Force 50hp--not cooling

[rngadng]

1988 Force 50hp. I just bought the motor and I am have problems with it cooling. Overheats at idle. Re: the cooling system, the impeller works, the pump works, and the water jacket around the powerhead is clear, but there is blockage [I think] from the lower unit up to the powerhead. I tried blowing air from the powerhead back down to the lower unit without luck (perhaps a baffle blocks this reverse track?).<br />Any assessment of the problem, or how to clear the blockage. Maybe it is not blockage and I have another problem? Thanks in advance

 

[Yepblaze]

Re: Force 50hp--not cooling

What are you using to determine that it is actually overheating?

 

[rngadng]

Re: Force 50hp--not cooling

re: how we knew it was overheating (forgive the novice terms that follow), but block of the powerhead was hotter than hell, it was smoking and the smell of burned rubber was present. At that point we shut it down. <br />More info: <br />1, prior to putting it in the water, we used e-muffs and a hose, and did not see any telltale water. Reading this site, indicates that Force 50hp from late '80s, do not have telltale, rather a mist/steam from the exhaust hole--which we did have once we put it in the water. <br />2. Prior to putting into the water, the theremostat had been removed and not replaced.<br />2. When idling in the water, there was no water in the powerhead waterjacket, as evidenced by removing the plug located in front of the theremostat housing on the block.<br />3. Again, impeller seemed fine, pump was fine, but no water was making into the powerhead water jacket.

 

[kmb]

Re: Force 50hp--not cooling

Hey Bob, I have a force 50 and recently had a similar problem. Now keep in mind I am by no means an expert: my problem was that there is a copper pipe that goes down to the lower unit from the powerhead. I took the lower unit off after I had the same syptoms and found a black piece of plastic that felt like shrink wrap inside where the pipe goes into the pump. It was blocking the water flow and removing it solved the problem. Maybe your problem is also that simple?

 

[oldboat1]

Re: Force 50hp--not cooling

The water probably comes up through the exhaust port, then to the head and back out. There can be a blockage in the exhaust port water passages as well as the cylinder head. For a direct check, you can remove the exhaust port cover (probably about 8 screws on the side of the powerhead) and look -- and prod and poke. Another approach would be to drop the lower unit and try to force water or air up through the water tube. You should be able to do the latter (thermostat out) unless there is indeed a blockage. I just worked on a Chrysler I use as an auxiliary, and had the head and exhaust port cover off, forcing water in from each point and from the water tube -- but it cleared the blockage.<br /><br />I don't have any doubt from your description that the engine is overheating.<br /><br />(so what's the name of that little snack shop on Reeds Lake -- and did it ever sell?)

 

[Franki]

Re: Force 50hp--not cooling

If your paint was smoking and it smelled like burning rubber, you may well have done some damage to your motor.. at the very least you have probably lost some compression due to the rings getting to hot and losing tension.<br /><br />don't spend to much time with the engine running trying to work this one out.. you'll only make it worse..<br /><br />your engine should never get so hot that you can't touch the head for about 4 or 5 seconds.<br /><br />drop off the lower unit, and see if you can use a hose to run water through the motor by putting the hose on the pipe running down the leg.. see if it gets through the system. (take your water jacket plug out and see if water is getting through.)<br /><br />If it does, then the problem is most likely in the pump region...<br /><br />how do you know the impeller is good? have you replaced it recently? an old one can look good and not be.. so replace it..<br /><br />regards<br /><br />frank

 

[oldboat1]

Re: Force 50hp--not cooling

another thought -- blockage could be at or in the exhaust ports on the back of the leg. You might be seeing some exhaust but there should be a pretty good supply of water coming out of there. The smoke you saw coming up might have been exhaust -- although it's pretty clear you are overheating.<br /><br />On that Chrysler I referred to earlier (older and smaller brother to your motor), there was a mouse nest blocking everything up. I had a devil of a time getting it all out, but did so by disassembling and flushing.<br /><br />As Frank indicates, it still isn't altogether clear that your impeller is doing the job, so that should definitely be checked.

 

[rngadng]

Re: Force 50hp--not cooling

Gents:<br />Thank you for you time in replying and we will undertake these steps (however, all others please feel free to chime in with ideas).<br /><br />Frank: I hope that I have not done too much damage to the engine already. We shut it down when it was apparent something was amiss. **** the luck, when we saw the spray from the exhaust holes we thought we were in good shape.<br /> <br />Oldboat1: Rosie's Diner, as it was originally named is still called "Rosie's", but it is a nice restaurant now, no longer a diner. Don't go there often as we're north of GR proper, in Rockford on another inland lake.<br />RJN

 

[oldboat1]

Re: Force 50hp--not cooling

Rosie's. That was it. Sounds like it's now gone the way of hanging ferns and stainless steel. I guess that was thought to be the best use of expensive real estate.<br /><br />Good luck with the motor. If there was indeed some water coming out of the exhaust ports on the leg, that tells you that the impeller is at least working some -- and some water may have also gotten to the head. Hey -- optimism.<br /><br /> Curt (olboat1)

 

[revertmastec]

Re: Force 50hp--not cooling

Bob,<br /><br /> Once you clear this problem I would highly recommend you installing a temp gauge. Takes the guessing out of whether you are getting to hot or not.