R3 overheating.

(R3, R5, R7, R30, R35)
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bruceb58
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Re: R3 overheating.

Post by bruceb58 »

Put your flush hose on and remove the hose on the intake to the pump...does water come out?

If it does, remove the hose from the pump that goes to your heat exchanger...remove at heat exchanger. Start engine and see if water is reaching heat exchanger.

BTW...put your engine/drive type in your signature.
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Re: R3 overheating.

Post by Bean »

Flushed intake hose from raw water pump. Water came out intake holes. Flushed other hose and water came out where it should at transom. Still runs fine with flush hose. Hoses look fine all the way to the transom. I conclude the hose in with the trim pump was disturbed and water is coming out but not in through it. Maybe a loose clamp. Dealer wants nothing to do with me. Probably backed up for months. Can I get in there?
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billk2632
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Re: R3 overheating.

Post by billk2632 »

Yes, by tilting and turning the drive you should be able to get to the hose clamps - it's tight and you will need some socket extensions and swivel, but should be able to get in there and tighten things. My bet now is one of them is loose and the pump is sucking air. Also, the plastic pieces on the pickups, lower part of drive? Would not hurt to pull those off and check for debris.
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Re: R3 overheating.

Post by Bean »

I can see the big hose from the transom to the unit and it is fine. It's the inside that I can't get at that I'm worried about. I don't want to start taking things apart that I may not get back together again.
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Re: R3 overheating.

Post by billk2632 »

The other piece of that hose is outside the boat, connects from the transom assembly to the bell housing. A loose clamp anywhere in that hose could cause it to suck air. I doubt they would have messed with that hose on the inside of the boat, it would have been outside. Did they take the drive off to do any of this work?
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Re: R3 overheating.

Post by Bean »

I don't know. Where is the trim pump?
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Re: R3 overheating.

Post by ajcampen »

Time to find a mechanic. See if they will let you watch
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Re: R3 overheating.

Post by billk2632 »

Bean wrote: Fri May 19, 2023 5:44 am I don't know. Where is the trim pump?
Trim pump is mounted on the transom assembly, STB side outside the boat. Lower right side of transom assembly - this is a picture of mine.
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Re: R3 overheating.

Post by Bean »

Thanks all.
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bruceb58
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Re: R3 overheating.

Post by bruceb58 »

If the boat overheats while just running and not on plane, none of the connections on the drive really mater since the drive is submerged.
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Re: R3 overheating.

Post by Bean »

First time I couldn't fix something myself. The dealer had it for two weeks and was baffled as well and finally found a small crack in the raw water pump. It was pumping but not enough. New pump all better. Thanks for all your suggestions. I may need you again.
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Re: R3 overheating.

Post by kas232ca »

Great they found it!
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Re: R3 overheating.

Post by billk2632 »

The water pump housing was cracked? Wow - so the pump must have been sucking air through the crack -- we knew it had to be sucking air from somewhere, just would not have figured the pump housing.
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