Sleds won't start. Now the engine is down on compression!

[schmeg]

LB is right. Its some outside factor, not the motor. The motor has had years of development in bikes.

 

[rxrider]

way off on what exactly? slydog?

2 through 6 actually

rxrider

 

[rxrider]

7) I fully agree on

Glad she's up and running, bad when bad things happen. BTW it was not a catastophic failure, think snow .

 

[CENA]

I would agree it is the dealer. Dealers are falling behind on the technology of these sleds and need to have continual training to keep up with being able to work on them and diagnose problems. Too many dealers think they know it all and will make up stories because they couldn't figure things out. Hence all that labor you spend on them trying to diagnose the problems. My 2 cents.

 

[rxrider]

CENA - you're right on dealers falling behind on technology....

I'm glad my dealer have been a mechanic on a Yamaha YFZ R1 Superbike team racing in the Nordic series in the past. The dealers need to learn to wrench these motors, the Genesis 4stroker need far more experience to wrench and diagnose than a 2smoker.

danq - I hope you got your sled repaired.

 

[rage man]

Again, try to listen. Its a BAD DEALER.
It is NOT POSSIBLE for at least one valve in all 8 cylinders of your two sleds to suddenly stick simultaneously. It doesn't happen EVER. Maybe ONE valve between the two sleds, but definitely NOT 8+.

This is NOT 1 in a million, it is IMPOSSIBLE.
You have a BAD DEALER.



Also, pay close attention to this;
It hasn't happened to anyone else. That means that there's nothing wrong with the design of the valves. That means that it was something ELSE.

i agree totally

 

[danq]

i had the same problem on mine and the wifes 06 apex rtx. came home from da up and the sleds sat on the trailer for 6 days before i got to clean them up. motor spun like there was no compression. held the throttle wide open, and both sleds eventually started. didn't have a problem after that. 4000 miles on one 2300 on the other. greatest sleds i have ever owned. they all have little problems. it's a machine!!!!!!!!!!!!!!!!!!!!!

thanks scooter1, that comment is helpful. I can try that next time.
Dan

 

[danq]

The other "bad dealer" comments are less useful because no one suggested another reason why both sleds wouldn't start and were low on compression. If you think the dealer is bad, what do you think they missed?

Sorry, I guess when someone says their sled won't start, what's wrong? and the answer is "dealer bad listen to me"... just doesn't help much in my opinion.

Please don't take this wrong, I appreciate the expertise on this board a great deal, includeing everyone who responed to the thread!

 

[LazyBastard]

Its impossible to say what they missed. The problem with them is that what they said is IMPOSSIBLE. Any number of things could cause two sleds to simultaneously not start, starting with the effects of temperature. Lets forget about the whole "stuck valves" idea and think more along the lines of FUEL and ELECTRICAL systems. These are the two systems most easily affected by environmental conditions. Were there air bubbles stuck at some point in the fuel system? Maybe some relay got stuck? Or some water (condensation) got into a relay? There are literally HUNDREDS of SIMPLE things that are much more likely to go wrong on two sleds simultaneously.

 

[Mongo 1]

I really hate to jump into this thread, but after reading it for the last hour I can't help myself. Let me think about this eight exhaust valves, times two. Twelve intake valves, times two. I can buy a few valves contaminated by carbon, or corrosion. I just don't know how ring free was applied to the valve stems to free them up, especially the exhaust valves. If it was carbon on the seats, (unlikely since they were running when you parked them) a few revolutions should dislodge it. You also stated that the compression was 55 psi, was that across the board or the only cylinder of eight that had any compression. To reach 55 psi the valves on that cylinder at least would have to be seated, but possibly leaking. I hate strange situations like this, I'll be checking my attak tomorrow.

I hope that you don't condemn the snowmobiles so quickly. In my opinion they offer the best overall package. I hope this is your last major hurdle, and all that matters is they are running again.

 

[danq]

Thanks LB thats more clear to me now, but how does that affect compression? I guess we could "assume" the compression test was not done, or done incorrectly.

 

[bdm]

The other "bad dealer" comments are less useful because no one suggested another reason why both sleds wouldn't start and were low on compression. If you think the dealer is bad, what do you think they missed?

Sorry, I guess when someone says their sled won't start, what's wrong? and the answer is "dealer bad listen to me"... just doesn't help much in my opinion.

Please don't take this wrong, I appreciate the expertise on this board a great deal, includeing everyone who responed to the thread!

Actually, I think that the advice will be helpful, because when you go to a dealer (that has a clue) for future work, they will more likely properly diagnose your problem and give you the reason that the new problem happened.

It may be too late to learn the mechanics of this problem; but, the advice may be of value for future problems.

 

[rightarm]

Have you ever used race gas in these sleds?.Prehaps the fuel injectors themselves are gummed up.

 

[watersuper]

My guess on your problem is the compression has always been fine. An electrical problem seems more appropriate. Good luck and hope you don't see this again.

 

[RTX]

The other "bad dealer" comments are less useful because no one suggested another reason why both sleds wouldn't start and were low on compression. If you think the dealer is bad, what do you think they missed?

Sorry, I guess when someone says their sled won't start, what's wrong? and the answer is "dealer bad listen to me"... just doesn't help much in my opinion.

Please don't take this wrong, I appreciate the expertise on this board a great deal, includeing everyone who responed to the thread!

Dan
While i understand your frustration i also think you need to read back from page 1 thru 8 all over again.
I can tell you that i posted on page 2 that i felt the problem was the dealer and why.
throughout this post there has been numerous posts of why we think the dealer is at fault. I even suggested calling the better business burea. you could have asked them about complaints logged against the business. they are normally more than happy to work with you to. this is an important and handy tool to determine the satisfaction of a dealerships customers.

Yamaha has issued a bulletin suggesting the proper way to test engine condition. they claim a compression test on these motors can often give faulty or misleading results and because of this they suggest doing a leak down test instead. this service bulletin can be found at www.snowmobileworld.com
you will need to join up as a member to view this info.

I honestly am not trying to come off as a jerk here. Ithink you need to look at the situation from an outsiders perspective.
I understand that you want to believe your dealer but you also need to understand that your dealer is in business to make money. the last thing a dealer is going to do is take a loss on a repair if he thinks he can lie his way out of it.
I am truly sorry for the problems that you went through and hate to see a member of the yamaha team down on his luck. I wish you all the best of luck with these sleds and i am positive you will restore your faith in these sleds and grow to love them as much as all the other guys on this site.