1995 Yamaha 250 cooling issues

Badger2008

Petty Officer 3rd Class
Joined
Feb 4, 2008
Messages
76
1995 Yamaha 250
After about 5 mins at idle the heat alarms come on

New water pump complete with housing
New thermostats (It had none when I got it)
Cleaned out the Poppet valve.

The motor sometimes pees sometimes not. never very strong. Looks like a lot of water coming out of the lower unit. Can I just plug off the relief (Poppet) valve hose?

Anywhere else to look?
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: 1995 Yamaha 250 cooling issues

none of the 3.1L motors had pressure at idle like the 2.6L and V4.
however if its going away completly either something under the powerhead gave way from corrosion or the pressure control valve is leaking severely.
 

Badger2008

Petty Officer 3rd Class
Joined
Feb 4, 2008
Messages
76
Re: 1995 Yamaha 250 cooling issues

I have been running the motor with ear muffs. Have yet to test it on water. Perhaps the problem with not exist fully submerged? Is there a replacement alternative for the pressure valve?
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: 1995 Yamaha 250 cooling issues

its not the valve, even though there is a new one, its the grommet and the grommet pocket that bites you.
the grommet MUST be removed,the pocket carefully scraped and a NEW grommet installed.
 

Badger2008

Petty Officer 3rd Class
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Messages
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Re: 1995 Yamaha 250 cooling issues

Ok Rodbolt you have not failed me yet. I'll order a new gromet. I dont suppose there is an inline aftermarket valve?
 

Badger2008

Petty Officer 3rd Class
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Messages
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Re: 1995 Yamaha 250 cooling issues

OK today I removed the old poppet valve and gromet. I chucked a 10g shotgun brush in a drill and cleaned the hole out good. I'm ordering a new poppet valve kit if I can find one. I assume the new gromet fits over the recessed flange inside the hole????
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: 1995 Yamaha 250 cooling issues

yes, dont push it in to far.
if you do DO NOT remove the cover to retrieve it.
do a forum search or post it and I can tell you how to retrive it.
 

Badger2008

Petty Officer 3rd Class
Joined
Feb 4, 2008
Messages
76
Re: 1995 Yamaha 250 cooling issues

Thanks Rodbolt. Actually I dropped the original one inside trying to put it in. I had a brush with a loop on the end of the handle and cut one side out leaving a hook. It came right out :)
 
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