2002 GTX DI Throttle Sweet Spot

[Wess]

Yes large hull, I need to replace my wear ring, maybe get a couple more mph. Probably wouldn’t hurt to rework my impeller to for a little more.

 

[mikidymac]

Is that the Large Hull GTX?? I have a 2003 951 DI. I was wondering about the top speed.

Here you go..... These are actual Radar numbers by Group K, not GPS or the factory Dream-O-Meter.

MODEL​	LENGTH​	WEIGHT​	STOCK HP​	STOCK PEAK SPEED​	Group K “Sleeper Kit” TOP SPEED​
‘98-‘01 GTX 951 Carburetors​	124​	664 lb dry​	130​	57-58 mph​	62-63 mph Info for Sleeper Kits​
’00-‘01 GTX 951 Di​	124​	681 lb dry​	130​	56-57 mph​	​
’02-’03 GTX 951 Di​	130.4​	715 lb dry​	130​	51-52 mph​	56-57 mph​

 

[etemplet]

I was hoping for about 57 it being a 951 and all that. At least when I get it running I won't think something is wrong and try to find speed/performance where there is none to be gained. Good info bro. I always appreciate it.

 

[Wess]

I knew the new hull design slowed them down in 2002, I was riding with others with the older design and they were faster.

 

[HateMyGTXDI]

I wanted to post an update on what I have found so far. The exhaust manifold had a missing section of the internal ring. I managed to remove the exhaust manifold, but only by cutting it around two to the 3 stuck bolts. Then I found that the Air Temp Sensor that is supposed to be inserted in the intake was laying in the bottom of the hull. So I'm sure it was sending false data to the MPEM. So I decided to go further and check the reed valves, and sure enough, one of the reeds was broken.

I finally have all the parts and want to start reassembling them. I have a question about Molykote 111 and Loctite 243 and Sealant, Loctite 30542:

For the exhaust manifold bolts, the manual says to use Molykote 111 on the threads and Loctite on the head of the bolt. I couldn't find Molykote 111, so is it ok to use Permatex Anti-seize Lubricant 80078 (which I have on-hand) instead? And to confirm, the Loctite is applied to the bottom of the bolt head? Correct?

Then, on the exhaust pipe where the copper ring "gasket" is installed between the exhaust head pipe and exhaust cone, the manual says to apply Sealant, Loctite 30542. But would Permatex Optimum Max Temp (#27038) work? It's what I have on-hand too.

If none of these work, I will wait and purchase the Molykote and Loctite.

I still need to get the fuel pump out to see if it is indeed an aftermarket or the OEM. Once I get the above issues fixed, I will get on that fuel pump.

Thanks again for all the help!

 

[HateMyGTXDI]

Also, I have looked thru the Seadoo manual but can't find the torque setting/sequence for the intake that holds the reed valves. Can someone point me to the part of the manual OR let me know what the torque on those bolts is supposed to be?
Thank you!

 

[mikidymac]

Antiseize or grease is fine on the threads. Blue loctite on the head.

For the exhaust copper ring use Permatex Ultra Copper RTV available at any auto parts store.

If the torque isn’t listed in the manual just look up the bolt size on a generic torque chart for that size.

 

[HateMyGTXDI]

Thank you mikidymac!

 

[HateMyGTXDI]

OK, I finally got the replacement reed valve and installed them both, installed the intake manifolds/reed valve covers (called Carburetor Adapter Ass'y on the below exploded view), applied Loctite to the threads and torqued the bolts (#23 below) to 10 nm. Hopefully that works. I found that spec on a generic torque chart.

Then I installed the exhaust manifold and initially torqued them to 17 ftlbs and again at 30 ftlbs, in the recommended sequence. I used antiseize on the bolts and threads and 243 Loctite on the heads.

I applied the antiseize to the bolts prior to inserting them into the manifold. The reason I did this was because four of the original bolts were so corroded that they were seized in the old manifold bolt holes. I had to cut the old manifold off in order to remove it. It wasn't coming off any other way. My hope was the antiseize would coat the bolt holes so I could avoid this problem for future repairs, if necessary.

My question is, I got some of the antiseize on the manifold where the washers and bolt heads meet. Do you think the antiseize is going to reduce the effectiveness of the Loctite? I will have to remove the bolts, clean the manifold and start the sequence over if that is the case.

 

[jhjesse]

you should be good. I have done the same thing with no ill result.

 

[HateMyGTXDI]

Thanks jhjesse! Appreciate the response.

Now that I have everything back together, I want to test for water leaks. I think I read on one post in this forum that it isn't a good idea to run water thru the jet ski without the engine running. The reason was that water can get into the cylinders and flood the engine. But then I watched a video where a guy ran water thru the ski for 10 minutes checking for leaks WITHOUT the engine running. What is the consensus here about this? Is it ok to run the water without running the engine?

 

[HateMyGTXDI]

Thanks jhjesse! Appreciate the response.

Now that I have everything back together, I want to test for water leaks. I think I read on one post in this forum that it isn't a good idea to run water thru the jet ski without the engine running. The reason was that water can get into the cylinders and flood the engine. But then I watched a video where a guy ran water thru the ski for 10 minutes checking for leaks WITHOUT the engine running. What is the consensus here about this? Is it ok to run the water without running the engine?

 

[jhjesse]

Engine on water on. Water off engine off. DONT DEVIATE from this or you will fill the cylinders with water.