View Full Version : GLamb

05-08-2009, 06:32 PM
working on a 87 Force 50 hp. A model

i can't find anything in my manual with temperatures. do you know what the operating temp should be on this motor? and at what temp. is it overheating? motor runs at about 200 and this seems to hot to me. Thanks George

05-08-2009, 07:06 PM
"George, I also have a 87 Force 50 hp. and it has a thermostat on the top of the powerhead. My manual does not tell the tempature, however I think it should be about 165 deg. The part number is 97068-2 for the correct stat. I replaced mine and retrofitted the powerhead with a pee pipe. I would also replace the thermostat spring and washer at the same time. I have the additional part numbers if you need them, but you can go on line to Crowley Marine and download the parts breakdown if you need to."

05-08-2009, 07:12 PM
"As far as a high temp, you should have a high temp alarm horn under the control area of the boat. The sending unit in the head, should be Red in color acording to the service manual, which has a higher alarm point. However it does not give an actual tempature. Maybe some one else has the exact temps you ask for."

05-09-2009, 04:56 AM
"I have changed the thermostat and it runs about two hundred with or without it in. the overheat sensor is no good and they don't make them any more so i have a temp gauge on it now, that is how i know it runs about two hundred, but what i don't know is how hot they can run safely, already rebuilt the water pump and checked all the lines. i can run it in the driveway with muffs for 30-40 min. and it only gets to 100, but as soon as it is in the water and starts to run it jumps to 200.
compression is good, 130, and the leak down test looks good, timing is right"

05-09-2009, 10:34 AM
"Further checking into my manual, has a section for testing the alarm sender. The sender should close and alarm btwn. 180 and 200 deg. The sender should open and silence btwn. 160 and 180 deg. Thats acording to my SELOC manual. So if in fact your temp is an actual 200 deg. you have a problem. Symptoms of overheating are loss of power, pinging, a burning smell or powerhead paint discoloration. Could be caused by, fuel system problem causing lean mixture, oil/fuel mixture to lean, or incorrect spark plugs. Other than that, I don't hav a clue."

05-10-2009, 05:25 PM
"okay, this is grasping for straws... but i am out of ideas. are there going to be different numbers for water temp. and cyl. head temp.? looking at the t-stat it is measuring the water temp and where it is coming into the motor, along with the heat sensor, checking water temp at the top of the motor where the water comes in. my temp. gauge is measureing cyl. head temp and i have it connected between the two cyl. and i know that the bottom cyl. usually runs hotter than the top one, further from the cool water coming into the motor. so now i am wondering, is the temp that i am looking at going to be higher than the water temp numbers i am comparing them to for a normal operating temp.?? if not, do you have any suggestions what i should look at next... heat range on the plugs hasn't changed, the plugs burn clean but aren't white or light gray like it is to lean, the fuel-oil mixture is always exactly the same. there is nothing to indicate that there is an air leak, leak down test shows top of the good range. there is no way to test the water pressure , but the impeller is new and there is water coming out of the tell tale. i'm stumped??"

05-11-2009, 03:12 PM
"Just some additional information, I found a new high temp alarm sender at www.boaterslandfishing.com (""), Pt# 817939A1 but you will not like the price. Just look up the parts section for your motor."

05-24-2009, 04:00 AM
"I hate when poople don't follow up, especially after trying to help them, not knowing what was needed or if you are looking for answers for something simlar, so... my suspecian was right, the cylinder head temp will be 20 to 30 deg. hotter than the water temp. i moved the sending unit for the temp gauge to the same location as the t-stat and the over heating sending unit and now the gauge reads 160.
hopw rhia helps anyone with the same problem, and thanks to all those who tried to help. george"