Polaris SLX1200 Rescue

[0l0dom0l0]

Cleaned up pretty good.

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Engine work began. This one really put up a fight. Many snapped bolts and pain was to come. Quickly concluded that the engine had never been apart.

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Cause of the low compressions on the white ski discovered. The mag piston had got a bit hot I think, not much else. Bore was still good.

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Crank not too bad - some light rust on the bearings but it mostly rubs off. All the bearings felt okay when it came out and both ends of the crank look good so I've decided to clean it up and re run it.

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Ended up with a host of parts for restoration:

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Needed about 7 broken bolts removing from the white jet ski jugs so took them to my friend who worked his magic. He also tidied up the mating surfaces for me. Heads were shot blasted so they can be repainted too.

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Then they got professionally re-honed.

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So back onto the black jet ski engine now. I wanted to take the white jet ski engine apart first to see what was salvageable and work out the most economical way to fix them both. Conclusion was:

Black engine - rebuild with brand new rebuilt crank and 0.25 O/S pistons I'd already purchased.
White jet ski - run the original crank with standard bore, using the best clean piston from the black engine to replace the damaged one.

Work then commenced on repainting the parts that I needed:

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Accelerator pump lined added and the carbs "bench synced" after bolting them to the inlet manifold and loosening the screws that hold them together to "clock" them into place.

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Time to move onto the bottom end. I've been trying to get hold of a bore gauge to check the cylinder clearance as I wanted to assemble the engine in one go. In the end I got impatient and started working on the bottom end anyway. The top of the cases was surfaced as the previous rebuilder looked to have used about 15 grit sand paper to clean them so I will need to check the squish when the barrels are installed.

Here's my rebuilt crank. The end play on one of the rods is more than I'd like really. I've measured it at 0.58mm which is out of spec, and 0.02mm above the service limit but the shop is 2 hours away. I don't think it will be an issue.

[0l0dom0l0]

And that is where I am up to for now. I had to trim the tabs off the face of the seal to get the inner seal in but otherwise the cases went together okay. Used the factor recommended three bond sealer.
I'm now waiting on a tool to get the circlips in the new pistons. I can't get them to go in and have already deformed one. Luckily I have a spare.
I have also measured the piston to wall clearance very crudely with a feeler gauge on the newly bored cylinders (as it is the only thing I have). To do it I simply put the piston in the bore and looked to see what feeler gauge I could get between the piston and the wall. 0.16mm is a little on the tight side, so about 0.006" or so - which is probably a little tighter than I'd like it to be and the manual calls for (0.0065" min). I'm going to try and get hold of a bore gauge to measure them once more. I think they will be okay to run but I'll need to make sure the engine is warmed up for 10 minutes or so before hammering on it and that it gets a good few hours of running in before I go crazy.

[xlint89]

Looks good. Nice documentation too.