'03 GTX SC & PUMP FLEXING...

[aquagrip]

Who has had problems with cavitation, due to the pump flexing? Mine has 20 hours on it and I pulled the pump and was amazed at the amount of wear ring damage. Not only scraped off plastic, but melted plastic, I have never seen anything like it.

What is SeaDoo doing to address this problem? I can't locate a wear ring, so I machined one out of a solid block of aluminum and am putting it back together today. I am hoping that this will strengthen the pump and work well as a wear ring.

Bill, what have you experienced?

-Todd (AquaGrip)

[mtd4tecsc]

From an earlier post...

For all of you SC owners that have been losing speed both off the line and on top speed....

Skat-Trak has just released a new, inexpensive fix for the problem! They will take your worthless composite SC pump and modify it to accept a twin bearing system instead of the oem single bearing. They also take your wear ring out, trim it down, and cover the inside with a machined, stainless steel wear ring.

There were two problems with the composite pump. First, the single bearing could not handle the power of the SC motor. Aggressive riders could wear out the single bearing in just one afternoon! The single bearing had no support and would start allowing the impeller to cut deep into the wear ring. On my race boat, I was losing 3-5 mph by the end of a hard ride. The twin bearing system gives the new Skat-Trak impeller shaft tremendous stability. No more problems with worn out bearing or torn up wear ring, and no more cost to repair and replace them.

The second problem was that the pump housing would flex under severe acceleration and when the ski comes out of the water, changing the load quickly. Well, the stainless steel insert is just enough to stiffen-up the housing enough to prevent the vast majority of pump flex.

With these two problems resolved, you will be able to keep the acceleration and speed you paid for when you bought the SC. I have not been told the fix price, but I can tell you that it costs from $200 - $400 to fix your pump with oem parts. Add the fact that your ski will be down for a few weeks each time, you can see that Skat is the only way to go when your pump starts to go out.

How do I know it works? That's easy, because I got tired of fixing the oem pump on my race ski and have been working with Skat-Trak to help them come up with a fix. They did it ! And you don't even have to buy a new pump housing!

[Hagar]

Can you advise what clearance you used between the SS wear ring sleeve and the impeller?

What is the machined length of the wear ring for a S/C 4-Tec?

Thanks

[mtd4tecsc]

Clearance is as tight as you can get it without rubbing. No greater than 1/32 from entire edge and you have pretty much got it nailed.

The machined length is identical to the stock ring.

[seadoo]

I have two 2002 4 tec's ( not SC ) both of them with the jet unit problem, bearings, shaft, wear ring and seals.

Is this is a factory problem????

As i heard on this forum the SC will broke the jet unit in a couple of hours and the 4 tec's some hours after because of less power.

[Colin]

We recently machined up 2 Stainless wear rings for our two 03 4-tec S/C's. Took out about half the composite ring and machined the SS ring as true to the bore as possible.

The standard composite pumps were retained despite them being out of round and not very true. The standard impellers were retained.

The new SS rings were intended to improve 3 things.
1: Stiffen the plastic pump body & prevent twisting under load.
2: To "true" the impeller to the bore of the wear ring
3: To reduce the tolerance between wear ring & impeller.

We took one to about 15 thou clearance the other to 5 though clearance.

The results are amazing. Virually no cavitation"feel" out of the hole and incredible increase in acceleration. Excellent improvement in the feel of the drive, little or no vibration.

[dnoel]

A stainless steel wear ring won't solve your problems. If you look closely at what they are called... wear ring... They are made to wear out, hopefully before other more expensive harder to replace parts.

If you replace the soft plastic with hard stainless steel when you suck something into the pump (or have problems due to the bearings), your going to trash your impeller, and probably new stainless wear ring.

The mangled wear rings aren't the cause of the problem, they are just a symptom. Easily mangled (and easily/cheaply replaced) wear rings are designed that way for a reason.

[Bill O'Neal]

We get $395.00 to completely rebuild the 4 TEC pumps, including the extra bearings, shaft, stainless steel wear ring, collar, everthing needed to fix the problem.

[Colin]

Whether they are called "wear" rings or not (some are called liners) more than one manufacturer uses Stainless ones as Original equipment.

As regards, cost. They cost me less than an OEM plastic wear ring.

The point about addressing a solution rather than a symtom, is not correct. The SS ring is supposed to stiffen the pump to stop or reduce the problem.

Now, with 15 hours since fitting both with ss rings, both 4-tecs appear to be travelling well with little or no cavitation. We wore out plastic ones in less than 15 hours.

However, next time as a means of saving "down" time, we are going to experiment with making the the outer ring of SS and fitting a standard plastic liner that's had its O.D. machined down to suit th ss sleeve. If this works as well, the fitting of a new liner will take the same time as a standard plastic one does. now.

It just may be the best of both worlds.