9.9 Yami HT kicker over heating

[Rockfish]

Our Yami high thust kicker appears to be over heating. The pisser appears to be working, if not super strong but nothing that would cause great concern. At lower rpm it appears to be cooling adequately but during periods when the infamous JDF current is racing and the kicker has to be run at higher rpm to push through it, it appears to develops symptoms of running hot.

It gets a little white smoke (we don't think it is steam) and you can smell it a little and the head/block feels very hot. I assume it is burning off oil and corrosion resistant spay on the outside of the motor. The motor oil itself is right up and clean. The motor does not get flushed with fresh water all that often compared to motors that are trailered and flushed daily as it stays in the ocean for the season. There is a lot of weed out there recently and we wondered about something being sucked into the cooling system and partially blocking it???

The motor was bought new in Aug of 2014 and does not have a lot of hours on it, but is still on its original water pump. Our plan is to get a new T-stat and water pump/impeller rebuild kit and pull the leg and replace them. Then run the salt away injector system through the motor with fresh water.

I am hoping that fixes it as I really would not like to have to pull the head etc. and clean out all the little tiny cooling passages and miss the end of our very short fishing season this year. May not want to even take that job on ourselves and may have to get a pro to do it, if it is necessary.

Any suggestions or thoughts?

 

[Buckethead905]

Stuck thermostat. Easily repaired.

 

[Rockfish]

Stuck thermostat. Easily repaired.

Had planned to replace the T-stat first and get a good look at it. I have seen a few badly salted up ones over the years. Will still get the water pump kit and have it available.

 

[Buckethead905]

Had planned to replace the T-stat first and get a good look at it. I have seen a few badly salted up ones over the years. Will still get the water pump kit and have it available.

It’s about a 10 minute job from start to finish, I wouldn’t worry too much about the impeller, I’ve seen mains and kickers with a over a thousand hours and still looked new.

 

[Rockfish]

It’s about a 10 minute job from start to finish, I wouldn’t worry too much about the impeller, I’ve seen mains and kickers with a over a thousand hours and still looked new.

Thanks. We have replaced T-Stats before and it should be easy.

 

[profisher]

Get one of the cheap Canadian tire digital infra-red temp sensors. Run it at the speed where you think is getting hot and take a head temp reading. It should be close to the temp rating on the t-stat. I think they are 60C or 140 F...that will be stamped on the t-stat

 

[Rockfish]

As the Yami kicker sits on the outside corner of the Pod, it was not necessary to put the boat on the trailer to work on it. Backing the boat into it's marina slip was all that was necessary to give us full access to replace the t-stat. The motor is now running perfectly. The old T-stat was salted up and had some corrosion. Thanks for the advice.

 

[Daveroo]

Was the T-stat the original from 2014? Just wondering how often people replace them. I had mine replaced a few years ago.

 

[Rockfish]

It was the original and has been in for a few years. I would think it is not time/years per say, but how many hours are on it and how often the motor cooling system was flushed and cleaned. In our case it was not flushed much at all during the fishing season as the boat stays in the Ocean most of the time. What I plan to do in the future during our annual maintenance is buy a t-stat housing gasket and pull it and clean the t-stat with a small softer brush and Salt Away and also pour a little strong solution of Salt Away right in the motor at the t-stat opening and use the salt away injection system from now on connected to the fresh water flushing hose. We started doing that this year. Apparently that stuff not only helps dissolve the crystallized salt but also coats parts and passages to reduce the salt sticking to them and plugging up the t-stat and small cooling passages. I think we would get a lot more life out of the t-stat doing that. You can also clean out a few salt crystals with your finger from the housing.

If you get the motor serviced at the dealer they will change the t-stat almost every time you take it in, especially if the motor is having some sort of problem, like making oil. Once with my old Yami 9.9 we replaced the t-stat and did some other work, rebuilt the fuel pump etc. but it was still making oil so we took it to the shop and among other work they replaced the new t-stat we had just put in with another new one. I asked for the one they took out to keep as a spare. Apparently you can put them in a pot on the stove and test them with a thermometer to see at what temperature they open but almost no one does that, they just replace them as a service item.

One issue I have with Yami is how much the dealers charge for the small t-stat. compared to say what is available for the auto industry. $60.00 and tax is a bit outrageous. I understand they have been using the same one for a couple of decades in the various Yami 9.9 kickers and also use it in some other motors, so there should be some demand for an after market one as that is a lot of motors that use the same t-stat world wide. It may be worth looking into if an after market one is available.