F Body VS B Body LT1 balancer and bracket alignment problems

[gvincent]

I should of posted this thread first.

I was swapping all my accessories and brackets over from the F body LT1 to the B body LT1 and now the B Body harmonic balancer pulley is at least a 1/2" further out from the block??? all my F body pulleys with the F body bracket do not line up!

The F body and the B body Balancer do look the same but the Hubs are not. It seems the B body hub sticks the balancer out further by about a half an inch, The pulleys for the F body are a 1/2 inch further back, I measured the balancer from the block and came up with a about 4-1/2" on the F body motor and 5" on the B body motor.

I attached some pictures

What's Up?? I thought they would of been the same.

Have others encountered this?

Should I shim out the F body accessory bracket, cut and extend the rear alternator support rods or change/swap over the Hub?

I think I would rather shim out the bracket it seems others have run into problems removing the hub, destroying the threads in the crank or other nasty stories and messing with the orientation due to the crank/hub being keyless.

Another pause in the road..... Damm!!!

[dts300z]

I have a spare 95 lt1 F-body hub. I noticed the difference when I was mocking up some parts on my spare caprice lt1.

 

As for swapping out the hub if you have the right puller you won't run into problems here. Note that it will also require an installer as well. They are not that difficult I have done several. Just be sure you index the crank correctly. You will notice on the hub/balancer that there is a casted in triangle between two of the ears, this little triangle should be pointing to the keyway in the crankshaft. Pretty simple really.

[gvincent]

dts300z,

Thanks for the response.

Do you know what puller and installer is needed? Is this something you can rent from AutoZone? What do they look like?

I looked inside my hub and it is a little rusty. I should probably start spraying Liquid Wrench in there nightly.

I thought there was no keyway on the LT1 cranks?

I know about making a mark to line up the triangle again like I did when I removed the balancer to put in the new OPTI-Spark.

How much do you want for the F-body hub?

Funny you have a spare Caprice LT1 and I have a Spare Caddy LT1 which I am now having to swap in because the 80K F-Body decided to develop a rod knock while still on Jack stands!

 

Thanks,

Greg

 

I have a spare 95 lt1 F-body hub. I noticed the difference when I was mocking up some parts on my spare caprice lt1.

 

As for swapping out the hub if you have the right puller you won't run into problems here. Note that it will also require an installer as well. They are not that difficult I have done several. Just be sure you index the crank correctly. You will notice on the hub/balancer that there is a casted in triangle between two of the ears, this little triangle should be pointing to the keyway in the crankshaft. Pretty simple really.

[dts300z]

dts300z,

Thanks for the response.

Do you know what puller and installer is needed? Is this something you can rent from AutoZone? What do they look like?

I looked inside my hub and it is a little rusty. I should probably start spraying Liquid Wrench in there nightly.

I thought there was no keyway on the LT1 cranks?

I know about making a mark to line up the triangle again like I did when I removed the balancer to put in the new OPTI-Spark.

How much do you want for the F-body hub?

Funny you have a spare Caprice LT1 and I have a Spare Caddy LT1 which I am now having to swap in because the 80K F-Body decided to develop a rod knock while still on Jack stands!

 

Thanks,

Greg

 

You can use this puller http://shop.advanceautoparts.com/productdetail.aspx?MfrCode=PBI&MfrPartNumber=648436&CategoryCode=3497

 

You can look around for a specific puller for the LT1 but I use the one above and I insert a long 1/4" extension into the bolt hole for the puller to push against.

 

I don't advertise my installer as it is not a good practice... lol.

 

There is a keyway on the crank just not one in the hub.

 

I could sell you my extra one but you might look at the JEGS hub as it is keyed and a very nice piece for a decent deal. I picked one up. http://www.jegs.com/webapp/wcs/stores/servlet/KeywordSearchCmd?storeId=10001&catalogId=10002&langId=-1&N=0&Ntt=lt1+hub&Ntk=all&Nty=1&D=lt1+hub&Ntx=mode%2Bmatchpartial&Dx=mode%2Bmatchpartial&searchTerm=lt1+hub

[gvincent]

Thanks again,

 

I will probably give the hub swap a try. Any special tools required for installing the hub back on? I read somewhere not to hammer it on as this could cause damage to the internal bearings and that is all I need is to have 2 LT1's with bearing problems and still have not driven 1 mile yet.

If I don't get the Jegs hub how much do you want for your spare?

 

I didn't want to spend anymore money on the Caddy motor. As it is I just bought that motor so I can at least finally get some drive time this summer after almost 3 years of working on this swap. Then next fall I will decide to either re-build the f-body LT1 or go old school with a 400SBC and get rid of both LT1's

Thanks,

Greg

You can use this puller http://shop.advanceautoparts.com/productdetail.aspx?MfrCode=PBI&MfrPartNumber=648436&CategoryCode=3497

 

You can look around for a specific puller for the LT1 but I use the one above and I insert a long 1/4" extension into the bolt hole for the puller to push against.

 

I don't advertise my installer as it is not a good practice... lol.

 

There is a keyway on the crank just not one in the hub.

 

I could sell you my extra one but you might look at the JEGS hub as it is keyed and a very nice piece for a decent deal. I picked one up. http://www.jegs.com/webapp/wcs/stores/servlet/KeywordSearchCmd?storeId=10001&catalogId=10002&langId=-1&N=0&Ntt=lt1+hub&Ntk=all&Nty=1&D=lt1+hub&Ntx=mode%2Bmatchpartial&Dx=mode%2Bmatchpartial&searchTerm=lt1+hub

[dts300z]

pm sent.

[piston]

i experienced with both motors b and f and the balancer dont line up like how you mentioned. when you use the tool to pull the balancer, make sure it pulls evenly. your probably going to want to mark your balancer and crank as it has no keyway for some stupid GM reason. soak it good with pentrating oil and make sure you use a good quality tool. i got a rental one from autozone and it works ok but returned it with a damaged head. lol. when you put it back on, line it up with the markings you made as it is pressed on or goes on by tightening the crank bolt. again with no keyway, it just goes back on however or with the marks you made to be most accurate.

 

i broke my balancer bolt into my crank and drilled for 7 hours and had to replace my block. i was pissed but it was a learning experience. that gave me an excuse to go with the real lt1 with alluminum heads as rebuilding the old block would cost more than buying another used block.

[wheelman]

I also busted the balancer bolt in the nose of my crank the first time I reinstalled the balancer. Fortunately for me the bolt busted right where it enters the crank so I was able to use a screw driver and a pair of pliers to work it back out. Then I later stripped the threads in the crank and had to use inserts. The bottom line is use a torque wrench when you are tightening that bolt and DO NOT EXCEED 70 FT/LBS. The hub will look like it's not fully seated when in fact it is, if you keep torqueing the bolt to seat it more you'll either bust the bolt or strip the threads.

 

Needless to say I do not look forward removing the balancer.

 

BTW: It doesn't matter if you put the balancer back on in the same orientation as it came off, that's why it's not keyed. There are no timing marks on it and you can't time the engine by adjusting the opti anyway. It's nice to have the triangle indicate TDC but it won't affect the balance of the engine if it doesn't.

[piston]

hahaha, i was dumb then. i thought the little 3 marks around the balancer ring was for that. i worked so fast i never got to the timing deal. but the car ran great so i left it and went no further.

 

i think i cross threaded my bolt, thats why it was kinda tough going in but it seemed pretty straight. the worst thing was when i broke my bolt in there, i used a cheapy easy out and that f**ker broke in there too and will not drill for shiet. lol. that was so long ago and i think i remeber posting something about this.

[gvincent]

Well we have success, I was able to remove my balancer and hub from the F-body motor and remove the hub and balancer from the B-body motor.

I marked them before they were completely off and then noticed a mark left on the inside of the hub left by the keyway, It wasn't an engraved mark just that the inside of the hub had a stripe of slightly darker metal or an oil mark I noticed on both hubs before I wiped them clean. I am sure if I had twisted or turned the hub while removing it the mark would not be there. I just made sure that the mark left by the keyway slot lined up with the keyway.

I Torked it to the 70Lbs and it looks good to go.

I didn't put the B-body hub onto the broken F-body motor as I will never use it, so If anybody needs a B-Body hub I have one.

Putting the hub back on I had to go out and get a longer bolt to get it started and then swapped the bolt out once it was on far enough to use the original bolt and spacer/washer. I didn't want to hammer anything!

Thanks all

Greg