bought a new unused 2004 550 sport touring in 2005.had it 38 miles engine holed,this was a common event in my provinceof nfld&[LABRADOR ],which is where i am.the dealer tried diff jets both mains and pilot,diff e clip positions,ignitions.polaris admitted there were problems after driving me mad about complaining.the only band aid solution was run way rich beyond stock but the performance was garbage and milage went way up.the machine bogged because of excessive fuel,the plugs were excessively sooty.polaris done extensive testing in gander but the results i could not find out.i think because polaris discovered the problem would be too expensive to fix,so everything was hush hush.i have to date had 4 engine rebuilds in 2500 miles garbage.DO ANYBODY KNOW ANYTHING ABOUT THE REAL FIX . WHAT ABOUT WHEN THE WARRENTY EXPIRES AM I STUCK WITH A LEMON AND ALL SORTS OF EXPENSES,EVERYTHING DOCUMENTED. PS POLARIS SAID THE TOLERANCES WERE TOO TIGHT ,NEW AFTER BREAKIN SHOULD BE 3 TO 3.5 THOU NOW THEY SAY 4 TO 4.5 THOU SO AFTER THE BREAKIN THEY HONED TO THE SPECS IF NOT THERE. ALL BULL #### HELP!!!!!!!!

Don't know what to tell you. We had a 03 550fan, absolutely no problems, have a reputation for being bullet-proof. There is a dealer not far away that uses 550's for his rental fleet, year after year and they get the crap beat out of them.
Something's just not right in your case. What are they blaming the engine failures on?

Don't know what to tell you. We had a 03 550fan, absolutely no problems, have a reputation for being bullet-proof. There is a dealer not far away that uses 550's for his rental fleet, year after year and they get the crap beat out of them.
Something's just not right in your case. What are they blaming the engine failures on?
[/b] they had nothing specific but the most they say is to drive the machine like i stole it,not to cruise around but its a touring so thats what its ment for.i could not get the reasons from polaris or the dealer other than they dont know but i dont buy that

The 550s are an improvement is some ways apparently, though I am at a loss to identify exactly what they are other than more horsepower. What I can say with assurance is that the folks who use them as work machines like they did with the 440s and 488s that preceeded them are not finding reliabilty to be one of the strengths of the bigger fan engines.

The early 550s were known and admitted to have some problems which were corrected through recall procedures. As much as the engine gets tweaked here and there continuously, year after year, I'm thinking the factory knows that the 550 is still a few screws shy of being "bullet-proof."

A couple of days ago I got a call from a buddy who was looking at his '05 RMK engine and wondering what, exactly, he should do to get it running while he has the cylinder bored over on one side. His rig munched the intake side piston skirt with only 6500 miles. He's a trapper so he's not especially hard on his equipment, pulls a light sled and gets lots of miles but no real heavy pulling. His was not a case of "burning" a piston like the earlier 550s were prone to do - and that seemed to be especially true of them if they were run somewhat easy, as in in cruising around. It's not the first piston he's munched either. It's his third 550 - his first a '99 RMK - and I think he's had the same problems with all of them. Fuji does know how to build solid fans. I'm not sure what they're doing wrong with the 550s but something is clearly wrong. I suspect it matters little since nearly the whole market is now recreational and Polaris seems to be geared only in that direction. Apparently the philosophical differences which split the company years ago still exist in some form else 'Cat might have done the same. Thank goodness for the guys in Thief River Falls else the utility portion of the market would be sadly pretty weak now.

So, to give you my take on Polaris' fix for the 550: AC Panther or Bearcat 570!

Wow. In all the post's I've read over the years, the 2000+ miles we put on the wifes sled before selling and the info I received from the local dealer with the rental fleet, this is the first I have ever heard of the 550 being a problem engine.

neighbor had a crank problem with a 550 last year because of lack of oil but other wise bullet proof

The '99 550s had issues with cracking piston skirts and midrange lean conditions but for the most part I have heard of very few problems with them.
I had a '99 550 SuperSport and it was rock-solid reliable.

bought a new unused 2004 550 sport touring in 2005.had it 38 miles engine holed,this was a common event in my provinceof nfld&[LABRADOR ],which is where i am.the dealer tried diff jets both mains and pilot,diff e clip positions,ignitions.polaris admitted there were problems after driving me mad about complaining.the only band aid solution was run way rich beyond stock but the performance was garbage and milage went way up.the machine bogged because of excessive fuel,the plugs were excessively sooty.polaris done extensive testing in gander but the results i could not find out.i think because polaris discovered the problem would be too expensive to fix,so everything was hush hush.i have to date had 4 engine rebuilds in 2500 miles garbage.
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I think it's time to take the sled back and tell them to give you a discount on a different sled for the amount that you have paid for this lemon. If they refuse, get a lawyer.

I think it's time to take the sled back and tell them to give you a discount on a different sled for the amount that you have paid for this lemon. If they refuse, get a lawyer.
[/b] they would of taken it back after the second engine but only the book value .at that time it would of been nearly 2 thou dollars off the orginal price plus lose the taxes with only 500 miles on her at the time.it was an awful price to learn of industries mistakes at the expense of the consumer.it should not be allowed.

Push harder on your dealer/Polaris. They don't want stories like this getting out - so tell them you want it to be resolved or you'll get a lawyer involved. The last thing Polaris wants to do is spend money on legal actions when their product is obviously a lemon (in this case). Sorry to hear about your troubles - I have always had great luck with Polaris and my local dealers.

Polaris knows that the 550 fan is a more problem prone engine than others they've built. They may not admit it - and I doubt that any company would- but I'm sure that they know that. The many changes that have been made to the engine are strong evidence that they have needed improvement. That isn't a bad thing - I'm actually glad that they are so willing to refine and engineer an engine which, I think, should never have hit the market when it did. It wasn't ready then. That has left them in a position of having to "catch up" the product to where it should have been when they introduced it. The early 550s had so many problems that one of the major marketing distributors in Alaska refused to sell the 550 fan for a time from what I understand.

That said, most machines will give some good service unless they are lemons as the machine mentioned in the original post seems to be.

It was fairly normal for the older 440 and 488 fans, used as work machines, to get at least 8000-10,000 miles without any sort of engine work done to them and some even made 12,000-15,000. Of course the tolerances they had by that point were such that they did not have the same power they would have had when new. They were good reliable engines though. The 550 is simply not in the same league. As recently as this past weekend, when I had the choice between a 488 fan with 19,000 miles (original pistons - 6000 mile rings) or a 550 with 3300 miles on it (3rd piston on one side), which do you think I chose? Well, I could have used my wife's 440 Panther with 5500 miles too, I guess, but I have some loyalty. So what did I use to explore the 340 miles of largely trackless terrain, pulling a sled to boot? Yep, the '97 Trail RMK with 19,000 miles because I know it to be a reliable rig- and it performed flawlessly.

This is the first thread I have ever read online about the 550 engines blowing up.

Most people have never had trouble with theirs, and if they have, its been stuff like, "bogs when warm" or "fouls plugs if it idles for more then 5 minutes" or "rejetted for better top end".

I do not believe in lemons.

Iron is Iron, metal is metal, simple phsyics, there is no lemon juice involved. If you are replacing all the parts with stock OEM parts, and it's still blowing up on you, the original problem has not been addressed yet.

If your having this must trouble with yours, the problem, quite simply, isnt getting solved.

The dealer is too quick to address the problem they saw (the melted pistons) and not the invisible problem (whatever caused this?).

1) After the rebuild, listen for knock and pings, I broke my 550 in on premium, and I could still here it pinging, although its good now. If your engine holed, in 38 miles, then you should have some warning signs, like massive knock.

2) Check the cylinder head temps after a run.

3) Check for plug indications of a carb problem.

4) Check the oil injection system is working properly.

5) Check the fan, the blades themselves, and the shroud to make sure nothing is blocking the air flow, and check the plugs for lean like symptons.

The 550 is a good engine, lots of storys of 10,000 miles+ rentals with no problems. I know quite a few people who have modified their, throughout the forums. I have a friend who has one with 38mm carbs on it, clutch kit, AEEN pipe, and a SLP Air box... 3000 miles since and its running great. Look around for some other reviews on the net if you don't believe me.

These sleds due have a specific breakin procedure. 2 pints of oil to the first tank of gas. You CANT cruise with it, you HAVE TO vary the throttle continually and WOT only for short bursts, for the first 300 miles, and like I said, I would run premium until you don't hear any more pings or knocks.

That being said, good luck with the diagnosis, remember there is no difference in the engines from 03-06. 2003 was the big year for the 550 (digital timing, bigger exhaust etc).

-Steve

This is the first thread I have ever read online about the 550 engines blowing up.



-Steve
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There has been lots on the net about the 550s not being reliable :sly:

Yet there are some that have been reliable as Cory9 mention his