'86 Force 125 ... need cooling help

[PMH]

Hello all!<br /><br />Well, Spring has sprung and its time to start working on the old motor again to get it ready for summer.<br /><br />I've been having a problem with overheating in the upper rpm's. Turns out I've got some blockage in the water cooling system. a local mechanic suggested I check/replace the overflow valve located beneath the exhaust plate on the side of the motor. He said that this valve allows more water to flow through the engine in the upper rpm range. Well, the valve was so clogged up and coroded that I broke it just getting it out. It doesn't look too good inside at all. A ton of corosion and filth.<br /><br />So, can you guys help me map out the water cooling system so I can check for more restricted passages?<br /><br />How can I go about cleaning the water cooling system?<br /><br />Thanks for all your help!<br /><br />Patrick

 

[12Footer]

Re: '86 Force 125 ... need cooling help

I hate to say this, but you'll want to pull the head also.BUT, before going there,<br />I've heard of marinas using an acid of some kind that really does a great job. Don't recall what kind of acid,but it is hooked up to the tstat housing,or flush fitting and pumped-thru the engine for 24 hours. It gets them spotless in most cases, providied it's not a total blockage. You might look into that locally.<br />Also, try a radiator shop,as they may be able to help you with this treatment. It's the same type of acid they use in radiator reconditioning.

 

[PMH]

Re: '86 Force 125 ... need cooling help

Thanks for the reply 12Footer!<br /><br />I pulled the head last summer after I started having problems... gasket needed replacing. I've also replaced impeller and t-stat.<br /><br />And I bought a "do it yourself" acid flush form a boat shop and tried it out last summer. It was called a "de-scaling flush". I mixed it in a large garbage can and then lowered the motor into it. But the directions said to only run acid mixture through the engine for only a minute then let stand for about 5 minutes then flush with clean water. <br /><br />I didn't seem to do anything except make a big mess. <br /><br />But I guess the stuff the pro's use is a bit more potent. I'll look into it!<br /><br />Thanks for the suggestion!<br /><br />12Footer, have you heard of this over-flow valve? The book doesn't say diddly-squat about it. <br /><br />Are there other places in the cooling system that might be prone to getting clogged?<br /><br />Thanks for your help!<br />Patrick

 

[PMH]

Re: '86 Force 125 ... need cooling help

Here's an update:<br /><br />I talked to a repair shop today and they're looking into ordering a new overflow valve. while I had him on the line I asked the guy about this acid flush 12Footer was talking about. His response was "huh?" He said he had never heard of anyone in my area (New Orleans, LA) ever doing such a thing. <br /><br />Tomorrow I'll try a few more local marine shops and if no luck I'll take a shot at the radiator shops. But I'm real hesitant about having someone with no outboard experience tinker with my motor.<br /><br />Thanks everyone!<br /><br />Patrick

 

[cowboyrick7]

Re: '86 Force 125 ... need cooling help

help im new to this forums stulf .but i need help i have a 87 125 force that i just had rebuilt out of pocket 2,850.00 .question is should this motor run a little hot for a few hours everthing thing in the engine is new.i hook up a temp guage and it idls around 180 .when you pull skier it jumps to around 210 but drops down to around 180 .also would be ok to remove termostat for a while till i break in the motor. i have herd that this motor needs water pressure to help cool engine .respond to cowboyrick7@centurytel.net thanks all