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After a suggestion from Dave in DE, I began to look for a cylinder exchange for a 2003 XLT 1200.

SBT has one for >$700, which uses a carbon steel liner.
After contacting WSM, I was told that they do not carry a cylinder exchange for the PV 1200, due to the Nikasil plating, They would be more than happy to sell me 3 new cylinders with pistons and PV for roughly $630 a set.


Being the Waverunner is 16 years old, I will likely go the SBT route, but it got me to thinking what the real benefit of the Nikasil coating is in a pwc application.


I understand that the wear rate on a coated cylinder is better, but in the case of a 2 stroke engine is wear the culprit for most engine rebuilds?
In my years of toying with 2 stroke outboard motors, most engines were casualties of oil starvation or poor fuel long before they were worn out.

From what little I have had time to research, it seems as though an engine like the PV 1200 has a realistic life expectancy of 300 hours. If this is true what could one expect to get out of a carbon steel sleeved engine?

It doesn't seems as though these engines turn a very high rpm , so is heat transfer a true concern when going with a steel sleeve?

I'd love to hear input on why one had chosen to go one way or the other.

Either way this is most likely just rambling at the moment as I still need to pull my engine to be sure of the integrity of the bottom end.
 

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After a suggestion from Dave in DE, I began to look for a cylinder exchange for a 2003 XLT 1200.

SBT has one for >$700, which uses a carbon steel liner.
After contacting WSM, I was told that they do not carry a cylinder exchange for the PV 1200, due to the Nikasil plating, They would be more than happy to sell me 3 new cylinders with pistons and PV for roughly $630 a set.


Being the Waverunner is 16 years old, I will likely go the SBT route, but it got me to thinking what the real benefit of the Nikasil coating is in a pwc application.


I understand that the wear rate on a coated cylinder is better, but in the case of a 2 stroke engine is wear the culprit for most engine rebuilds?
In my years of toying with 2 stroke outboard motors, most engines were casualties of oil starvation or poor fuel long before they were worn out.

From what little I have had time to research, it seems as though an engine like the PV 1200 has a realistic life expectancy of 300 hours. If this is true what could one expect to get out of a carbon steel sleeved engine?

It doesn't seems as though these engines turn a very high rpm , so is heat transfer a true concern when going with a steel sleeve?

I'd love to hear input on why one had chosen to go one way or the other.

Either way this is most likely just rambling at the moment as I still need to pull my engine to be sure of the integrity of the bottom end.
Chris,
Sorry didn't know wsm quit selling exchange kits.

Heat transfer is the main reason behind the nikasil coating. With the nikasil coating over an alluminum bore heat transfer is quicker than through a steel liner.
The steel liner lasts about the same time frame maybe a tick shorter. However you can rebore the sleeve several times in .25mm increments.

USChrome will replate scored cyl's but again it's pricey. Around $350/400 a cyl. But it's very high quality work and far thicker and better than OEM.

Most pwc 2strokes turn around 7500/8000 RPM that's why there life is much shorter than an OB motor. Most OB motors run a little over half that speed if that.

Send some pics of bad cyl/cyl's
 

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Discussion Starter #5
Pics sent. Thanks Dave
I should have some time to get the engine out in the next few weeks. Depending on how cylinder 1 looks, I may go the US Chrome or Millenium replating route.

In most rebuilds, I am finding it hard to see the cost effectiveness in the replating.

Which begs the question as to why there only seems to be one company who sells an exchange for cylinders with a carbon steel sleeve. Specifically when you consider the low engine life expectancy and the ability to rehone the sleeve.
 

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Heat transfer is one of the main reasons for plating. The more heat you can get away from the exhaust port side of the cyl wall and piston, the better off, plus there's no having to line the ports up. If they're off it's not just a matter of, well it's off a little, so just grind it open to the right location. The ports must maintain the designed size and location or big power losses or power band changes can result. Weight would be another issue in my book. Cyl's with cast iron sleeves weigh substantially more. There's a ton of pro's and cons for each, and all could be justifiably argued, but if a engine was designed to run a plated cyl, I would stick with it.
 

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Discussion Starter #7
Heat transfer is one of the main reasons for plating. The more heat you can get away from the exhaust port side of the cyl wall and piston, the better off, plus there's no having to line the ports up. If they're off it's not just a matter of, well it's off a little, so just grind it open to the right location. The ports must maintain the designed size and location or big power losses or power band changes can result. Weight would be another issue in my book. Cyl's with cast iron sleeves weigh substantially more. There's a ton of pro's and cons for each, and all could be justifiably argued, but if a engine was designed to run a plated cyl, I would stick with it.

Thank you for the input.
 

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Based on what I see in the pics it looks like there's water in this motor witch means certain death for the crank also.

The cyl appear to be sleeved already. But I can't be certain till I see the lower end of the cyl. Will be interesting to see if this is an sbt motor when you get the cyl off.
 

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Discussion Starter #10
Ok, so that would explain the rust on the cylinder.
I should have the engine out next weekend.
 

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Man, I would be scared to fire that engine for fear of the crank bearings coming apart. Been there, done that. Not pretty.
 

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Man, I would be scared to fire that engine for fear of the crank bearings coming apart. Been there, done that. Not pretty.

I am going to get the engine out and pull the cylinders, but at the moment I am becoming resolved with going the rebuilt engine route.


I cant see how purchasing a new crank, and cylinder exchange makes sense for minimal savings.
 

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Man, I would be scared to fire that engine for fear of the crank bearings coming apart. Been there, done that. Not pretty.

I am going to get the engine out and pull the cylinders, but at the moment I am becoming resolved with going the rebuilt engine route.


I cant see how purchasing a new crank, and cylinder exchange makes sense for minimal savings.
Ya, from what I'm seeing, Id say a rebuilt motor would be to your advantage. Im sure your going to find the crank is shot also. By the time you figure crank and cyl's along with everything else you'd be ahead of the game with a new motor.
 
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