99 johnson 150 overheat

[wl6]

Hi all, Have 1999 Johnson 150 J150PLEES that was overheating... replaced stats,still overheat. I removed stats and ran on hose for 10-15 minutes and could keep my hand on both heads without burning. Also removed stat covers and started motor to see water flow and all is good.While running on hose,there is warm/hot exhaust water coming out in front of lower unit by shift shaft and the mid section cowling is very warm to the touch.
I did notice a big difference in tell tale water...with stats removed the pressure is next to nothing coming out(peeing).


Today I installed complete water pump kit, made sure water tube was lined up, still have overheat problem. When lower unit was off, I took hose to water tube and got good circulation up above thru powerhead.
What am I not seeing or have overlooked? Thanks

 

[wl6]

Re: 99 johnson 150 overheat....water deflectors??????

Re: 99 johnson 150 overheat....water deflectors??????

pulled both heads,removed a lot of RTV inside passages as obviously someone has had the heads off prior.

I bought red rtv and new o-rings for cylinders as this model does not have head gaskets. My question is does a J150PLEES 1999 150 have water deflectors? And if so, any pics as to where new ones need to be installed.

The exploded parts view of this model does not show deflectors,but was told that there should be deflectors installed.

Compression:
110 110
110 110
100 100

Will be getting the heads checked to make sure they are true and not warped.

 

[wl6]

Re: 99 johnson 150 overheat....water deflectors??????

Re: 99 johnson 150 overheat....water deflectors??????

Anyone know if J150PLEES has water deflectors?

 

[durban]

Re: 99 johnson 150 overheat....water deflectors??????

Re: 99 johnson 150 overheat....water deflectors??????

Anyone know if J150PLEES has water deflectors?

i solved the problem once & for good with PLAN B
http://forums.iboats.com/showthread.php?t=557547

 

[Faztbullet]

Re: 99 johnson 150 overheat....water deflectors??????

Re: 99 johnson 150 overheat....water deflectors??????

Anyone know if J150PLEES has water deflectors?

Yes they are hard plastic in holes of block and the RTV you found is factory and its normal to find several passages around block blocked as no water circulates thru them, it enters/exits head at top/bottom holes of head casting. Follow the manual on reinstalling heads as RTV location is important to prevent external water leaks. Do not remove/discard these or you will need PLAN C.....a rebuilt powerhead!!!

 

[wl6]

Re: 99 johnson 150 overheat....water deflectors??????

Re: 99 johnson 150 overheat....water deflectors??????

Thanks for the replies.
durban: your motor is a 84 and shows them in exploded view, mine does not.
faztbullet:yes, I will follow manuals instructions on rtv location for no leakage.

Have been told by OMC outboard mechanic of 30+ yrs that this motor does not have them! hmmm,I really need to look at block with flashlight tomorrow after work and see if any or remnants of deflectors remain.
After 91',the exploded parts view does not show deflectors for the newer years. Just would hate to put together and have a failure finding out it needed deflectors.

 

[Faztbullet]

Re: 99 johnson 150 overheat....water deflectors??????

Re: 99 johnson 150 overheat....water deflectors??????

You are correct about the deflectors, I had picture in my mind of a 90? motor:redface:

 

[wl6]

Re: 99 johnson 150 overheat....water deflectors??????

Re: 99 johnson 150 overheat....water deflectors??????

Got it all back together yesterday after pulling heads,cleaning all water passages and replacing o-rings, gave it a test today with running at 4000 rpm for 3/4 mile and temp gauge never higher than 160.And then of course lower than 160 when the stats open.have another issue,but wanted to give conclusion to this thread.

 

[hogan12009]

Re: 99 johnson 150 overheat

Was this overheat just bad head gaskets and silicone then?