am I overheating??

[oxbeast1210]

1955 fastwin 3hp

Hello i was wondering if anyone knows what temperature this motor is supposed to run at ? i replaced the impeller and cleaned out the water passages completely water sprays out of the little holes where it needs to . but i still cant keep my hand on the head very long probly about 2 seconds when i checked it with my laser thermometer it would stay right around 175 degrees at idle is that to hot?
thanks guys

 

[Rick.]

Re: am I overheating??

I guess that depends on where your pointing your laser but off hand I would say your overheating. At the top of the head it should be not more than 140F. If it has no thermostat then I would think cooler than that even. Make sure you have it well into your water barrel. The higher the water level the better. Best of luck. Rick.

 

[oxbeast1210]

Re: am I overheating??

Thanks rick how far up is the minimum it has to be in the barrrel?

 

[oxbeast1210]

Re: am I overheating??

Hey guys I'm out of ideas on how to make this motor run cooler does anyone have any suggestions? would the wrong spark plugs cause it to overheat?
I want to fully restore this motor but not until i can get it to run at normal temperature.

 

[kfa4303]

Re: am I overheating??

Hey Ox. First of all, you want to fill the water in your barrell up to just an inch or so below your main exhast port. Check the temp as soon as you see water/mist come out of the exhaust port, then check again a few minutes later to compare. Your exhaust water may be a bit warmer than it should b/c your motor recycles the same warmed tank water over and over. The best way to check would be on the open water where you can draw fresh water constantly, if it's still too hot (over 140), then start with simple stuff first, correct temp spark plug, good, thermostat (if there is one), waterpump(impeller) and correct fuel oil mix. If there is too little oil in your mix that can make yor run lean and hot too. What mix are you using now? Most folks suggest 24:1 for that vintage motor. Thankfully, those are all pretty simple things to check before your get more involved. hope it helps.

 

[oxbeast1210]

Re: am I overheating??

thank you for your very helpful advice! currently im running 24:1 ratio on the fuel/oil mix. the impeller is new i just replaced it . there is no thermostats .
the only thing im unsure of is the spark plugs im going to see if i can find out what the correct ones are
thanks alot!

 

[lindy46]

Re: am I overheating??

My experience has been that those little 3hp motors run hotter than the larger motors. If you cleaned the passages and it's spraying water out the holes in the leg, you're probably ok to go.

 

[kfa4303]

Re: am I overheating??

I agree. Gotta remember it's 55 yrs old too, so a bit of warm exhaust probably not a big deal.

 

[oxbeast1210]

Re: am I overheating??

Ok cool ima go ahead and use it as is its staying at 160 degrees now that i raised the water so i think good to go thanks for the advice now i gotta find the decals

 

[seahorse5]

Re: am I overheating??

measure the temp at the cylinder walls, not on the cylinder head because there is very little cooling water around it. The head gets very hot normally and will burn your fingers.

Just be sure the cooling passageways are clear in the block and exhaust area as salt deposits or mud can build up quickly and restrict water flow because they are so small and make right-angle bends.

 

[oxbeast1210]

Re: am I overheating??

thank you seahorse that makes perfect sense now! the heads are what i was measuring the walls are at 145 degrees

 

[Lostfisher]

Re: am I overheating??

I was having the same problem on a little 3 hp from 58. I changed the impellar, took the powerhead off +cleaned out all the passages filled my running tank up all the way it never managed to cool down. I just made up my mind and decided that that was the bes that the motor was going to run.