What is the best replacement harmonic balancer for a stock 86 L98 with aluminum heads? How difficult is a new balancer to install? Are there any shortcuts or installation tips?

 

The best replacement for a stock part would have to be another stock part. If you dont have a either a high rpm custom engine or an exotically balanced engine there is no gain to be had buying anything aftermarket. As far as the removal and reinstallation it isnt a difficult task. You will need to go to a parts house and ask for a harmonic balancer removal tool. Then get either a FSM or a chiltons/haynes manual. This is job takes about 3 hours tops. I had one shell out on my 85 and the outer weight moved aft until it cut into the timing chain cover. Good luck.

 

And stay with the stock size. I believe it is 6 3/4" A larger one will hit the crossmember.

 

On my former 86,I bought a new GM one.

I already had a steering wheel/balancer puller and just removed the hard power steering lines on the rack to gain a little more clearance to get the balancer off.It came off easy.

I DID,however,buy the moroso balancer install tool from summit racing for about 40 bucks.Not one shop had a loaner tool,not even autobones.
Now I have the tool if I ever need it.Made install a breeze.My neighbor that fixes engines has borrowed it many times.

The tool makes it easy to press the new balacer back on with ease.Use some anti seize on the crank to help balancer slide on,and be sure the keyway is in good shape.

 

I replaced my late 86' (aluminum head) with a "Doorman" unit I believe. I got it from AutoZone (Part# 155385, or 594-012 they are both listed on the reciept). It was $52 (one year ago). The puller I bought from Autozone worked great, but the installer did not. I had to go to Advance to get a proper installer kit (loan a tool program).

As mentioned, it takes about 3 hours. A little less if your car is a manual. My car was an auto, so I had to lift the front end and remove the flywheel cover so I could use a box end wrench on the flywheel bolts to hold the engine still while I removed the balancer.

You do NOT have to loosen the steering rack, just the one fluid line in front of the balancer.

I took a few pics of the process (including the WRONG install kit). You can see them here

http://members.***.net/effergyvette/..._balancer.html

Hope that helps!

 

Thanks guys. I appreciate the good advice.

 

Pretty graphic pics of the failed damper...

 

Replaced mine with stock. Would have preferred a solid damper. There is a rubber ring on this thing that will come loose after a while. I found this out after trying to set timing. My mark had dissapeared.

 

That is NOT the wrong install kit. That is the CORRECT kit. Just because none of the threaded tips worked in your car's crank snout does not mean it won't fit his. I used that exact same kit with success. The kit you got probably had a duplicate size adapter tip mixed in there from another kit. That or your crank had different size threads for whatever reason.

Don't bother paying a premium for a GM damper at the dealer. It's foreign made anyway just like most of their parts like AC Delco now are.

The only damper you need is about at $60 at Autozone. If the stock one lasted you this long, that's a pretty good indication of how long a new quality stock style one ought to last.

Dorman brand balancer part# 594-012
I bought it from Autozone, pictured below. You'll need to fill the timing mark with something white so you can see it when timing the car. You can smear toothpaste into the crack, or white pipe sealant compound and wipe the excess off. Leaving only the timing mark filled.




On a stock motor, buying an expensive aftermaket damper is a waste of money IMO. The stock damper is all you need.

For this job, you need two special tools. Rent them from Autozone. Leave a deposit, get your money back upon returning them. Basically free.

Balancer Removal tool# 27144



Works the same as a steering wheel puller. The shinny cone tip goes on the end of the main shaft, and into the crank thread hole. The cone acts as the pivot point as you turn the tool. Use a deep socket to turn it. A deep socket acts as a cup and shields the puller's shaft threads from rubbing on the steering rack as you turn. But first you must hold the engine stationary while you remove crank bolt, or the whole engine just spins on you. I wedged my flywheel with a wrench while I broke the crank bolt loose with breaker bar like this. Upon reinstalling crank bolt, I put the wrench on the other side of exhaust pipe to hold engine the other way:


That was before I had a chain wrench.

So you can also use a chain wrench around the old balancer or crank pulley to hold it statonary while you break the crank bolt loose. Put a folded shop rag under the wrench teeth if using it on the crank pulley. Let the handle wedge itself against the frame, and the engine won't even budge. The crank bolt is real tight and probably has thread lock on it from the factory. You need a breaker bar for that bastard.



Most chain wrenches only have enough chain for about a 5 inch pulley. I bought two from sears, and took the chain from one, and doubled the length on the other. Could not find just the chain for sale. Now I can use it on just about anything.



Kit comes with different sized thread adapters (A). Find the one that will thread into your crank snout. I forgot what size I used, but it was in the kit for sure. If none fit, make sure you don't have two of the same size in the kit. Or use your crank bolt to match up the threads.

How to use:
Orientate the tool as follows.

Arrow toward engine.
A threads into crank bolt hole. Back female end of A threads into front of bolt D (threads hidden in pic).
Hold shaft C stationary with small crescent wrench by the notched end of it (let this small wrench wedge itself against the frame, instead of trying to hold it with your other hand), while you turn nut B with large cresent wrench. Nut B presses roller washer against balancer while the head and threads of bolt D stops rearward movement, forcing balancer forward onto crank snout. Roller side of washer goes against the balancer. Lube tool threads.

Stop when you feel the balancer bottom out. Remove tool and mount crank pulley with bolts only hand tight. Check for proper pulley aligment relative to the other engine pullies. If it's good, the balancer is seated all the way.



To use these tools, you need to pull the radiator fan, MAF, and accordion air duct to create working room.

You also need to undo the top steering rack line and move it to the side because it sits right in the way of the tool. Use a crowfoot socket with a few long extensions for ease of removal of upper rack line.

 

I've never changed out the balancer on C4, but on another vehicle (6.2 diesel), I used an impact gun to remove the balancer bolt This is significant because if you use the imapct gun, you won't need to remove the inspection cover on the bellhousing. The motor won't turn because the impact gun uses percussion rather than torque to loosen the bolt. I was able to grab the balancer with my hand and prevent it from spining long enough to back the bolt out. I was also able to put it all back together without blocking the flywheel. I did not use the impact gun for setting the final torque. I used a cordless impact gun. The puller/installer info here is spot on. I bought both pieces from NAPA for not much money.

 

Yes, if you have an impact gun, I'd first try to wiggle that into position to break the crank bolt loose. It might fit. Since I did not have one at the time, I can't say for sure that it will or won't.

 

Note: Every Corvette owner should own CORDLESS impact gun. Also an impact swivel and an extension would overcome some of your clearance issues.

 

This?

 

Yes, something just like that. There's also plug in models, but you can't take them with you on roadtrips for changing flats by the side of the road.

I personally own this one:
http://buy1.snapon.com/catalog/item....re&dir=catalog

Mine is an 18v and it's plenty powerful. That 24v one ought to twist some wrists. I believe the one pictured there is from Harbor Freight or Northern. If you get it from them, get the warranty. Seems like everything I get from them either requires re-work or is only good for 1.5 uses. I might look at Sears, they're probably running some black Friday sales. This is a tool you're going to be using more than you'll think.

 

I know this is a zombie thread but I read it before my current HB replacement.

You have the right puller and and installer? Remove the MAF and plenum, take off that power steering tube. That's it. The engine doesn't turn when you loosen the bolts (at least mine didn't), although the puller will turn the engine. See that solid metal below the front of the crank? Put a block of wood at 3 o'clock under the puller and it will hold it in place while you pop the HB off. No worries. Use deep sockets.

The biggest problem was changing the seal. I'm still working on that this Saturday afternoon It doesn't want to come out.

 

Correction: you don't take OFF the power steering tube, just remove the flare nut and bend the tube up a little so it's out of the way. Be sure to put a pan underneath 'cause you're gonna drip PS fluid.

 

Seal came out by putting a sharp long screwdriver on the top and whacking it with a hammer a few times. I sharpened it on my slow speed grinder first... Tapped in the new one with very small hammer taps, trying different hammers till it seated.

Remember to put the pulley on before you put the HB bolt in (don't ask me how I know). Added a little blue lock tite.

 

FWIW - replaced mine with a new GM OE replacement from my local dealer, and I have an old, made in the USA puller, so a fairly easy job - overall a little work, but not hard work. it all just boils down to nuts and bolts anyway -

 

It is worth something for sure, made in USA is one reason I own an older American car. Still more or less made in the USA. However, I confess I bought the HB from NAPA and it said right on it, made in China. *gag*

 

If you want the best then I suggest FluidDampner as they never wear out. For street use #670100 or for SFI racing approved the #620103. Not cheap but the best should outlive your car/motor.