Overheating Yamaha

Anyone having problems overheating with 90 degree water

90 degree water is probably not your problem....how long since you changed out water pump?

Impeller, thermostats, and/or poppet valve. Likely one or a combination. Only other cause would be an obstruction in water flow somewhere.

^^^^^ this

Never had a problem with something like that. Hope you get it figured out.

Had same problem, it was a water pump problem, 200 bucks

if it only does it when you are idling around you have sand and small rocks in the poppet valve and need to clean it if it does it running on plane water pump or t-stats

2 bills??

Takes 30-45 min and the kit is 75 bucks

You might ask in the Equipment Discussion forum.

More like an hour of labor. 120$ plus parts. He was correct at couple a bills.

Make sure the plastic screens on the Loweunit are not broke. This will cause em to overheat running.

Who doesn't replace the water pump themselves?!

Replace the water pump. Super easy. Takes 30 min on a merc, not sure on yamaha

On a 90 or 115 easy to replace yourself. On a 250 much more difficult if you don't have help. Sounds like water pump to me. Do you have a water pressure guage?

Pulling the prop helps on the bigger motors. I do a 200 solo, and it's not too bad.

What year and model engine? OX66? HPDI? Vmax? Had something similar happen to me after idling through a silted area, sucked a bunch of that into the water jacket and restricted the water flow.

if it only does it when you are idling around you likely have a clogged screen, dirty and/or old style poppet valve. An upgrade is available. Could still be a water pump or thermostat, but you need to check your water pressure and look at the tell-tale stream as you go from idle to full throttle. I have had each, the symptoms are all a little different.

I have a 200 hdpi doing the same thing it has a new water pump. What water pressure should it have on plane?

Just recently did impeller kit, both thermostats and poppet valve on mine. Overheat light only came on once idling out of cove but went ahead and did everything at once.

With upgraded Poppet valve, I'm over 20 on plane.

Got a new water pump and impeller in April and last week I noticed my HPDI running about 7-8# WOT. I never got an overheat light and nothing noticeable every seemed wrong on a 4 day lake trip, but I went ahead and dropped it off at the shop on the way home. I am really pissed if they find a problem because it takes 3-4 weeks to get your boat back this time of year. Cant stand leaving my boat at a shop that long.

My Yamaha 200 was doing that and it was the PRV (pressure regulating valve) stuck closed. This valve will open and close regulating the water pressure to the block. Mine was overheating when I was idling around. It was stuck in the closed position which was not allowing water to cool the engine at low RPM. You still need to change the water pump and impeller and if it keeps doing it then replace this. Its located on the top of the motor and easy to change.

Just got a call from shop , cowl was full of dirt dobbers , surprised you did not lose motor , they had R/R lower unit ( insurance ) about 2 weeks prior motor running hot , any one had this happen to them before with dirt dobbers in cowl ?? Motor never ran hot before . But I leave boat in slip . Never thought about cleaning or even checking cowl for obstruction .

Was at Pines, and a guy next to me at the ramp had the same problem. He caught it and had to do the clean out himself (at the ramp).

Those dirt dobbers are great critters, but tough on boats! they also like to fill up your wee-wee hole with mud. You can stick a q-tip in there when you're parked and they'll stay out. I don't know how your cowl is made but maybe you can do something similar.

It's a ox66 ,Yr: 2000 , 200 hp Yammie .

Put a Tough Skinz cover on it. It has mesh that covers the air intake which would keep them out of the cowl.

I would be more worried about the dirt nest breaking apart and sucking into the intake and destroying the motor. I check mine out on a monthly basis. I have my boat in the garage and the little devils still figure out how to get nest built in it.