Slow Water Output 1994 Merc 25

[LandlockedPirate]

I have a new-to-me 1994 Mercury 25 longshaft 2-stroke electric start that I converted from remote to tiller steering. This outboard has barely been used and the seller/original owner said it had been sitting for 3 years. We picked it up out of a horse barn. Needless to say, it was home to a few insects.

Anyway, I muffed it today. She started right up but no water output. The water pump indicator hole and tell-tale hose were both pretty well clogged with mud and debris. I cleaned those out and started it back up. Water was flowing but very little pressure and not a steady stream. Tonight I pulled the thermostat housing. Everything looked to be fine. I then removed the intake vents. No obstructions there either. By the way, the powerhead never got too hot while running. I could always touch it barehanded, which makes me think that the cooling system is somewhat functioning.

I am now stumped. My only thoughts are impeller and/or malfunctioning thermostat. Should I try to run it without the thermostat to see if the flow is greater or would that harm the internals? Should I just get a new impeller and pull the lower unit? I'm looking for something to try tomorrow so I know if I need to order parts come Monday.

Any and all suggestions or ideas are greatly appreciated!

 

[Laddies]

Re: Slow Water Output 1994 Merc 25

In till the thermostat opens the only water at the telltale is from that small notch you may have seen on the thermostat. We have enlarged them for customers that wanted a better flow till warm but it's a normal thing on a hose when underway watch and the flow will increase as the thermostat opens I am sure.

 

[LandlockedPirate]

Re: Slow Water Output 1994 Merc 25

Thank You for the fast response! I'll take it out and keep a close eye on it. Once again, Thanks.