check your pistons before assembly =)

[starter kill]

last year i tore my stock motor apart went with a SBT crank that was trued and welded, pro-x pistons that were bored one over from stock. everything went well, ran great.


untill......


this past jan, i started to build my motor up. ADA head 35 cc domes, msd enhancer, factory pipe lmt chamber, hooker prop ect ect ect.

geting to the point, i didn't want to build all this on the pistons/cylinders from last year without doing some minor hone work. called all over looking for new rings, no-one had any, only place i could find some were in europe. screw that, so i pitched out some more cash and just got two new pistons *same size as before* they came in, i had all my parts, so i put the motor together. broke the motor in, ran for a few hours and this is what my end result was. 150 psi front cylinder 179 rear cylinder. WTF!?!?! so i got pissed, pulled the head off and about puked. the front cylinder was STOCK bore, did not have any etching on it, unliked the other piston (0.25) luckaly, i was able to salvage the rings, and put them on one of the pistons i used from last year, put it all back together and comp came up. 170 front 179 year. going to run it tomorrow and see if it seats.




i went back, and checked the boxes the pistons came in, and they were identical. all the numbers matched, all the part numbers matched. so, some dumb ass packaged the WRONG piston! i know, i know, i should have checked the piston it's self before install, but damn... you shouldn't have to. both boxes were sealed with the tape over the side from the factory, or wherever they make them.


this is just a warning for anyone that use's pro-x
check yer !!!

ima go with something diffrent from now on....

ok, rant over.

 

[NathanMoore]

i know, i know, i should have checked the piston it's self before install

Well that definatley sucks you got a wrong piston. But...I don't know how you could assemble an engine without knowing, or checking. When checking the arrow on top for piston direction you should have seen it, and I guess you didn't check ring or piston clearances?

Are the rings standard or .25?

I'v used hundreds and hundreds of pro-x pistons without incident, but things happen...a mis-package is hardly deserving of saying pro-x sucks. Im sure if you had checked before install (and yes you should with every brand piston), and called your supplier, they would have tried to fix the problem asap.

 

[Jayski]

Mate buy the sounds of what you have been telling us, you shouldn't be building your own motor's and blaming a parts suppliers because you don't know how to check your engine parts..

I have built a bunch of motors with pro-x as has 100's of other people on this forum, and not yet once had a problem, with any of the motor's..

You have made yourself to look like a total doosh bag to be polite.. Invest in a micrometer and it could have saved you building your motor for a 2nd or 3rd time..

 

[Patrick Star]

Dam SBT. :wall:



J/k

 

[egbrig]

Part of the learning curve. You'll do it next time, its part of the learning cycle. We buy parts, install without checking them out because either don't know how or get too lazy. When things go wrong we blame the seller, part manufacturer, and its hard to take responcibility. I agree with Jayski, you need to check the parts out yourself. Trust me, we all have been bit. We either learn how to check the part, pay a pro who knows how to or keep screwing ourselves. You need a bore guage and micrometer. Check ring gap too. For those who say they don't, well then know you know who doesn't know.

 

[Pablo]

I agree that you should check your parts, but c'mon guys. If everyone who's chimed in has never had a problem with mislabeled pistons and pro-x has been fine for all who've used them, then I bet most of you wouldn't check those pistons with a micrometer. You should check them (I agree 100%), but if you can't trust what's labeled on a sealed box and is brand spanking new then what do you have to go on? Let the guy vent and agree he'll check it next time. I don't think he comes off as a "douch bag." I've had a hundred times where things don't line up or parts are a bit off from OEM and I wanted to take a hammer to my ski...more often then not it was me who was wrong and not the part's fault for not fitting, but give the guy a break. He just rebuilt his ski with hard earned dollars and was ready to hit the water for some fun.

 

[nightrider05]

I agree that you probably shouldn't be building your own engines. Or if you do and are taking shortcuts then you should expect premature failures.

Pro-x pistons are as good as OEM pistons. Haven't heard of any issues with them.

 

[WFO Speedracer]

Mislabled or not it takes all of two seconds to stick the piston in the bore and see how much it rocks back and forth in the bore, I learned a long time ago to not take anything like that for granted, I have had machine shops bore cylinders 1mm over the size of the actual piston, bored cylinders come back with excessive runout or out of round, cylinders bored to the wrong clearance specs , you name it I have seen it. Thank God I have a cylinder guy now that I don't have to check behind, its right first time every time because I take it to someone who knows what they were doing.


PS I have never had a problem with a Pro-x piston or even a WSM piston for that matter, cylinder setup ,clearance checking and port chamfering are everything when it comes to piston life.

 

[Waternut]

I will say I that I check one piston for clearance and I check ring gap but I don't check the two pistons to ensure they are exactly the same. On the other hand, if one piston was etched and the other wasn't, that is really something you should've picked up on.

You have to remember that if you packaged 100's of these things a day, it'd be extremely easy to mess one up. I'd be willing to bet the piston was packaged and the label was put on afterwards but the guy didn't realize the next sheet of labels was a different size. He made a mistake, you made a mistake. You can make the argument that he should've been more careful and he can make the argument that you should've been more careful. It sucks that it happened but you are just as responsible as they are. You can call Pro-X and see if they'll do anything for you. They make send you another piston for free.

 

[ryan]

edit

 

[ryan]

what he said

Mate buy the sounds of what you have been telling us, you shouldn't be building your own motor's and blaming a parts suppliers because you don't know how to check your engine parts..

I have built a bunch of motors with pro-x as has 100's of other people on this forum, and not yet once had a problem, with any of the motor's..

You have made yourself to look like a total doosh bag to be polite.. Invest in a micrometer and it could have saved you building your motor for a 2nd or 3rd time..

 

[starter kill]

so this was definantly my first motor build, so i made a mistake. OOPS dang, was just thowing it out there to be careful and check your pistons, thats all. lesson learned.


oh btw, comp in both cylinders is 175 front 179 rear. will get the right piston with new rings this week and re-hone.


thanks for everyone bashing me.

 

[5810]

kustom

 

[badboyr6]

dont worry about it bro..some people on here think the world spins around them, its no big deal, just money! goodluck with the build once you get the right piston in there! let us know how it goes..and for everyone else..cut the guy some slack! , if i made a mistake like that id be afraid to post on here due to the bashing..but then again..i dont give 2 cents about what people think!! GOOD DAY SIRS!!

 

[WFO Speedracer]

Just a word of advice , next time do not use a thread title that invites bashing then change it after you get bashed, its kind of like starting a fight with a bully and then whining cause you got your ass kicked.

 

[GIL]

Hey, the way I see it you have entered the learning curve zone which ain't a bad thing! Welcome to the club. I love learning chit the hard way. lol

 

[WFO Speedracer]

Hey, the way I see it you have entered the learning curve zone which ain't a bad thing! Welcome to the club. I love learning chit the hard way. lol

Some learning curves are steeper than others.

 

[Waternut]

Some learning curves are steeper than others.

At least the guy admitted defeat unlike so many others that will argue their case until the thread is gets locked because it became a flame fest.

 

[WFO Speedracer]

At least the guy admitted defeat unlike so many others that will argue their case until the thread is gets locked because it became a flame fest.

You would have a valid point, that is if he hadn't started another thread over at PWCT.

http://www.pwctoday.com/f11/warning-pro-x-sucks-276156.html

http://www.pwctoday.com/f11/warning-pro-x-sucks-276156.html#post2667921

 

[starter kill]

You would have a valid point, that is if he hadn't started another thread over at PWCT.

http://www.pwctoday.com/f11/warning-pro-x-sucks-276156.html

http://www.pwctoday.com/f11/warning-pro-x-sucks-276156.html#post2667921

Just a word of advice , next time do not use a thread title that invites bashing then change it after you get bashed, its kind of like starting a fight with a bully and then whining cause you got your ass kicked.

yeah, i have two accounts? so what? i changed the name because yeah i did notice that people DO make mistakes. no biggie, all this post was about is to dubble check everything because i DID NOT. i really don't know what your problem is man, go ride your ski maybe it'll make you feel better. have a coke and a smile.