1988 force 85 no cooling

[jeffisjacked]

I have a force 85 hp with a strange cooling issue. I wasnt getting any water at all out the two exhaust ports on the back and the over heat alarm goes off within a minute. I checked the thermostat (110 degrees) and it didnt open even in boiling water. I took it out completely and tried again, same issue. I changed the impeller and housing but i still have the same problem. I blew air through the water tube and it comes out fine through the exhaust ports. Ive done this with muffs and with the lower unit in a tub of water. I took the lower unit off and put muffs on it but no water comes out the top of the pump. Should it be? what am i missing??

 

[john from md]

Re: 1988 force 85 no cooling

Take the pump impeller out and try the muffs. For some reason, muffs do not get water up without the pump turning.

When you pull the impeller, make sure that the woodruff key was in place. Without the key, the pump won't turn.

John

 

[jeffisjacked]

Re: 1988 force 85 no cooling

completely out? should i take the gasket and plate out as well?
I just took the pump apart and put it back together spinning the shaft clockwise per my manual....i get water coming out the spout at the bottom, but still nothing to the thermostat or out the two ports.I blew everything out with air once more to check for clogs, still nothing. what the heck am i missing?

 

[RRitt]

Re: 1988 force 85 no cooling

{deleted} same as john

 

[jeffisjacked]

Re: 1988 force 85 no cooling

i also dont understand what running the the motor with no pump is supposed to accomplish.

 

[jeffisjacked]

Re: 1988 force 85 no cooling

I am adding a tell tale tomorrow to ensure im not a complete moron, but im not getting anything as of yet through the two ports.

 

[sillyocis]

Re: 1988 force 85 no cooling

i feel your pain brother. i have 86 force 85 and have been battling similar issues. i pulled the lower unit after adding a telltale that would not flow water at all. everything appeared okay much to my dismay. then i even tried filling the water pump housing through the telltale to "prime" the water pump and still nothing. the only difference in our stories is that my overheat alarm has never gone off probably because iv'e never run the motor for very long knowing that water was not flowing. i get spittle out of the two exhaust vent holes but thats it. impeller looks great. i just dont get it. hopefully someone has answers for us. im ready to replace every seal and gasket just to rule that out and it all looks brand spankin new already. (new boat to me) have no history on motor. good luck to both of us.

 

[sillyocis]

Re: 1988 force 85 no cooling

also. i beleive the impeller has to be out to check passage between the water intake and the tube that bring water up to the heads. if the impeller is not spinning this passage is blocked. without the impeller there the passage will be free and clear and you can determine that your impeller is not spinning. i will try the same myself. maybe the "key" has stripped the inside of the impeller groove even though it looked okay to me. correct me if im wrong john.

 

[john from md]

Re: 1988 force 85 no cooling

In order to troubleshoot properly, you need to have a base line. In this case, you need to determine two things. 1, do you have a clear line to the pump and 2, is the woodruff key missing or damaged.

Unfortunately you need to remove the pump housing and impeller to do this. If you installed the gasket with RTV, try this. Dislodge a corner of the housing and, using a single edge razor blade, skim around under it to cut the RTV and not the gasket. If you cut the gasket, no sweat, just use RTV to reseal the housing. The pressure in this area is only 1.5 pounds.

Sand and debris get packed in the passageway from the inlet ports to the pump from people running into shallow water or rivers that have the bottom stirred up.

One other thing to check for. With the impeller in place on the shaft and the key inserted, hold the shaft and try to turn the impeller. You want to ensure that the rubber impeller is not turning on the bronze insert that sits on the shaft.

Let me know what you find.

John

 

[Frank Acampora]

Re: 1988 force 85 no cooling

Why did you replace the pump housing? Was It heavily corroded?

A heavily corroded pump housing will indicate that the bottom torpedo shaped gearcase seal plate which is also the bottom portion of the pump will also be corroded. This is the plate that the 4 water pump sbolts go through and it is also held onto the lower unit with three other 7/16 head bolts; two in the rear and one in the front.

If the walls between the two sides and around the shaft (under the stainless steel plate) are corroded to the point where the gasket will not seal them, the pump will recirculate a good portion of the water back from outlet to inlet. Pressure will be way down and water may not reach the top of the block.

If the rear of this plate is bent, corroded, or has a sizeable nick in it where the water inlet chamber is, it will suck air and the pump will not function at full efficiency.

Replacement of this plate and the seals is required in this case.