Mercruiser Bravo 3 Grinding Nose Only When Turning Left

greg82255

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Hi All,

I have a 1994 Formula 252 bowrider with a 7.4 / Bravo III. Recently I have noticed a grinding noise when turning the steering wheel to the left. It very clearly only happens when turning left and nothing else. It doesn't matter the speed, in gear or not, always a noise when turning the wheel left. No matter how far I turn to the left, it grinds the whole time, but even the slightest turn to the right will make the noise go away. Sometimes if I turn very slowly to the left it won't make a noise. I've read similar threads about gimbal bearings and U-Joints going bad, but would think that if those parts were causing the noise, it would be consistent and not when turning left only. Any insight would be really appreciated. Thanks in advance.

Update - here’s a video of the noise.

 
Last edited:

alldodge

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Is the noise coming from the helm or sterndrive?
It makes the noise when idling
If at the helm it might be the rack
If at the sterndrive, then check the power steering ram. Check fluid level
 

greg82255

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It’s definitely coming from inside the engine compartment. It does make the noise when idling and I turn the wheel left. The fluid level was ok last I checked (Monday) but will double check and also confirm exactly where the noise is coming from.
Is there any chance it could be the P/S pump? Don’t want to start throwing parts at it but that one does seem to be pretty cheap for a refurbished model.
 

alldodge

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The pump just pumps fluid in one direction, its the ram that directs it left or right. The pump is the ame as the automotive one, just uses a higher pressure valve which is screwed into the back of it
 

greg82255

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Quick update - I took the boat out today and had a friend turn the wheel while I looked at the engine. The sound is definitely coming from the power steering pump. When you turn left the power steering pump pulley actually slows down as if it can’t turn, the belt slips, and it makes the noise in the video. The pump is pretty cheap so I may start by replacing it. Wondering if there’s something about the pump - maybe a bearing - that is making it struggle or if it is actually the ram or something else.
 

alldodge

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Might need a new belt. If its down inside the V then its worn. Turning to the left requires more power because of the rotation of the prop
 

greg82255

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Might need a new belt. If its down inside the V then its worn. Turning to the left requires more power because of the rotation of the prop
That’s an easy and cheap idea. Will try that first. Thanks!
 

greg82255

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Quick update - bought new belts and a new power steering pump and went out to the boat this past Thursday. Was about to take the pump off and replace and noticed the belt was very very loose - like I wasnt sure how it stayed on. Tightened the belt and the problem went away. Going to return the pump tomorrow.

I replaced the quicksilver belt with a slightly thicker Goodyear belt for added peace of mind. When swapping the belts I noticed The power steering pulley was rusted and a bunch black dust to the left of the engine - so the noise was a rusted pulley grinding against a loose belt when turning left and putting more load on the pump.

One follow up question.. should I consider replacing the rusted pulley? They’re pretty cheap but I dont have the tool to remove/install.
 

alldodge

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Take a wire wheel to it
The tool is $20 at Harbor Freight
 

nola mike

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Also make sure that your pulley is in proper alignment with the balancer and no wobble
 
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