1996 Yamaha 130 Overheat *WITS END*

[speckledtrout]

Hey guys, I'm throwing in a gift certificate to your favoriate resteurant for anyone who can point me in the right direction. My twin 1996 yamaha 130's (TLRU) run great at any RPM under 4000. Will run all day long. It started with the Port engine. Anything 4100 or above, will keep running for about 40 secs. to 2 min., then low rpm shut down with warning buzzer on and temp light blinking on the yamaha gage. Poppet/pressure relief was first thought, so, out of abundance of caution and given little expense for parts, changed out both assemblies including 1)valve 2) spring 3) gromet and 4) gasket. Looks like valves were retrofits. Problem not solved?? Also, the Starboard engine is now acting up also. When the Port engine goes down, its rev limits both engines. The same thing happens if I keep the Port engine below 4000 and run the Starboard up over 4000. I didn't replace valve "caps", although I do have new ones (the caps with the water hose intake nodule on it). The dealer I origianlly brought to for service said the poppet valve was only "stuck" and that he "cleaned it out". But same problem after I replaced both myself???? Both lower units just resealed and brand new water pump assemblies in each. Any advice is greatly appreciate!! Thanks.

[HEDJUG]

Since its both engines, you may have run thru some weeds or muck & the system is clogged up a bit. Try flushing the heck out of them & check the intake screens. Or, the new pumps were put in wrong somehow & can't keep up.

If that helps, for the resturant, Striped Bass in Philly will do fine.

[speckledtrout]

Did all of the above. Re-checked impellers in both pumps. Water flow through system seems fine. Thanks for the effort, though.

[Billable Hours]

Have the impellers ever been replaced? Maybe the impeller / pump housing is worn? Would probably pump fine at idle, and then decrease in pumping as the rpms go up.

Delmonico's in Vegas, please . . .

[T-Craft]

pull the thermo sensor out and check them, then check the thermo-stats, if that doesnt do it your pasages in the heads could be cloged up with corrosion or garbage, could also be the water jackets (head covers).

[danielb]

Might have to bite the bullet and have the computer trouble codes read to see where the problem is exactly, rev limiting on yammis could come from the computer over heat, bad coils, power pack and any one of a couple of sensors.
What is it that both engines are getting that is causing the problem? (Fuel and electricity)
Could be the gas supply, have you checked the filters on the engines, they have an orange donut in them and when water is present the donut floats in the clear plastic filter holder to indicate the presence of water.
How is your charging circuits, low battery voltage will cause this too.

Good luck