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Changing harmonic balancer 3.8

what is the easiest way to loosen the bolt holding the harmonic balancer (damper pulley) to the crankshaft on a 3.8L 88 olds?

I’m assuming you’re asking because you don’t have a strong impact wrench or a specialty tool to hold the crank from turning.

One technique is to remove the starter and place a prybar or stub of wood up against the torque converter ring gear, and wedge it in place so the engine won’t turn. The rest should be simple with a decent 1/2" breaker bar and socket on the crankshaft bolt.

Use use 3 jaw puller to remove balancer. Do u need special tool to install balancer? Or just tap it on with hammer/wood block?

Impact wrench I have may work, I was thinking of setting a breaker bar on it with a pipe then hit the starter. thing is i am not sure which way the motor turns. I could disable the fuel pump so it doe snot start.

On my Corolla there is a set of two holes on the side of the pulley. With the right tool, you can insert the pins on the tool into those holes, then wedge the other end against something, to hold the pulley still while you socket the center bolt loose. I made this tool with a piece of plywood and a couple of wood screws appropriately spaced for the pins, and it worked. But later I noticed I could have purchased one from Harbor Freight. I can’t see it there now, maybe they no longer stock it, but it sort of looks likes this, only the handle is longer.

Anyway, if you don’t have an impact wrench, look for some holes on the pulley provided conveniently by GM. You might be able to parlay those into the desired result.

One add’l caution: You’ll likely have to use a puller to remove it, after the bolt is loosened. Loosen the bolt, but leave the bolt in part way so the puller has something to pull against, and to avoid damaging the threads. But be very careful, as it is easy to pull to much and damage the balancer. You just want to get it unstuck, then you can remove the bolt and pull it off by hand.

I see remove techniques but no install comments

I have a business near me where I am in good terms with. I borrowed a 3/4 drive impact which took the bolt right off. Mine would not. The balancer I replaced was shot but the one i purchased was made in China, I was under the auspices that it was a Dorman. Does anyone know if Dorman is Chinese?

Dorman is not Chinese, it is a US company, the headquarters are in PA, listed on the NASDAQ as DORM. They sourced the part in China.

I have bought several Dorman parts over the years

Most of them did their job correctly, but they were ALL made in China

George, another tool that can be used on the Toyota engine. parts list 1 ea 1x4 about 15" long, 2 ea 8x1.25x40mm class 12.2 bolts (or 4 class 8.8).

This might work on any engine.

It is a done deal, as i said i used the 3/4 inch impact wrench from a local business which took it right off. Couple things for future knowledge, no holes you can lock the harmonic balancer. The only holes are the ones for balancing. There is also no way to put a 3 claw pulley puller on it due to the inner structure or frame rails. I was able to get two claws in just enough at a slight angle to pull off the pulley. It was slow but worked. this pulley says made in China, I was somewhat dismayed!
thanks for all the imput.

Thanks for the follow-up @grego2 … sounds like for this one you have to have an impact wrench to remove the crank bolt. The pin tool won’t work.

@keith … yeah, I made one like that for the Corolla, only out of plywood. And not so professional looking. I’m pretty sure I saw one that looked like yours (with a long handle, only made of metal, and the pin placement was adjustable) in a Harbor Freight catalog a few years ago, but I don’t see a reference to it now. I don’t see how that spinning tool would help. Or how it works.

Even with a shop full of tools and equipment I have often used a breaker bar propped on a block of wood and bumping the starter to loosen harmonic balancer bolts. It can be dangerous if not thought out and done carefully. Jamming a piece of carpet between the wrench and subframe works well. Holding the wrench, or even standing in striking distance would be a mistake. It’s a shade tree method that I learned long ago that has saved me time and trouble over the years.

That’s a clever idea @RodKnox ! Provided the crank shaft turns the right direction w/respect to the threads. Sort of a built-in impact wrench. Also, I can see how, if not done safely, it could go bad! I’m envisioning wrenches and breaker bars flying everywhere … … lol …

If I remember right, when my timing chain went on my Buick 3800, I had a heck of a time holding the engine to loosen the nut. Didn’t have any problem with the nut but just trying to keep the balancer from turning. Tried a variety of methods and think I finally just blocked the crankshaft since the pan had to come off anyway.

Speaking of cranking motor and using breaker. Friend got serp belt misaligned and cranked motor and balancer tugged on belt which was skewed on tensioner and yanked tensioner hard enough to snap tensioner bolt off. Bolt was now in really bad spot to remove via ez e out.