Merc 25H making squealing noises, help!

[EBass]

I have a 1988 25H merc manual start. Last night I noticed when I slowed down this higher pitched squealing sound was coming from my lower unit. At idle it went away. Then went to a different part of the lake and now it's louder and it still squeals at idle and gets louder when I give her gas. I shut her down a used the trolling motor.

My friend thinks it's my water pump. Has anoyone ever heard of this? Could my lower unit be shot? Would that make a different sound?

I'm a first time boat owner and I have no idea.

Please help out if you can.

Thanks,
EBass

[EBass]

I still can't find that hidden bolt under the trim tab. Valv or Surface T, can you describe in great detail on where to get to it?

I have that shallow drive platic plate that props up to trim it up. Is that what you're talking about??

[Surface Tension]

Theres a plastic plug on the top side of the zinc fin on you lower unit. Remove the plug and you'll see a stub with a nut.

[EBass]

Zinc fin? I took off the counter balance thing right above the prop, but you're not talking about that. Valv emailed me some diagrams. I have serial # OB351219. So this isn't found if the prop is off? There's two screws not bolts behind the prop. I would imagine bearings and seals and such.

Zinc fin, zinc fin.. if I was behind the boat looking at the prop it would be...?

Sorry man, I feel like an @ss asking all these Q's.

[Valv]

Eric, no problems, we are here to help, we are all "professional mechanics" and we all know what we are doing, right...

Anyway look at second picture I sent you, it's part # 39 right below cavitation plate.
It has a bolt to hold it from top, when removed it will reveal a bolt underneath (you have to look upward from prop).
As ST said, DO NOT pry it, it's all alluminum and it gets damaged easily, try to shake it, or sometimes, having a friend doing it, tap ignition key to crank motor a fraction, while you hold lower unit from falling.
Don't mess with shift rod or parts above lower unit.

[Surface Tension]

hehe

Yes the fin thats right above the prop.
It balances out props torc. Its zinc to protect your motor from corrosion. Only reason to take the prop off is if it should start your not going to loose any fingers.
The lower unit will separate by the anti- cavitation plate.(big horizontal fin)
No need to pull the prop shaft.(the thing the prop go's on)

[EBass]

#39, ah see now. Just to recap (no internet at home to ask you over the weekend) Remove the four main bolts on the lower unit. (plain as day to see) Also, remove the bolt under the counter balance, then it should slide right out? Nothing

We already messed up. When trying to get it off the first time we switched gears while the lower unit was dropped (about an inch)We did bolt it back on and now it shifts hard and not right. So I'll be messing with that. Now that I said that do you guys have any tricks for simple alignment when putting it back on?

Again thanks for all your help.

[EBass]

Surface Tension, Valv...

I took off part # 39 the counter balance and looked underneath for the bolt. I did not see one. However; I have ran it a few times and no squealing sound anymore!! So the line caused that issue.

Thanks for all your help. Valv with the serial # I posted do I have a different model than what you were thinking?

[EBass]

Bump-a-roo