, and get a 7/16 socket on the tensioner bolt and crank it down until the belt is tight, then tighten the big bolt and the pivot bolts, both 9/16.

The adjustment bolt for the top AIR pump is 1/2 inch, located on the right side of the pump, and the 1/2 pivot bolt is located on the left side of the pump.  You can use a pry bar against the metal bracket to the right of the pump, but I used a piece of wood on top of that bracket to raise the pivot point and keep the pry bar from sliding while tightening the bolts.  This is the third belt to go on.

The adjustment bolt on the alternator, also 1/2 inch, is located on the left side of the alternator, and the pivot bolt is located on the front bottom right.  This is the last belt to go on.  You can pry against the same bracket, through the hole, that you tightened the AIR pump with.  Once you get the adjustment bolt tightened, you'll have to tighten the 1/2 inch pivot bolt with a box wrench, since the belt goes in front of it and you won't be able to get a socket on it.

All in all not a very difficult job at all, and I could probably change out all the belts the next time in less than an hour.

Kev

[ClydesdaleKevin]

Good to know, Rick!  I was wondering what that square hole was for!  Although I found it just as easy to use my long pry bar from above, with the end under the bracket where the adjustment bolt is, and using the water pump body as a pivot point...there is plenty of room to work the pry bar from this angle and you're not putting that much pressure on the water pump.  I guess it would be just as easy to use a long breaker bar in that square hole, but the pry bar does the trick as well from above.

Kev

[DonD]

Thank You!!

[ClydesdaleKevin]

Just take a look above, Ken...a whole bunch of diagrams and pictures of the belts and how they go.

Kev