Harmonic Balancer Confusion

I am going to piggy-back off of this thread. My problem area revolves around the harmonic balancer and crank pulley. I took my 1966 coupe out recently on the highway and noticed some strange vibrations so I decided to head home. While on the way back the crank pulley came off. It went flying under the car and gave me quite a scare for a few secs. I brought the car to stop very quickly on the side of the road and had a tow truck take us home. The coupe sits in the garage now. The crank pulley bolts are simply sheered off the balancer and all the belts are hanging down now. I believe I need a new harmonic balance and new crank pulley. I have looked on Summitt and some mustang sites for what I need. The car has a 289 w/ a T-5 trans and Edelbrock aluminum heads, high rise aluminum intake, holley 650 carb, Edelbrock high flow water pump, and Edelbrock cam which the specs I do not know of since the car was built before I purchased the car. It appears the harmonic balance is the stock one or something very similar. I will post pictures of it as soon as I can.

Could I use a new stock type replacement (since they are less expensive) or do I need something better and more advanced? How do I get the balancer off, does it make a difference if the crank pulley already broke off? I am going to attempt to repair this myself w/ my father's assistence but neither of us have done this before. I need to do this on a very very tight budget. Any help if greatly appreciated.

you can use a stock replacement balancer as long as you use one that has the right balance factor. if your engine is a 28oz balance engine, then use the early balancer. also make sure you use the right bolt pattern balancer. up to 69 the small block ford used a 3 bolt pulley, and after that they used a four bolt pulley.

as for removing your old balancer, you will need a balancer puller. you will also need to remove the pulley bolts, what is left of them, probably by drilling them out and using an easy out. dont drill them too large as you lose the threads needed to bolt the balancer puller to. there is also a large bolt that goes into the crankshaft that needs to be removed as well.

one bit of advice, as long as you have the balancer off, replace the front cover seal to avoid leaks in the future, unless it is fairly new.

rbohm said:

you can use a stock replacement balancer as long as you use one that has the right balance factor. if your engine is a 28oz balance engine, then use the early balancer. also make sure you use the right bolt pattern balancer. up to 69 the small block ford used a 3 bolt pulley, and after that they used a four bolt pulley.

as for removing your old balancer, you will need a balancer puller. you will also need to remove the pulley bolts, what is left of them, probably by drilling them out and using an easy out. dont drill them too large as you lose the threads needed to bolt the balancer puller to. there is also a large bolt that goes into the crankshaft that needs to be removed as well.

one bit of advice, as long as you have the balancer off, replace the front cover seal to avoid leaks in the future, unless it is fairly new.

Click to expand...

I believe I need the 28oz / 3 bolt. That is what it appears to be when I match it up to parts listed on auto supply websites.

Do I really need to remove the pulley bolts? There does not appear to be any place these go into expect the balancer and that is only attached w/ the large main bolt. If I took that off the whole thing should come off, correct?

Do you mean the timing cover gasket, similar to these?
AutoZone.com | Vehicle Selection | Year

Which one do I go with?
W/o sleeve "N" seal Water pump to plate gasket not included.
or
W/sleeve "N" seal Water pump to plate gasket not included.

When I went to my local Autozone the tech stated I needed the W/ sleeve "N" seal

creedog said:

Do I really need to remove the pulley bolts? There does not appear to be any place these go into expect the balancer and that is only attached w/ the large main bolt. If I took that off the whole thing should come off, correct?l

Click to expand...

you do need to remove the pulley bolts, or what is left of them. otherwise you have no place to bolt the balancer puller to. remember that the balancer is a press fit, and the large bolt in the crank is there to prevent the balancer from coming off if that fit should be a bit loose.

Do you mean the timing cover gasket, similar to these?
AutoZone.com | Vehicle Selection | Year

Which one do I go with?
W/o sleeve "N" seal Water pump to plate gasket not included.
or
W/sleeve "N" seal Water pump to plate gasket not included.

When I went to my local Autozone the tech stated I needed the W/ sleeve "N" seal

Click to expand...

all you need is the seal that ride on the balancer snout as i recall. i dont think you need to pull the timing cover to replace the seal.

rbohm said:

you do need to remove the pulley bolts, or what is left of them. otherwise you have no place to bolt the balancer puller to. remember that the balancer is a press fit, and the large bolt in the crank is there to prevent the balancer from coming off if that fit should be a bit loose.



all you need is the seal that ride on the balancer snout as i recall. i dont think you need to pull the timing cover to replace the seal.

Click to expand...

Ok, My confusion then. I thought since I was going to replace the entire harmonic balancer that I would not need to mess w/ the broken pulley bolts. The seal you are referring to might be called the harmonic balancer sleeve?

AutoZone.com | Vehicle Selection | Year

Thanks for all the help...

This may seem to be a simple but silly question, but which crank pulley do I need? 2 or 3 groove crank pulley? Remember it broke off while I was driving home on the highway so it is a lost cause as far as I am concern. Per this link it states... "It attaches to the harmonic balancer and drives the altenator, water pump & power steering belts." But I do not have power steering on the coupe. I believe this is the correct one because my car is a '66 w/ a 289. I am going to get their non-hi-po harmonic balancer for 65/68 w/ 260/289 and this looks exactly like the stock one on the car.

http://www.mustangsunlimited.com/itemdy00.asp?T1=56312B+01

If you don't have PS or AC you need only one groove, not two. Check the diameter of the pulley vs. the water pump pulley, I have seen them very close even when stock, and some replacement types interfere (overlap) which won't work.

Sorry I forgot to mention I do have the original A/C on the car. So the 2 groove then?

creedog said:

Sorry I forgot to mention I do have the original A/C on the car. So the 2 groove then?

Click to expand...

Absolutely not! With AC you must have the third groove, the second one simply does nothing if you don't have PS. This one is chrome, but of course they also come in black:

Update - a purchased a used 3 groove crank pulley in very good condition and just received the new harmonic balancer (non HiPo version) for my '66 289ci. I also purchased three bolts to install the crank pulley to the balancer. If someone can please let me know if I have the correct ones. I got 3/8 course thread, 3/4" and 1" length (3 of each - not sure what length I need) hex nuts with tightening washers (for the pulley). These are the brass covered version but are grade 8 strength bolts as marked at the local Ace Hardware store.