Non-supercharged jet pump on a supercharged ski

[Rv17]

First of all thanks for accepting me here… so I restored a 2003 GTX 4 tec SC, rebuilt the motor and replaced the jet pump for a metal one which I ordered from Ebay listed as: 04 GTX 4 tec limited SC. I Put the ski in the water and runs fine at low speeds (35-42 mph) when i go over that after about 5 minutes the Hi-temp alarm comes up, i replaced both temp sensors checked for clogged lines and everything seems to be fine but I noticed a difference on the jet pumps, the water inlet looks bigger on the old plastic pump. Do you guys think that’s why when i go WOT the hi temp alarm comes on? Maybe not good water pressure at higher RPMs?

 

[skiasylum]

Makes sense that the smaller inlet would restrict water flow for exhaust system cooling, and the exhaust temp certainly rises at higher RPMS.

 

[ski-d00]

The opening size is not your problem. I've done that exact swap at least a dozen times, most back in the mid 2000s and never had any issue with cooling. A lot of high exhaust temp problems at WOT are from clogged j-pipes or exhaust manifolds.

What color reducer are you using between the pump and hull?

 

[Rv17]

The opening size is not your problem. I've done that exact swap at least a dozen times, most back in the mid 2000s and never had any issue with cooling. A lot of high exhaust temp problems at WOT are from clogged j-pipes or exhaust manifolds.

What color reducer are you using between the pump and hull?

The red 7mm id, i just ordered the yellow one 8mm and see if that helps

 

[ski-d00]

I doubt it will help. I suspect a blockage or corrosion. Did you clean the 3 holes on the j-pipe?

 

[Rv17]

I doubt it will help. I suspect a blockage or corrosion. Did you clean the 3 holes on the j-pipe?

Will do that too.. the other detail I should mention is the impeller is also from a non SC Gtx