250 yamaha Cooling system issues

[Badger2008]

1995 250 Yamaha 2 stroke

Motor ran with weak pee stream after 5 mins alarm comes on.

Replaced entire waterpump with housing. Checked both Orings in place.

Replaced entire poppet valve assembly.

Replaced both Thermostats.

Motor wont pee from the taddle tale. After 5 mins motor alarms. (Running on muffs)

When I put the muffs on water comes from 3 holes in the lower unit 2 on starboard and 1 on port.

What else can this be? Is it that these motors dont get enough water from earmuffs?
Is there anything else to check on the waterpump installation?

Anywhere else I can tap water for a taddle tale? Maybe the bolt on top of the starboard head replaced with a fitting?

Pull the Heads?

 

[jeffersondodson561]

Re: 250 yamaha Cooling system issues

did you put the grommet into new water pump housing, oring on the water pump housing, off it's track?

 

[blackgun6109]

Re: 250 yamaha Cooling system issues

pull the heads and clean them out, yamaha's grow some nasty stuff in the water jackets.

 

[rodbolt]

Re: 250 yamaha Cooling system issues

that engine overhating on flush muffs is not uncommon.
you need about 45 PSI and a 3/4" hose minimum or it gets hot.
also ANY sign of melt in the pump housing means the housing is scrap.
any corrosion buildup under the damper seal holder will create low speed overheats after pump replacement.

 

[Badger2008]

Re: 250 yamaha Cooling system issues

Does the low pressure hose connection also cause it to pee poorly or not at all?

Also forgive the ignorance. What is a damper seal holder?