Serious overheating issue. Help appreciated.

lukeb83

Seaman
Joined
Feb 19, 2012
Messages
73
My boat (an 86 larson with a 3.0 140hp mercruiser with alpha 1 outdrive) had an overheating issue the last time i took my boat out last season. I took the boat to a local marina to have them address the issue because i didnt have the time. they told me they winterized the boat, but were too backlogged to fix the overheating issue.
i took the boat out and pulled the lower unit to check the impeller and was very suprised at what i found. the ringing of a cash register in my head hasnt stopped since.

1) this is the impeller housing. it appears to be covered in melted plastic. i think it is the old plastic tube that comes with the kit that connects the housing to the cooling system.
Housing.jpg

2) this is the impeller. its absolutely shot. melted and the fins are pretty much gone.
0426131824.jpg

3) This is what really shocked me. i cant find the name of this "hose" but my best guess is its linked to the exhaust? its located underneath the hose that holds the drive shaft and knuckle coming from the motor. It is COMPLETELY burnt out. i mean gone.
Hose.jpg

My question is, is this typical? i knew the boat overheated some but it did not smoke or anything like that. it didnt even peg hot on the gauge. what is the name of this "Hose"? is it likely i did damage to my motor? how would i check? How is it possible the marina did not notice this hose completely burnt out? is it possible this happened at the marina? thanks alot for you input ahead of time guys.
 
Joined
Mar 27, 2010
Messages
3,008
Re: Serious overheating issue. Help appreciated.

Hi, welcome aboard, unfortunately those pictures are so tiny I can't make out what I see... but will take your word for it.... and I'm 36... the wiser, experienced marine mechanics on here.... are older and more experienced than I and most likely have tougher vision than I do so.... if there's any way you can enlarge those pictures it will help your responses out big time!!

You will definitely need a complete water pump kit.. complete with the housing and lower housing. It ran without water it seems, one way or the other.

The other guy will chime in with their help as well.

Good luck!
 

lukeb83

Seaman
Joined
Feb 19, 2012
Messages
73
Re: Serious overheating issue. Help appreciated.

Thanks Eric. I have the kit and the lower unit pulled off i just have to reassemble it. Here are some Blown up versions of the pics, the resolution is shoddy because i took them with my phone. sorry.

Heres the pics blown up in the same order

LARGE HOUSING.jpg

Impeller Large.jpg

LARGE HOSE.jpg

The last pic is of the burnt out hose. i cant find a part number or even a name for it.
 

lukeb83

Seaman
Joined
Feb 19, 2012
Messages
73
Re: Serious overheating issue. Help appreciated.

in the picture of the hose, the top right hand corner is the back of the outdrive (tilted up) the hose fed from there into the bellows i believe.
its probably 3 inches in diameter (o.d.). the small tubes u can see are actually ribs that were on the hose for expansion.
 

ktbarrentine

Lieutenant
Joined
Dec 12, 2011
Messages
1,296
Re: Serious overheating issue. Help appreciated.

The enlarged pic is still very blurry (maybe it is the vodka and v-8 mango splash I had after work today!)...can't tell if it is the exhaust bellows or the water supply hose from the outdrive through the transom. What diameter is the hose, and can you get it iff enough to take some post-mortum photos?

(edit: Looks like we were typing at the same time, so you gave me the diameter...that is the exhaust bellows... You can replace it to go back to original, or replace it with a sleeve. There are posts on here that describe it.)

From the looks of the severe overheating and the remnants of the impeller/pump housing, I would be very surprised if your water pocket cover (in the upper housing) is not totally melted. And that is a PITA to replace 'cause the bolts like to break off if not done carefully (even IF done carefully, sometimes.) Can you get a photo looking up into the upper half to see the water pocket cover?
 

lukeb83

Seaman
Joined
Feb 19, 2012
Messages
73
Re: Serious overheating issue. Help appreciated.

your 100% correct kt, and your drink sounds delicious. i looked at it earlier. i believe it was 4 bolts holding it in place and it was totally melted. would you recommend pulling the whole drive? it seems that would be easiest. what would you recommend (other than just a standard extension and socket) for pulling these bolts? thanks alot for the input man.
 

ktbarrentine

Lieutenant
Joined
Dec 12, 2011
Messages
1,296
Re: Serious overheating issue. Help appreciated.

Definitely pull the "whole" drive. This work is best done on a bench (besides, you'll want to do your other preventive maintenance with the drive off the boat...don't you?). As for attacking those bolts, I will ask for input from DonS and/or Achris and others who have actually had luck with it. if you snap one of those bolts, it is pretty ugly.

(And the vodka needs to be Three Olives Cake vodka for the best flavor!)
 

lukeb83

Seaman
Joined
Feb 19, 2012
Messages
73
Re: Serious overheating issue. Help appreciated.

kt, i sent u a pm. thanks.
 
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