1996 Mercruiser 4.3 electrical issue?

[Maclin]

I did not realize you only had it running for a very short time after the "incident" . Fuel bowl contents will let it idle under load for minutes perhaps.

 

[Swedefj40]

Yeah it was real quick, I doubt it ran for more than 10 seconds.

 

[Swedefj40]

So I got the new oil pressure switch (PN 87-864252A01) and sender (PN 8M0068784) installed and I now have oil pressure. It was cold and showing 50 - 60 psi. It didn't budge much even with it idling but then it wasn't warmed up either. I still noticed the vibration and it was minor at idle but more pronounced with revs. I also noticed what looks like a harmonic balancer really out of balance looking. Looked like it was varying about 1/4". Is there a possibility that this has failed or that it's compensating for the vibration? Oh and the Tach is still not reading properly.

 

[alldodge]

If the balancer is wobbling, then it needs replaced

 

[greno]

Sounds like you could have spun a coupler. I would suspect that before something like the harmonic balancer. I've seen harmonic balancers look wobbly from people using a puller the wrong way to try and get them off. It doesn't change their balance but pulls them crooked.

 

[Swedefj40]

"Spun a coupler" what do you mean? I'm not familiar with the coupler?

 

[greno]

Between the engine and the outdrive there is a rubber device known as a coupler that transmit the engine torque. It is a flex type coupling. These are a maintenance item and they will all eventually need replaced at some point. And they do give off a smell when they fail.

 

[Swedefj40]

Oh okay...

Here's a vid on the Harmonic Balancer

 

[nola mike]

These are a maintenance item and they will all eventually need replaced at some point.

That's like saying the engine is a maintenance item that will eventually need to be replaced. Couplers usually fail because of user error. And they don't *kinda* fail. Anyway, YouTube tells me the vid is unavailable

 

[greno]

Couplers usually fail "early" due to user error. But they will all fail eventually. I've put 3 in my 41 year old craft that gets alignment checked regularly. So about 14 yrs is what I get out of them.

 

[Swedefj40]

YouTube tells me the vid is unavailable

Sorry... I had it as private... try it now.

 

[greno]

Yeah, that harmonic balancer is bad. It's not wobbling. It's out of round. Replace it.

 

[Swedefj40]

Got the pulleys off but the balancer is fighting me big time (yes I removed the bolt)

 

[greno]

That one looks pretty bad. Why so much rust on this engine? Was this boat ever sunk?
Anyway, PB Blaster and heat is how you get ones like this off.
Be real careful using a torch in the boat. Lots of flammable stuff around.
I use a welding blanket to shield things.

 

[Swedefj40]

That one looks pretty bad. Why so much rust on this engine? Was this boat ever sunk?
Anyway, PB Blaster and heat is how you get ones like this off.
Be real careful using a torch in the boat. Lots of flammable stuff around.
I use a welding blanket to shield things.

No idea if it was ever sunk, but it's spent it's entire 22 years on the coast here in BC so it'll have some rust.

As for the heat thing, I am thinking the same thing. The fuel tank is right in front of the engine too so I'll be taking all the precautions I can.

 

[Swedefj40]

Anyone know where the tach gets it's input signal from?

 

[greno]

The tach signal usually comes from the distributor or coil.

 

[Scott Danforth]

Got the pulleys off but the balancer is fighting me big time (yes I removed the bolt)

spray penetrating oil on the crank, in the balancer hub. apply pressure with puller, repeat.....then smack the balancer hub with a big hammer. it should start to pull off.

 

[greno]

... then smack the balancer hub with a big hammer.

Please don't ever do this. You can cause internal engine damage by doing this.
All you need is some heat and penetrating oil and a proper damper puller.

 

[Swedefj40]

Been working at it... Been trying to smack it with a brass hammer but I can't get much force on it due to the location. Not a lot of room down there. Soaked it good last night with WD40 with the puller cranked down and left it over night and did it again this morning before work. Hopefully it'll release tonight.