2005 25hp Tohatsu 2 stroke stop peeing at higher rpm.

[hookedontail]

At idle the motor pee's but seems alittle weak in my opinion (dont know if thats normal or not). When I am running at a higher rpm about 50% throttle or more, the motor will pee for a while and then I will look back and notice it stopped completely. There will be alot of steam coming out of the upper exhaust tubes and it will stall or I shut it down. While I am running though it seems like the stream is strong and steady (still not as strong as a yami I have noticed) and then it's like it just quits. After about an hour or so to let it cool I start it back up and it pee's again. Now that I know it does this, I watch and the second it stops peeing I shutdown the motor. First I thought it was clogged but couldnt find anything each time. I figured my water pump needs changed but I am wondering if there could be anything else before I start ripping it apart. I was told the the gasket has been changed to the 30hp gasket between the carb when I bought it and I did not know if that has anything to do with it. The motor runs like scalded dog. Any advice on this would be greatly appreciated.

Thanks
J

 

[pvanv]

Re: 2005 25hp Tohatsu 2 stroke stop peeing at higher rpm.

If it's been a couple of years since the wp was serviced, get a new kit (not just the impeller!), and freshen the pump. While you have the LU off, blow both ways through the cooling system to verify nothing is stuck in the block or the water pipe. In a worst-case scenario, you could have a chunk of impeller vane jammed in the cooling system, which floats and flops around, causing intermittent flow.

 

[hookedontail]

Re: 2005 25hp Tohatsu 2 stroke stop peeing at higher rpm.

Thanks pvanv. Do you think the housing would need to be replaced due to it getting over heated. The gentleman at the marine repair/store said it might be warped as well from the heat. I know he might be trying to get me to buy more parts. Does that sound right to you? I just want to make sure while I have apart. Plus it's a $36 part and a 45 minute to an hour drive. It's funny...... I can rip a turbine powered helicopter to pieces and put back together with no problems but dont know a darn thing about these little engines yet!

 

[pvanv]

Re: 2005 25hp Tohatsu 2 stroke stop peeing at higher rpm.

If the pump has always been submerged, even if it's got a bad impeller, it's not likely to get overheated (though the motor will, due to lack of water circulating). Now then... IF the motor was run out of the water (or a plastic bag wrapped around the intake), the wp would definitely overheat, and that often does melt/distort the upper wp housing. If your leg was steaming, it did overheat... but if the overheat was confined to the powerhead, you are probably OK.

Drop the LU and pull the pump apart before you make the trip to the dealer. That way, you can inspect the pump housing for any distortion, and if you need the upper housing, pick it up while getting the wp kit. At 7 years of age, you should also closely inspect the LU lube for any possible water contamination. While the LU is down to repair the pump, it's a convenient time to replace the seals in the LU. If the wp did severely overheat, that could hurt the driveshaft seal in the LU, leading to water getting in.

 

[hookedontail]

Re: 2005 25hp Tohatsu 2 stroke stop peeing at higher rpm.

When I get back in town, that is the first thing I am going to do is pull the LU. I really appreciate the advice on all this. I have a really strong feeling the housing is done for also though. Knowing how mechanical things work together, I will bet. I already had in mind of replacing all the seals while I got it open. I changed the LU oil about 3 months ago and only probably put 8-12 hours on it. When I drained it the it wasn't milky and no water, the oil just looked a little worn out. It wont be awhile till I get back to the states but I will definitely post the results to this madness. Thanks again for the help!

J

 

[Sea Rider]

Re: 2005 25hp Tohatsu 2 stroke stop peeing at higher rpm.

After replacing parts recommended by Paul, re torque head gasket to 30 NM with torque wrench, generally you warp head when you been rurring at speed and anything clogs tail water intakes, engines bogs down and stops caput, in that particular case engine will smoke like an indian. If engine starts to miss at higher revs probably new head gasket change is mandatory if wanting that horse to run as a champ.

If impeller vanes went already into engine causing water peeing intermittence will need to go find them. Start by removing thermostat, take advantage to check it's condition, replace if excesively salty/corroded. If not there will need to make extensive search and parts, lids that deals with water passages be removed to careful inspect.

Happy Boating