Some people eh.

[Mekanix]

Found a project 97 xp, runs, cheap, "po just did the top end" but hey its cheap.....

Well good thing I checked before trusting anything.

Piston's WSM platinum standard size.
Bores 0.5 over and scored, as in po though they were never bored in the first place.
Needed to go to 0.75 or 1mm over and new pistons to fix this lol. What a waste of new pistons.

Funny thing is that this is the second 97 xp that I've had to do this with.
Am I missing something? Is there such a thing where we have to now have 0.5mm or 0.020" clearance on these 787's lol

 

[IDoSeaDoo]

LOL you're kidding!! They must've been slapping around in there like mad! Did it trash the pistons? I'd look into anything else they "rebuilt". Did it actually run with those pistons? What was compression?

I bought a GTI once that was taken to a shop to have an SBT motor installed. The "mechanics" didn't remove the pump, rather slid the motor fwd, and estroyed 3 of the 4 motor mounts, installed the fuel strainer upside down, and didn't premix, despite there being a block-off plate installed. One of the pistons was overheated and black, and the motor was in a box. It was also missing the MPEM. Got that whole ski for $100.

 

[etemplet]

The 97 GTX I bought was running fine till he parked it. Said it might need a mechanic to check it out. It was locked up. I got it to run just barely after freeing up the engine. The only thing good is one rave valve and the starter everything else was SHOT. LOL I am preparing to build the engine in a few days. I got more balls than brains when it comes to buying mechanical stuff. But... even the stuff that runs isn't guaranteed to be worth a crap. I buy em' cheap an sometimes free wouldn't be a bargain. LOL I do love fixin stuff though. Lucky US !!

 

[IDoSeaDoo]

Well, that makes two of us. My fav is going in to see what killed it. The "Autopsy". Honestly, I think if you buy a "running" ski that's 20yo, you have no idea how much longer it'll stay running. These things are said to need rebuilds every 100hr. At least if I rebuilt it, I know what all's in it and trust it a lot more. The first ski I actually bought had a "good engine" and "ran" until the wrist pin bearing blew unexpectedly up and stranded me. Fun times.

 

[etemplet]

So the first ski I bought 1996 SPI started right up.... I mean instantly. I took it home and did the carb and gave it a lot of love. What I noticed straight away was that the oil pump cable was so loose the pump could not possibly have been providing any oil over the idle amount so I switched to pre mix. I took the ski to florida for the week and it ran great. Last day it would run bad after hitting some waves and I'd have to putt back to the shore. After letting it sit 1/2 hours it would do fine again... then same problem. I did some checking and sure enough the PTO cylinder was scoured really bad with the mag cylinder almost as bad so I did a new top end. Boy O Boy did I learn to HATE aftermarket pipes. I think the key to these skis are preventive maintenance and more preventive maintenance and lots of love.

 

[etemplet]

I bought a GTI once that was taken to a shop to have an SBT motor installed. The "mechanics" didn't remove the pump, rather slid the motor fwd, and estroyed 3 of the 4 motor mounts, installed the fuel strainer upside down, and didn't premix, despite there being a block-off plate installed. One of the pistons was overheated and black, and the motor was in a box. It was also missing the MPEM. Got that whole ski for $100.

I pulled the engine on my GTX without pulling the pump but I did remove the motor mount in the front. It came right out. Of course I'll have to realign but judging from the previous mechanical condition.. it is a good idea to do everything new. Ha ha.

I have yet to work on any of the pump side or even replace the pump oil. That is something I need to do on all of the skis.

You guys are so very helpful with all this stuff. Thanks so much for sharing.

 

[Mekanix]

LOL you're kidding!! They must've been slapping around in there like mad! Did it trash the pistons? I'd look into anything else they "rebuilt". Did it actually run with those pistons? What was compression?

I bought a GTI once that was taken to a shop to have an SBT motor installed. The "mechanics" didn't remove the pump, rather slid the motor fwd, and estroyed 3 of the 4 motor mounts, installed the fuel strainer upside down, and didn't premix, despite there being a block-off plate installed. One of the pistons was overheated and black, and the motor was in a box. It was also missing the MPEM. Got that whole ski for $100.

It ran !!
Ran well too with 150 psi each hold but did have some noticeable piston slap which was weird for a "new top end rebuild" but that was without water flowing through it.
Pull it apart and the cylinders measure 82.30 so it's only been bored once. Going to go to 0.75 over to to make sure it cleans up well.
On top of that the crank is shot. Connecting rod bearings are rough. Still original crank, so I'm not really a fan of those crank bearings.

Bunch of parts on the way. New crank, top end kit, engine gasket kits counter balance bearings... just wondering if I should stick to wsm stock parts or spec the whole thing out and make it perfect.. actually only thing I'd change is the base gasket and maybe rotary valve.

Looking to flip this ski I think lol. It's turning into another keeper lol

 

[IDoSeaDoo]

What crank did you use? I've had WSM crank break in half and total a case, 1 piston and 1 cylinder, as well as piss me off. This was back before I realized that my cooling drain hose off the T-fitting was totally clogged. The ski might have been running hotter than normal But regardless, I'm wary of WSM parts. This one had only 30hr on it.

 

[Mekanix]

I went with wsm because I've used 5 if their platinum top end kits and 3 of their cranks without fail so far. Even my own gsx is all wsm with nearly 200 hours on it so far. All wsm except the rotary valve. They can't make them the same as original. And the base gasket is seadoo 3-4 hole so I can get the right squish.

Where did it break?

 

[mikidymac]

Never used their cranks but in 25 years I have never had a WSM part fail.

 

[Mekanix]

I keep thinking that oem is the best to use and in many places I would stick with them but the aftermarket things I use are:
Wsm
Platinum piston kits
Gasket and seal sets
Crankshaft
Wrist pin bearings
Balance shaft bearings.

Oem stuff I use are:
STARTERS lol
Rotary valves
Raves and housings
Base gaskets sized appropriately for the build.
Mikuni kits
Oil.

 

[IDoSeaDoo]

It broke right in the middle, about 3" from the big end. Slapped around and windowed the block on both sides, and took a chunk out of the cylinder lining. Nastiest engine failure I've ever seen. Happened at WOT with 0 warning.

I will mention this: while it was a WSM connecting rod, it was remanufactured by some 3rd party. Could be they botched the reman.

Would you use a WSM crank on a highly modded motor?

 

[mikidymac]

On a highly modded motor I would stick with OEM.

 

[IDoSeaDoo]

My only beef with OEM is that they don't have oil holes drilled into connecting rods to oil the wrist pins (all other manufacturers do). I've had needle bearings blow up on an OEM crank. ProX rods are the best IMO, but are expensive to get on a crank. I wish ProX made whole cranks, but right now, you have to order the rebuild kit and have someone like Crankworx reman it for you.

How come HotRods quit making cranks for the carb 787? I was going to use them, but can't find one.

 

[Mekanix]

It broke right in the middle, about 3" from the big end. Slapped around and windowed the block on both sides, and took a chunk out of the cylinder lining. Nastiest engine failure I've ever seen. Happened at WOT with 0 warning.

I will mention this: while it was a WSM connecting rod, it was remanufactured by some 3rd party. Could be they botched the reman.

Would you use a WSM crank on a highly modded motor?

Mildly moded maybe as in pods and a head. But no more than that. I do like the extra oiling holes though.
I have had one big end and one connecting rod replaced in my sporster engine without a problem and that boat required lots of throttle all the time without any hint of failure. The shop I went to said they would only replace the rod and web if the rest as oem and still tight.

 

[Mekanix]

My only beef with OEM is that they don't have oil holes drilled into connecting rods to oil the wrist pins (all other manufacturers do). I've had needle bearings blow up on an OEM crank. ProX rods are the best IMO, but are expensive to get on a crank. I wish ProX made whole cranks, but right now, you have to order the rebuild kit and have someone like Crankworx reman it for you.

How come HotRods quit making cranks for the carb 787? I was going to use them, but can't find one.

Maybe wsm put them out of the business of making them cheap and available. I mean high quality means high price and the average person is going to go cheap first.

 

[IDoSeaDoo]

Yea, I tried to go cheap. Learned my lesson... Be wary of eBay remanufacturers. By the time it fails, they'll be long gone. Even if you get your money back for the crank, you still have a windowed block, damaged cylinders and at least one broken piston. It's why I'm doing some research before buying my next crank.

 

[mikidymac]

Hot Rod cranks were bought out by someone else a few years back and the quality went down. Most people will not use HotRods cranks anymore. If you check the other forums they have gotten a pretty bad reputation in the last few years.

 

[etemplet]

My only beef with OEM is that they don't have oil holes drilled into connecting rods to oil the wrist pins (all other manufacturers do). I've had needle bearings blow up on an OEM crank. ProX rods are the best IMO, but are expensive to get on a crank. I wish ProX made whole cranks, but right now, you have to order the rebuild kit and have someone like Crankworx reman it for you.

How come HotRods quit making cranks for the carb 787? I was going to use them, but can't find one.

How much does it cost to have a crank rebuilt by a quality shop?

 

[Ankeneyou]

You can get an OEM reman for $352, so I don't get why everyone uses aftermarket.

 

[etemplet]

Not to shabby on the price. I'd like to visit a shop and see how they do this kinda stuff.

 

[IDoSeaDoo]

You can get an OEM reman for $352, so I don't get why everyone uses aftermarket.

WHERE? Do you know if they check the balance on them, or just do run-out test? Who's the remanufacturer?

 

[IDoSeaDoo]

Not to shabby on the price. I'd like to visit a shop and see how they do this kinda stuff.

Same here! Ms. Frizzle, I think it's time for another field trip!

 

[etemplet]

Same here! Ms. Frizzle, I think it's time for another field trip!

I am a machinist by trade and have done a lot of things but this kind of stuff is interesting. LOL

 

[IDoSeaDoo]

I wish I had access to some machining equipment. I've been wanting to make some aluminum rave pistons for years now. Every time someone makes some, they want a ton of $$ for them. I think I will attempt to cast them out of Aluminum one of these days.