ORIGINAL: Sean Bowf
Curious if the header gasket has anything to do with heat seperation between the header and the engine, and if folks use them.
I didn't use them when I first started all this, but the new header I got for the rigger came with one, and the MV has one, so I started using them.
Anyhow...what brought me to this question... I know it is starting to warm up (both air temp and water temp). But...I used to be able to pull my MV from the water and put my thumb right on the head with no problem keeping it there. With the last run I did, even with the HS needle 1/8th of a turn richer than I normally run, the head was too hot to touch. When I got home I back flushed the cooling system and the flow seemed good, and I did not see any junk come out of the head, so I am pretty sure I have decent cooling flow.
The main thing I changed was that I tore the header gasket when I took the motor out to replace the starter shaft (still have pull starter problems on the MV, even with a new pull starter). Other than that, I moved the rudder over and up just a hair to keep it from coming in contact with the prop (I would not think the 1/16th of an inch or so I moved it up would make that much of a difference...).
So not sure if it is just the change in outside temp, the loss of the header gasket, or the fact I moved the rudder...
Here is a link to my last run. I tried to watch the coolant exit the hull after the first tank, when I realized how hot it was...and it looks like it is coming out.
Sean
a comparison of the temps and weather conditions would probably help..
my mono (even though its gas) running when the water is in the 40's/50's and air 50's/60's would not get any heat in the motor. Run it hard for a few laps, bring it in and the head would be cool to the touch. Warmer water, warmer air temp, different humidity, different 'altitude' got motor got heat in it to where it was hot to touch after coming back, but also picked up RPM and speed.
Was the case warm and the cooling head was just cool or was the case cool also? Motor needs heat to make power, especially with a ringless piston. Ive blown header gaskets and it didnt make a difference in how the boat ran from what i could see.