Promax 225 Poper Valve & Thermostat Question

[rarias]

Hi Merc Tech‘s,

I have twin 225 Promax on my Tunel and my mechanic recommended to replace with new thermostat w/seal, and poper valve System wich I find smart to do since Powerheads are new to me but used.
He mentioned that he has done in some racing preps a popper restrictor and deleted the thermostat and forget of any of them failing.

Would you do this mod. or stay with the systems as designed by Mercury?? I had in mind to stay stock.

Regards,
Raul

[Merc 2.5]

Well kinda depends on use of motors. But for normal use. stats and poppet , as long it's still on the 2 piece adapter plates

[rarias]

Pleasure and maybe 2 races a year.

regards,

[Greg G]

No need to change. Stay stock.

[tux974]

Stats, popet kit, and pulse pump rebuild would be my suggestion especially in salt if you are running a 2pc plate (stock cooling setup).
If you are running a 1pc adapter plate then you can run restrictors in place of stats but that should have been done already.
If you are not sure what you have post a picture of the back of the engine up close without cowling to best help you.

[tlwjkw]

looks like 2 piece maybe???

[rarias]

is

[rarias]

Appreciate your recommendations. Hope this picture helps.

[tux974]

Looks like you have a popet dump hose going to the top of the block so that tells me you have stock cooling with stock 2pc setup.
I suggest to leave it alone. Replace stats (143*) every year, at minimum check/clean popet but best to replace with complete kit especially in salt water.
If you do not know engine history or when last properly serviced rebuild pulse pump and clean VST. Having injectors serviced is also a very good idea but that will take a bit of work.....MPO.

[rarias]

Hi Tux974,

stayed all original and installed new popet kit and thermostat 143 with seal as recommended. There is a water tube that conectes to a plastic T divider and goes to the upper plate where the bushings are. What is the reason of this water??? (See pics)