Poppet Valve???

[Wayne Carrington]

I have a 98 mercury 200 HP EFI outboard on my 20ft. Nitro Savage. In previous posts from other people there were references to a Poppet valve controlling the water flow at high speeds. Does anyone know if my motor has one of these? and where it is located? My water pressure is bouncing between 10 and 15 psi at cruising speed. I had a new waterpump impeller installed. thanks in advance for any help I can get.

 

[Jim clear]

I believe you do have one. Looking at the motor from the rear, it is on the right side of the block down low. You have to remove the lower cowel cover to get at it. Not a real hard job to replace. Just have to be careful getting out the old seal and making sure the new one is seated evenly. You can buy the whole kit that comes with gaskets etc. and you will have to put together a couple of parts and a spring. I am sure Bob will answer this request. He wont steer you wrong.

 

[Bob Bourget2]

Yes, it does have one. It's sole purpose is to control water flow OUT of the block, at ALL, rpm's. The "bounce" you are experiencing is the poppet valve "popping" open / close at that rpm. It should be replaced if not done yet.

 

[Wayne Carrington]

Thanks for the info. I will look into ordering a new one this week.