305 tpi bad harmonic balancer
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Car: 86 Trans Am
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305 tpi bad harmonic balancer
On my 86 ta 305 tpi my engine just started rattling during rpms. Oil is full and oil pressure is very good. But just a loud rattle? All belts and pulls look good. Maybe a bad bearing?
120k
Edit shop found it was the harmonic balancer that was knocking
120k
Edit shop found it was the harmonic balancer that was knocking
Last edited by apie2546; 09-21-2014 at 10:39 AM.
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Re: 305 tpi rattle
Also I'd like to note I just filled it with middle gas out here less than 2 miles ago. Will try new gas. Sounds almost like detonation
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Re: 305 tpi rattle
Good news! Shop called me and said the timing chain was bad causing the knocking. Whew. There goes the new engine scare
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Re: 305 tpi bad harmonic balancer
So it turned out to be a broken harmonic balancer the shop showed me (from a bad burnout I think) and so they are replacing it this weekend. Does anyone know approximately how much it costs at 90 an hour for labor and new part
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Re: 305 tpi bad harmonic balancer
$90 per hour !!! what a rip off. you could have fixed it yourself and saved the money.
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Re: 305 tpi bad harmonic balancer
Unfortunately. Cheapest shop in town. I live in nowhere took it to them because it really sounded like engine knock
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Re: 305 tpi bad harmonic balancer
Well it is back from the shop. 2 year warranty on part & workmanship for $318
Not too bad
Not too bad
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Re: 305 tpi bad harmonic balancer
$80-$90 an hour is pretty much the going rate these days. $318 for labor, a new damper, timing set and gaskets seems more than reasonable to me.
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Re: 305 tpi bad harmonic balancer
$80-$90 an hour is pretty much the going rate these days.
Kinda like brain surgery: ya wanna get that done by the low bidder??
I also agree with the comment on the total bill; looks entirely reasonable to me. 2 hrs labor plus parts, not a bad deal at all.
Which is not the same as saying, you couldn't do it for less; only, if you're going to attempt to daily-drive an ANTIQQQUE CAR, and PAY SOMEBODY ELSE to keep it up for ya, might wanna start researching more lucrative careers than whatever yer doin right now.
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Re: 305 tpi bad harmonic balancer
Kinda like brain surgery: ya wanna get that done by the low bidder??
I also agree with the comment on the total bill; looks entirely reasonable to me. 2 hrs labor plus parts, not a bad deal at all.
Which is not the same as saying, you couldn't do it for less; only, if you're going to attempt to daily-drive an ANTIQQQUE CAR, and PAY SOMEBODY ELSE to keep it up for ya, might wanna start researching more lucrative careers than whatever yer doin right now.
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Re: 305 tpi bad harmonic balancer
I'm not so sure he did get the timing set , gaskets , and damper for that price , How bout it apie2546 , did the do the timing chain and gears as well as the damper , or did they just do the damper for the $318 ? I notice your post I quoted below says "2 year warranty on part" and not "partS" , and that's why I'm askin what , exactly , got replaced ?
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Re: 305 tpi bad harmonic balancer
On the labor quote it states the timing chain gaskets damper and harmonic balancer. I don't believe they warranty timing chains for some reason. Or gaskets.
Usually I do most repairs. But the engine knock generally freaked me out so I took it in to have someone else tell me the engine was done. Luckily it wasn't lol. I always save my FD checks in case of a rainy day.
Usually I do most repairs. But the engine knock generally freaked me out so I took it in to have someone else tell me the engine was done. Luckily it wasn't lol. I always save my FD checks in case of a rainy day.
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Re: 305 tpi bad harmonic balancer
Yeah that punctuation and capitalization can kill ya...
Kinda like, "I helped my brother Jack off his horse"
Kinda like, "I helped my brother Jack off his horse"
#20
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Re: 305 tpi bad harmonic balancer
Ive seen too many OE dampers where the inertia ring was walking its way off the elastomer. A couple that were about to cut into the oil cooler lines. That's why I prefer either a one piece fluid damper or the SFI type with snap rings keeping the pieces together.
#22
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Re: 305 tpi bad harmonic balancer
BTW, The tech that did that repair job got hosed hard, or you got misled. No way in hell I would do that job for 2 hours labor. Book time is 5.5 hours for the timing chain, which would include R&R of the balancer. Either these guys were high on crack and gave away the bank, or maybe they only did the balancer, which is 1.2hrs +.4 add with A/C, and charged you a little extra for check out. That's my guess.
I work in the auto repair industry and have for nearly 40 years now. I proudly consider myself one of the top techs. Not because I know it all, no one knows it all. But because I take the time and make the effort to be one of the top techs.
If you bring your car to me, it will be diagnosed accurately and repaired absolutely correctly, using correct methods and quality parts, and you will pay me for it. Options are, take it to the cheaper option down the street and have fun with that, or learn to do it yourself.
If you do perform your own repairs just please don't be a hack. Take the time and effort, and buy the tools, to do it right. That way, if one day you do bring your car to me or someone like me, we don't end up spending alot of time and your money fixing things your broke. I spend enough time fixing things ruined by the cheaper option down the street.
I work in the auto repair industry and have for nearly 40 years now. I proudly consider myself one of the top techs. Not because I know it all, no one knows it all. But because I take the time and make the effort to be one of the top techs.
If you bring your car to me, it will be diagnosed accurately and repaired absolutely correctly, using correct methods and quality parts, and you will pay me for it. Options are, take it to the cheaper option down the street and have fun with that, or learn to do it yourself.
If you do perform your own repairs just please don't be a hack. Take the time and effort, and buy the tools, to do it right. That way, if one day you do bring your car to me or someone like me, we don't end up spending alot of time and your money fixing things your broke. I spend enough time fixing things ruined by the cheaper option down the street.
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Re: 305 tpi bad harmonic balancer
BTW, The tech that did that repair job got hosed hard, or you got misled. No way in hell I would do that job for 2 hours labor. Book time is 5.5 hours for the timing chain, which would include R&R of the balancer. Either these guys were high on crack and gave away the bank, or maybe they only did the balancer, which is 1.2hrs +.4 add with A/C, and charged you a little extra for check out. That's my guess.
I work in the auto repair industry and have for nearly 40 years now. I proudly consider myself one of the top techs. Not because I know it all, no one knows it all. But because I take the time and make the effort to be one of the top techs.
If you bring your car to me, it will be diagnosed accurately and repaired absolutely correctly, using correct methods and quality parts, and you will pay me for it. Options are, take it to the cheaper option down the street and have fun with that, or learn to do it yourself.
If you do perform your own repairs just please don't be a hack. Take the time and effort, and buy the tools, to do it right. That way, if one day you do bring your car to me or someone like me, we don't end up spending alot of time and your money fixing things your broke. I spend enough time fixing things ruined by the cheaper option down the street.
I work in the auto repair industry and have for nearly 40 years now. I proudly consider myself one of the top techs. Not because I know it all, no one knows it all. But because I take the time and make the effort to be one of the top techs.
If you bring your car to me, it will be diagnosed accurately and repaired absolutely correctly, using correct methods and quality parts, and you will pay me for it. Options are, take it to the cheaper option down the street and have fun with that, or learn to do it yourself.
If you do perform your own repairs just please don't be a hack. Take the time and effort, and buy the tools, to do it right. That way, if one day you do bring your car to me or someone like me, we don't end up spending alot of time and your money fixing things your broke. I spend enough time fixing things ruined by the cheaper option down the street.
#24
Re: 305 tpi bad harmonic balancer
Yeah, I was thinking 2 hours was damn fast. I don't have any book, but I know what it entails. Dropping the pan alone is a PITA on these cars. And it has to be done to get the timing cover off and replaced with no chance of leaks.
#25
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Re: 305 tpi bad harmonic balancer
Yeah. Buddy deals are nice. You owe him big time. The pan needs to come off to properly install the timing cover. I've seen timing covers that were taken out without dropping the pan and then modified to reinstall, again without dropping the pan. This means trimming the wings off at each side. It's these wings that secure the end seal in place. Some guys swear that they do this all the time and never have an issue. It makes me a little nervous. The ones I've gotten in that we're done this way always look hacked up. They leave with new timing covers. I've seen aftermarket timing covers with the wings already trimmed but I won't use them. I've had the lip seal between the cover and pan push out, even when everything seemed to fit well. That's why I don't mess with anything but the right way. It's even more of an issue with the one piece pan gaskets on the 87+ motors.
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Re: 305 tpi bad harmonic balancer
Ain't that the truth. I just went through dropping the oil pan on mine. I wish it would have only taken 2 hours. lol.
#27
Re: 305 tpi bad harmonic balancer
I've seen nipping off the corners of the timing cover inside lip done before. Not my cup of tea. I'd rather go through the extra work and do it right.
#28
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Re: 305 tpi bad harmonic balancer
JOE.........YUP
The shortcut way its done in MOST shops so they don't have to drop the pan
is to "trim the horns" on the timing chain cover on a SBC motor..................
Thats why I like a Pontiac motor!
The shortcut way its done in MOST shops so they don't have to drop the pan
is to "trim the horns" on the timing chain cover on a SBC motor..................
Thats why I like a Pontiac motor!
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Re: 305 tpi bad harmonic balancer
I need a cherry picker to replace my motor mounts....talked with a 'mechanic' who told me, yeah no need for the hoist, just raise the engine with a floor jack under the harmonic balancer
When I said no way in hell am I doing that, his second suggestion was taking the floor jack, block of wood, and lifting under the oil pan
I have not spoken with him since.
#30
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Re: 305 tpi bad harmonic balancer
The engine crane makes it hard to access the motor mounts because the hoist legs extend under the car. Bad enough getting to the nuts inside the front crossmember with the lower control arms installed. If you have use of a rack, you can use a safety support stick, one of the narrow screw type, to raise one side at a time by the motor mount brackets, the accessory brackets, or any other solid part of the engine accessible with the stick`s pad, which is real compact. Of course pay close attention not to bend or otherwise damage anything. I have seen several engines raised or supported for various reasons by the balancer. I hate to see it too but sometimes it makes sense. As long as your not bouncing the engine around, it's not as bad as sounds. I've never seen a bent crank from it. Seen a few from people leaving the breaker bar and socket on the balancer bolt when they start the motor. Oops!
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Re: 305 tpi bad harmonic balancer
Besides the fact, that if you do end up damaging the internals in some way, you're back at square one, and absolutely *have* to buy a hoist in order to pull the engine now!
Leave the flip-flops to beaches and politicians, buddy!
#32
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Re: 305 tpi bad harmonic balancer
phantom whatever, If you're not going to ask valid questions or provide some kind of useful information, find another forum upon which to spew your negative crap. Also, don't quote me if you don't know what you're talking about. I started wrenching in earnest in 1974, and have worked as a professional auto technician since 1976. I've repaired thousands of vehicles, more than I could ever count or even try to remember. I've overhauled or done major repairs on hundreds of engines of all makes and sizes and have built more high performance Small Block Chevy V8s that you'll probably ever see in your lifetime. I do top quality work because I won't accept any less of myself.
If supporting the engine by the balancer magically causes your engine to fail, you had bigger problems. If you ever saw slow frame video of a crankshaft in an engine running at speed, especially in a high horsepower engine, well let's just say you'd understand why they make the best crankshafts out of chrome moly. You'd also understand that the crankshaft in operation is anything but straight with constantly changing twisting forces placed on it. The weight of the engine on one end of it, isn't likely to hurt it any. I already said I don't like the idea of supporting the motor by the balancer. However, as I said before, I've also seen it done many times on all makes of engines and have never seen it cause any damage, at all, period. I've also seen plenty of bent up TPI runners by people trying to lift the engine with a crane without pulling the intake. You will find that raising the motor, especially TPI, sufficiently to replace motor mounts, with a crane, is not as easy as it sounds.
The best method that I have found, for doing motor mounts on these and many other GM rear wheel drive vehicles using a crane, is to lift one side of the motor at a time. You will want to disconnect the exhaust at the manifolds first and keep a close watch on hoses and wiring so not to over-stretch anything. You need to disconnect both motor mounts first by removing the through bolts. As you set the motor back in place on the new mounts, you will need to help the mount brackets back onto the mounts. They have alignment notches that need to sit in place correctly before the through bolt will go back in. You can help them along by moving the crane back and forth from one side of the motor to the other and gently raising til the mounts drop into place. It helps some to leave the mount bolts to the frame loose until the through bolts are in. The stick method I mentioned before works just as well, but you have to have a the car on a lift. BTW, don't forget to pull the dist cap and the dress cover at the rear of the plenum to avoid breaking either one.
If you use polyurethane mounts, which are a good idea if you plan on making any power, be aware that on some brands, the alignment tabs are a little shorter than on the OE mounts and the bracket may try to slip past them and make installing the through bolt harder than usual.
The hardest part of the job is accessing the nuts of the mount to frame bolts. They are inside the crossmember and the control arms do a good job of blocking access. I have had some success using a wobbly socket to hold the nut and breaking the bolt loose by the bolt head. I also have had success on some using an end wrench, but either way it sucks. If you do use a wrench, be sure to have a magnetic retrieval tool handy to retrieve the wrench when you drop it inside the crossmember.
If you are thinking of rebuilding the front suspension with new A-arm bushings and ball joints, while you have the A-arms out would be a great time to do the motor mounts.
If supporting the engine by the balancer magically causes your engine to fail, you had bigger problems. If you ever saw slow frame video of a crankshaft in an engine running at speed, especially in a high horsepower engine, well let's just say you'd understand why they make the best crankshafts out of chrome moly. You'd also understand that the crankshaft in operation is anything but straight with constantly changing twisting forces placed on it. The weight of the engine on one end of it, isn't likely to hurt it any. I already said I don't like the idea of supporting the motor by the balancer. However, as I said before, I've also seen it done many times on all makes of engines and have never seen it cause any damage, at all, period. I've also seen plenty of bent up TPI runners by people trying to lift the engine with a crane without pulling the intake. You will find that raising the motor, especially TPI, sufficiently to replace motor mounts, with a crane, is not as easy as it sounds.
The best method that I have found, for doing motor mounts on these and many other GM rear wheel drive vehicles using a crane, is to lift one side of the motor at a time. You will want to disconnect the exhaust at the manifolds first and keep a close watch on hoses and wiring so not to over-stretch anything. You need to disconnect both motor mounts first by removing the through bolts. As you set the motor back in place on the new mounts, you will need to help the mount brackets back onto the mounts. They have alignment notches that need to sit in place correctly before the through bolt will go back in. You can help them along by moving the crane back and forth from one side of the motor to the other and gently raising til the mounts drop into place. It helps some to leave the mount bolts to the frame loose until the through bolts are in. The stick method I mentioned before works just as well, but you have to have a the car on a lift. BTW, don't forget to pull the dist cap and the dress cover at the rear of the plenum to avoid breaking either one.
If you use polyurethane mounts, which are a good idea if you plan on making any power, be aware that on some brands, the alignment tabs are a little shorter than on the OE mounts and the bracket may try to slip past them and make installing the through bolt harder than usual.
The hardest part of the job is accessing the nuts of the mount to frame bolts. They are inside the crossmember and the control arms do a good job of blocking access. I have had some success using a wobbly socket to hold the nut and breaking the bolt loose by the bolt head. I also have had success on some using an end wrench, but either way it sucks. If you do use a wrench, be sure to have a magnetic retrieval tool handy to retrieve the wrench when you drop it inside the crossmember.
If you are thinking of rebuilding the front suspension with new A-arm bushings and ball joints, while you have the A-arms out would be a great time to do the motor mounts.
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