Jet Pee question

[kkrueger]

I bought a used Mercury 40/30 jet this week. It is a 2000 model (I believe) that has been meticulously maintained. I ran it today for the first time. Hooked to the hose it pee's really good. Moving down the lake it pee's really good, at idle it is just dribbling. I know next to nothing about a jet, but my prop motors all pee much better at any rpm. Does this need a new impeller, or when I sit still idling is it not deep enough to pick up water???? Hoping to hit a river tomorrow, but staying home beats overheating.

 

[jbnelson]

I have that motor a1995 model and it does the same thing. It sometimes helps to run a piece of trimmer string or anything that fits into the pee tube to clean it out. I have been slacking on replacing the impeller but I have not had any issues with overheating. I also don't idle very long. Hope you get to try out.

 

[dhoganjr]

+1 on the trimmer string or anything that will fit. I keep a section of 16 guage wire about 3 ft long to run through it in the boat. The water pump pulls water from ports inside the main pump housing above the impeller(auger). So as long as the jet pump is loading, shooting water out the back nozzle, it doesn't matter how deep in the water the jet pump is. The telltale indicator (pee-hole) on jets are a pain because you are skimming the water surface like a huge vacuum sucking up all sorts of debris, (twigs, leaves, rocks, etc). Most shoot out the back, some go through the cooling system and get stuck. Hook the hose up, pull the cover off and follow the line from the pisser, check any fittings and connectors. Take them apart and check for debris also behind the thermostat. Flush it all, put back together and run it.

Enjoy it!!! Report back. Pics?

 

[kkrueger]

Thanks, I feel better now. I fished sat eve and idled as little as possible. Try to add some pics soon.

 

[JoshKeller]

thermostat opening and closing? on my old 94 merc 25, the tell tale pressure was varied depending on the engine temp. cold engine was just a dribble, when the thermostat opened it was like a water hose - it would go between the two until you were under way and the motor was turning some rpm.


id set it in a barrel or on the hose and let it idle 5- 10 minutes. use an infrared temp gun to even your hand to tell if its overheating.

 

[user 6672]

Regardless of how well you think it was taken care of id throw a new water impeller in it.

 

[huntinfool]

Regardless of how well you think it was taken care of id throw a new water impeller in it.

Agree, a new impeller is cheap compared to a new power head. Besides the one in there now may be I'm backwards.

 

[benagy]

I also just purchased a 2000 Mercury 60 45 Jet, and it did not "pee" very well. The fellow I bought it from told me it had the impeller replaced in 2006. I have the service manual, and decided to change it myself.

It was pretty easy, as there are 6 bolts to take off the grate, one for the thrust impeller, and 4 that hold on the pump. I got the gasket, impeller, and a new rubber coupling. In my case the rubber coupling was bent over and blocked the flow. You have to be careful, as it is easy to get it misaligned.

All in all it took an afternoon with a buddy, and it now has a strong outflow.

I saw you are in McDonough, GA, I am in Gainesville. Drop me a note if I can help.

Bert