1990 mercruiser 3.0 harmonic balancer coming off

[Chasefamily]

I have a 1990 mercruiser 3.0. Was out on the water and weird flapping noise coming from front of motor. Figured out it was from the belt area. Went home and checked closer and noticed that the harmonic balancer isn't lined up with the idler pulley of the alternator. It looks like it has worked itself out about a 1/4 inch. What holds this balancer in?

 

[Bondo]

Ayuh,.... Welcome Aboard,..... It's a press-fit on the crankshaft,....

 

[Alumarine]

Are you sure it's coming off the snout or is it the outer part of the balancer that is separating from the rubber part?

As Bondo said it's pressed on and you will need a harmonic balancer puller to remove it.

 

[Chasefamily]

I'm honestly not sure, looking at it you can see that it's not lined up. I used a block and hammer to push it back in, so now everything is lined up. I'm guessing it will just work it's way out again?

 

[Alumarine]

I'm honestly not sure, looking at it you can see that it's not lined up. I used a block and hammer to push it back in, so now everything is lined up. I'm guessing it will just work it's way out again?

Was it the outer part that was out of alignment or the part on the crankshaft?
In either case they don't tend to cause trouble when they're ok.

 

[Scott Danforth]

Replace it

 

[76SeaRay]

I don't know about a 3.0L but V8's typically have a harmonic balance bolt in the end of the crankshaft. But, as other's point out it should stay on by itself. Is the balancer or one of the pulleys warped causing wobble in it as it turns. Without a bolt, I would guess any wobble could cause it to loosen without a bolt but that's a long shot of a guess. They shouldn't come off after they are pressed on.

Edit: A caution if you add a harmonic balancer bolt, DO NOT use it to install the balancer as you run the risk of stripping the bolt. Use a harmonic balancer tool. Also, do not drive it on with a hammer as that can drive the crankshaft back against the main bearings.

 

[Chasefamily]

 

[Chasefamily]

The pulley above it does have a slight wobble and sounds like bearings are going bad. Any idea where I could get the best deal on both of those parts? Seems to me it may be best to just replace them? Thanks in advance for all the help!

 

[Rick Stephens]

All the black stuff looks like belt particles. Good time to replace things. As noted, never use a block and hammer to drive the pulley on, you will damage the crank bearings.

Those parts are identical to what comes on the motor from Chevy. Don't buy Mercruiser replacements parts and pay 3 or 5 times more.

 

[Alumarine]

The pulley above it does have a slight wobble and sounds like bearings are going bad. Any idea where I could get the best deal on both of those parts? Seems to me it may be best to just replace them? Thanks in advance for all the help

The pulley above it doesn't have bearings but what it attaches to might.
I think it's the water pump. You have to find out why it's wobbling.

You can get the balancer from an auto parts store.
You can try GM #'s 03826280 or 3826280 or 03826292 and see if those match up.

 

[Chasefamily]

The pulley above it doesn't have bearings but what it attaches to might.
I think it's the water pump. You have to find out why it's wobbling.

You can get the balancer from an auto parts store.
You can try GM #'s 03826280 or 3826280 or 03826292 and see if those match up.

 

[Chasefamily]

Not sure what effect it would have but I'm pretty sure I have had the wrong belt on it since I bought it (belt that came with it). I posted pictures of the new belt I got and put on and the old one. After putting the new belt on and putting everything back together she appears to be running as she should!
Also, I took the idler pulley off and there is nothing wrong with it, it was rubbing on something. Cleaned it up and it sounds and lives great.

 

[Chasefamily]