Tohatsu 140 compression

[81golfcaddy]

Checking the compression today on the engine and all cylinders check 125 psi. Is this within specs

 

[ahicks]

The fact they are even tells most of the story, that you're good to go. As an example, if one were half of what the others are, then you know you have an issue.

Bonus on yours is that they are at 125psi. That's pretty good.

 

[81golfcaddy]

Thanks it had me worried today it ran a little hot when at full throttle found out my water pressure was a little low got new pump on the way

 

[ahicks]

That's the incentive (fear of overheating to the point of causing major damage) to replace an impeller of unknown age when you pick up a used engine (and regularly afterward). Replacing that with a high quality OEM impeller the first step if you have any plans on keeping it for a while....

 

[pvanv]

That's the incentive (fear of overheating to the point of causing major damage) to replace an impeller of unknown age when you pick up a used engine (and regularly afterward). Replacing that with a high quality OEM impeller the first step if you have any plans on keeping it for a while....

Yes. I would take it one step further, and do the complete wp kit (when available), if there is any sign of wear to the cup or plate; same labor, minimal additional parts cost.

 

[81golfcaddy]

10 04 will do thanks for the heads up

 

[81golfcaddy]

Curious what should the water pressure be at Full Throttle

 

[ahicks]

Difference of opinion, replace the impeller vs.installing an entire kit, is the difference between a dealer's logic and somebody working under less stringent conditions - as in hobby or working on your own "stuff".

Paul needs to max out his time/efficiency. Get in, get out, and move on to the next job. He wants whatever he needs there waiting prior to even starting the job. Those working on their own stuff, or working as a hobby, can disassemble, see what needs to be done, order the parts, wait for them to arrive, then assemble. End result is not much different, but often the cost of the parts is lower doing your own work (not to mention labor), as those parts replaced are only those that need it. E,G. 25 dollar impeller vs. a 75 dollar "kit". In Paul's defense, you do need to have the skill to make a call on worn parts. Replacing just an impeller when you have scored housings or other parts is just a false economy. That pump is not going to last near as long as if you had installed the kit. -Al

 

[ahicks]

Curious what should the water pressure be at Full Throttle

Like you would be peeing after drinking a gallon of water.

 

[Sea Rider]

Changing a complete water pump kit is no indication that will restore an OB full peeing pressure, it's relative as to where the OB is being used, if salt water used the whole powerhead will have excessive salt layer formation and crust throughout all water paths lessening the peeing pressure due to less volume of water passing through if compared as to the full peeing pressure achieved when out of the box.

A new water pump kit will definitely perform much better than a highly used one..

Happy Boating

 

[81golfcaddy]

Just wondering psi wise since it does have a gauge and alarm.

 

[ahicks]

No clue what might be "normal". If it's seems to be running OK, just monitor it for a drop to unusual levels.

 

[pvanv]

Typically 5 or 6 or so PSI. Always under 10.

 

[pvanv]

Difference of opinion, replace the impeller vs.installing an entire kit, is the difference between a dealer's logic and somebody working under less stringent conditions - as in hobby or working on your own "stuff".

Paul needs to max out his time/efficiency. Get in, get out, and move on to the next job. He wants whatever he needs there waiting prior to even starting the job. Those working on their own stuff, or working as a hobby, can disassemble, see what needs to be done, order the parts, wait for them to arrive, then assemble. End result is not much different, but often the cost of the parts is lower doing your own work (not to mention labor), as those parts replaced are only those that need it. E,G. 25 dollar impeller vs. a 75 dollar "kit". In Paul's defense, you do need to have the skill to make a call on worn parts. Replacing just an impeller when you have scored housings or other parts is just a false economy. That pump is not going to last near as long as if you had installed the kit. -Al

Al is 100% correct. If you do your own labor, no cost there, and some kits are double the cost of an impeller. The kit for the 140 has an MSRP of $105, whereas the bare impeller is $53.35. Plus, as Luis can attest, often, if you have the time, you can polish the plate and cup. However, if charging a customer $100 an hour for labor, and if the cup and plate have wear, better to do the kit.