Merc 140hp overheating issue

[lmorefield41]

I took the boat on the Chagrin River (Eastlake, Ohio) on Saturday. Was just taking it easy as it was the first time out. The engine quickly overheated and started to stall. The temp gauge pegged out at 260 degrees+. I'm going to replace the thermostat as well as the impeller. My question is if there's anything else I should replace that could be the source of overheating? Before taking the boat out, I replaced the water intake tube.

Another question I have is if any of you know that type of drive this is? I believe it's a mercruiser r mr alpha one. I want to order a new water pump kit for it but I'm not sure which kit to get.

There's this kind by teleflex marine 18-3517

Then there's this kind by mercruiser (mercury) 817275T 4

 

[Bt Doctur]

Re: Merc 140hp overheating issue

Appears to be the Alpha drive with a whale tail, 18-3817 pump kit.
Before you just start replacing, check the oil. You may have popped the head gasket. In the future try not to operate over 175 degrees, stop and get a tow.
Why did you replace the inlet tube, the one in the drive itself or the water inlet tube for the water hose in the transom?

 

[lmorefield41]

Re: Merc 140hp overheating issue

The water inlet tube for the hose in the transom, I replaced the lower shift cable and decided to go with all new bellows, and the inlet tube as well. As far as checking the oil, is that the oil in the engine? Or the gear lube in the drive? And what am I checking for, the level? Also, is there a way to tell if the gasket is toast without removing the head?

 

[stonyloam]

Re: Merc 140hp overheating issue

The water inlet tube for the hose in the transom,

Wild guess: You kinked that hose, easy to do. Check your rubber engine exhaust bellows (between exhaust elbow and exhaust pipe inside boat) and your exhaust shutter is probably shot. Both due to lack of cooling water in exhaust.

 

[achris]

Re: Merc 140hp overheating issue

Wild guess: You kinked that hose, easy to do. Check your rubber engine exhaust bellows (between exhaust elbow and exhaust pipe inside boat) and your exhaust shutter is probably shot. Both due to lack of cooling water in exhaust.

and you're probably cooked the water pocket cover too... Bad news on those drives...

http://forums.iboats.com/showthread.php?t=556903&p=3825409&viewfull=1#post3825409

Chris......

 

[Grub54891]

Re: Merc 140hp overheating issue

And you should not use that silicone on the gasket,it should seal properly installed dry!Mabe you got silicone inside the pickup,and it went into the motor/thermostat.

 

[lmorefield41]

Re: Merc 140hp overheating issue

This is more than likely the culprit behind the overheating

Wild guess: You kinked that hose, easy to do. Check your rubber engine exhaust bellows (between exhaust elbow and exhaust pipe inside boat) and your exhaust shutter is probably shot. Both due to lack of cooling water in exhaust.

The hose isn't kinked, I checked it and contorted it in every angle that the steering and trim would allow right after I installed it. I checked again tonight. It's good. I also replaced the exhaust shutter Saturday with a brand new one before I went out, as the old one was beat beyond use. It's also good.

and you're probably cooked the water pocket cover too... Bad news on those drives...

http://forums.iboats.com/showthread.php?t=556903&p=3825409&viewfull=1#post3825409

Chris......

I read from the link, When I was out Saturday, I gave it no throttle, just shifted and trolled around the river for all of 30 minutes. It was my first time on the water since the restoration so I didn't want to get ahead of myself, and I'm glad I didn't. The water tube that is connected to the water pump housing, the removable tube, is melted, it'll be replaced with the new kit.

My next question is how do I check for the rubber pieces stuck in the cooling passage? I'm sure they're bunched up ready to block water even after installing the new impeller.

 

[achris]

Re: Merc 140hp overheating issue

And that housing is trash too... It's been heated and the cup has slid. See the gap at the back of the housing (near the top of the photo you posted)? Shouldn't be there... Throw the whole thing away and start with a new everything, including the base and plates....

Chris.........
(good photo btw)

 

[lmorefield41]

Re: Merc 140hp overheating issue

Will do, going to pick up the parts in the morning from the local marina. Thanks!