Engine overheat problem

[pioui1]

I Have 760 engine, a 61X cylinder oversize at 84.00 and port ,the engine had a great performance, but suddenly I put my hand where the water pisser are located and the water is warmer than usual ,I put my hand the B-pipe chamber and its very warm

I open the both screws on the carburetors by a full circle , it did not changed much,
I open the carburetors and every thing is clean but I replace the 2 diaphragms and I replace the fuel filter,
I put the timing to zero and the temp of the engine went down a little bit,
I notice the fuel check valve needs to be replace,
all the water hose are in good shape, dual cooling

But my hull cooling tube are half a inch instead of 3/8 and when I put my mechanic in the Trinity hull, the over heating problem started

 

[DylanS]

I have a similar set up that did this to me. Tore the ski apart trying to figure it out, ended up just adjusting the b-pipe and was golden lol

 

[TheBuzzard]

if the tube in the hull is cracked between the pump and bulkhead, that will cause insufficient cooling water pressure. I've seen that once.

 

[Tyler Zane]

I don't know that I would be too concerned. You can't put your hand on my b pipe chamber after a good run and my pisser's will nearly burn you. Whats your temp on the head? Get yourself a temp gun. I run about 140-150 on the head, I have a temp strip on it to monitor it.

If you do have a cooling problem, you don't need to be adjusting the carbs.

 

[E350]

Hey guys, I noticed that the JF650 in our 1988 X2 was running hotter than usual on the last two trips so we stopped skiing it. I noticed that not only was there more exhaust gas coming out of the bow exhaust pipe but that even the bilge water was warm/hot. So, I tested for vacuum sealing and then for pressure sealing by blocking off the intake to carburetor and the exhaust manifold to pipe and, well, there is no vacuum or pressure sealing whatsoever. So I am waiting for oem Kawasaki crankshaft seals from Blowsion to install. I figured that the extra heat was from the rear piston running lean. What do you think?

 

[cookn]

I am having a cooling issue right now that sounds similar and I suspect that when I pull the exhaust manifold that its going to be packed full of sand and crushed up shells from beaching my ski all the time and firing it up too close to shore

 

[Tyler Zane]

Hey guys, I noticed that the JF650 in our 1988 X2 was running hotter than usual on the last two trips so we stopped skiing it. I noticed that not only was there more exhaust gas coming out of the bow exhaust pipe but that even the bilge water was warm/hot. So, I tested for vacuum sealing and then for pressure sealing by blocking off the intake to carburetor and the exhaust manifold to pipe and, well, there is no vacuum or pressure sealing whatsoever. So I am waiting for oem Kawasaki crankshaft seals from Blowsion to install. I figured that the extra heat was from the rear piston running lean. What do you think?

You probably didn't do the leakdown test correctly. Where did you hook up the pressure tester?

Even a "warm" running engine, I'm not sure why you would jump to a leakdown test...

 

[E350]

Thanks Tyler, I will show my homework next week with pictures, and you may be right that I am not doing the leakdown test right.

 

[Pro-pulsion]

I have a similar set up that did this to me. Tore the ski apart trying to figure it out, ended up just adjusting the b-pipe and was golden lol

^^ This ^^
My B-pipe was running too hot as well, if I touched it I would almost stick to it. Cooling lines would bounce against it and stick to it, the heat transferred back to the rest of the pipe and caused warmer than usual temps. I opened the top screw up about 1/8 of a turn more and it cooled everything down properly with no noticeable change in performance.

 

[Proformance1]

Had an issue similar years ago, found a zebra muscle in one of the b pipe elbows turned sideways. Turn up the water to the pipe as stated and see how that works

 

[DylanS]

^^ This ^^
My B-pipe was running too hot as well, if I touched it I would almost stick to it. Cooling lines would bounce against it and stick to it, the heat transferred back to the rest of the pipe and caused warmer than usual temps. I opened the top screw up about 1/8 of a turn more and it cooled everything down properly with no noticeable change in performance.

Exactly the same lmao