I don't want to change the harmonic balancer for no reason if it is just the pulley, or maybe I should just replace them both just because. How long does a harmonic balancer last? Do they go bad from age?
CK5
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How to replace Harmonic Balancer on Stock 350
- Thread starter Chief Brody
- Start date
wasted wages
1 ton status
To me, it looks like the balancer ring has walked.
Another thing that can chew up belts are rusted and pitted pulley grooves.
And I agree, the fan does look like it has a wobble to it.
Another thing that can chew up belts are rusted and pitted pulley grooves.
And I agree, the fan does look like it has a wobble to it.
wasted wages
1 ton status
aftermarket pulleys are fairly cheap, I don't know if you are a dealer only kind of guy.
But I would inspect them closely while you have it apart to replace the ballancer and replace any that look worn or rusted.
But I would inspect them closely while you have it apart to replace the ballancer and replace any that look worn or rusted.
I don’t think the balancer looks like its wobbling, but the pulleys do... the elastomer looks like its pushing out a bit on the front though. could be swollen from years of oil saturation. See if you can feel the elastomer on the back side of the balancer. Is the elastomer cracked, or soft at all?
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You know me...I want OEM if I can get it, but I don't even know where you could get V-belt pulleys.
I think I will replace it just to be sure...this could be the original one from the 1975 engine for all I know
If anybody knows where you can get v-belt pulleys please post...I'll have somewhere to look in case mine are bad.
The balancer can fail after many years especially if the rubber got oil soaked as noted above,but overall its rare to see one come apart in street use,its at high rpms they'll fail most..
It would be prudent to get a new one as yours may be 30 years old.
Far as I know only some billet aluminum pulleys are about all you can get new now,or the chinsy Mr.Gasket chrome ones--you may find repops or NOS ones on various websites that specialize in old muscle cars though,but they will be expensive ..if yours are warped then they will need replacing,but if they are just a bit rusty they could be glass beaded--one that is warped or pinched will wear the belt thinner in spots and end up making noises..
In my previous post about installing the balancer the way I worded it,it came out sounding like I recommended using the wood block & hammer method,but I was trying to say using the installer tool is the correct way to do it...but back in the 60's the hammer and wood was the only way to do it since the crank snout was not drilled and tapped for a bolt yet,I think 1968 was when they started doing that..
It would be prudent to get a new one as yours may be 30 years old.
Far as I know only some billet aluminum pulleys are about all you can get new now,or the chinsy Mr.Gasket chrome ones--you may find repops or NOS ones on various websites that specialize in old muscle cars though,but they will be expensive ..if yours are warped then they will need replacing,but if they are just a bit rusty they could be glass beaded--one that is warped or pinched will wear the belt thinner in spots and end up making noises..
In my previous post about installing the balancer the way I worded it,it came out sounding like I recommended using the wood block & hammer method,but I was trying to say using the installer tool is the correct way to do it...but back in the 60's the hammer and wood was the only way to do it since the crank snout was not drilled and tapped for a bolt yet,I think 1968 was when they started doing that..
When looking for crank shaft pulley they ask "long water pump or short"
Nevermind, Summit had the answer
Nevermind, Summit had the answer
wasted wages
1 ton status
wasted wages
1 ton status
wasted wages
1 ton status
I've seen people tighten belts to the point of bending pulleys...
one night a guy I worked with called me and said he put new belts on a K5 he just bought for his son to drive to school. He took it for a test drive and said, now when he started it, it didn't sound right...
I drove over to his house and he cranked it up and the motor started knocking like hell!!!
It was a SBC 400, and he had tightened the belts so tight, it broke the #1 counterweight on the crankshaft from the leverage... it had broken the crank in such a way that the two pieces of counterweight would still turn the timing chain..but it would knock like a SOB..
one night a guy I worked with called me and said he put new belts on a K5 he just bought for his son to drive to school. He took it for a test drive and said, now when he started it, it didn't sound right...
I drove over to his house and he cranked it up and the motor started knocking like hell!!!
It was a SBC 400, and he had tightened the belts so tight, it broke the #1 counterweight on the crankshaft from the leverage... it had broken the crank in such a way that the two pieces of counterweight would still turn the timing chain..but it would knock like a SOB..
that triple groove looks like the one. Now I need to find to right damper
https://www.summitracing.com/parts/ado-10243271/make/chevrolet
ACDelco GM OE Harmonic Balancers 10243271 When I run that one every where else but Summit, it says it does not fit my application
ACDelco GM OE Harmonic Balancers 10243271 When I run that one every where else but Summit, it says it does not fit my application
You are correct My boo boo
I can't believe they don't have one that does fit not sure why that one doesn't
Is your engine original to the truck?..
You mentioned the balancer is 8" diameter--most I've seen that big were used on earlier 350's with 4 bolt mains...might be a good idea to look at the engine code and look it up to positively ID the year and CID..
You mentioned the balancer is 8" diameter--most I've seen that big were used on earlier 350's with 4 bolt mains...might be a good idea to look at the engine code and look it up to positively ID the year and CID..
