warm starting problems

[hovermn]

My '03 Polaris 550 fan starts cold after 2-3 pulls, every time. Never had a problem starting the engine cold. Starting warm, however has proven to be a major problem, and pain! If it's been sitting for 10 minutes and up to 2-3 hours (longest I've let it sit before starting warm) it just doesn't want to start up. It seems to flood out right away. It usually ends up taking 15-20 pulls to get it started again. When out on the lake, it's not only embarrassing, but really frustrating and a little stressful. After all, I just bought the sled and I worry that I bought a POS.

A couple of days ago, I starting pricing the cost to install electric start on the sled. $500 plus around $150-275 for installation, depending on the shop. YIKES! The last shop I called was Forest Lake MS. There, I talked to a woman in the service shop and told her what was happening. Right off the bat she mentioned that I should turn off the fuel every time I shut the engine down. She was saying that fuel will continue to flow into the carb and cylinder after shut down and create an instant flood condition which is inherent to Polaris.

I haven't tried this yet, but I'm curious if this is true? Could something else be happening here? Why wouldn't Polaris do something to solve this problem?

Any thoughts? I'm really frustrated. I bought a pannel mount fuel cut off valve if this is the case so I don't have to open the hood every time, but I'm hoping there's something else going on here.

[hanson]

Not quite sure of your problem but the only way fuel can continue to flow into your carbs is if the fuel inlet valves (needle & seat) are bad.

Once the float bowls are full of fuel, and the float rises to the top, the fuel inlet valve closes and no more gas will enter your carbs.

Might want to check on that.

Otherwise, you aren't choking your sled again for a warm start are you?

If you do flood, give the sled full throttle and start pulling.

[jiganator]

Hanson has it right on.

Try holding the throttle wide open while pulling it over. As soon as it fires, release the throttle ASAP!

A jack stand would be your safest bet when doing this.

This test will help prove you have a flooding problem, as the sled should start sooner with throttle full open.

New needle and seats, should fix the problem

[Macgyver55]

It could be something as simple as floats being set too high and allowing gas to slightly boil or seep into the engine after shut down, or on the other end of the scale it could be a low compression problem. After testing the fuel shut off trick, the next thing I'd do is check the compression. That is easy enough to check with a compression gauge and a few pulls on the rope. I don't know the spec on your particular motor but 130lbs is enough for decent starting. ( more is better to a point) When my last Skidoo had about 14,000 miles it had dropped to about 115lbs and got pretty tough to start when warm. A set of rings and it was good to go.

For your sake lets hope its the floats....

[ChuckN]

Good advice here.

I'd say check compression first. Honestly, not to scare you, but the IMO the 550 fans by Polaris have had issues, major issues. I've talked to owners of these new engines blow with 100 miles...rebuild and blow piston(s) again. Maybe a fluke, maybe not, but when a local mechanic told me the same thing.....

However, I had a sled that had the very same symptoms and it needed the carbs rebuilt, replace needles/seats of the float bowl and clean the jets.

Just be sure to warm up these engines before blasting off into the abyss.

[hunterlaker]

I would bet its the needles and seats in the carbs..I have had the same problem..I just turn the gas off.

[hovermn]

Thanks for the info guys! Sounds like there's a lot to digest and check over here. First thing's first, check compression. Something I was going to do before buying the sled, but completely forgot about when the time came. DOH! As far as the carbs are concerned, is there an easy way of checking this? As I've stated in other threads, I'm brand spanking new to snowmobiles and hardly know the first thing about these things.

Hanson, you mention choking a warm engine. If I felt that the engine was warm, say within 30 minutes to an hour, I would start pulling the rope without the choke. If after 2-3 pulls, I would flip the choke to half. Eventually, after juicing the throttle once or twice, pull rope, repete many times, it would grumble back to life. awk

Chuck, you comments about the engine shocks me a bit. I've heard nothing but good things about this engine from everyone I've talked to. Are the instances you're referring to isolated or pretty wide spread? I believe you, but you're the first one to speak negitively about the engine. I'll surely heed your advice about proper warm up, though! Good advice!

[MikeYager - Suzuki]

If its warm and you dont get it started in a few pulls open the throttle all the way to get it firing. You'll need to stay on the throttle and play with it until sled clears itself. I'm not going to guess why you are flooding. Save yourself some aggrevation and take it to a reputable dealer. They sure arent busy now.......

[ChuckN]

I'm not a hardcore Polaris guy, but a conversation with a disgusted owner and mechanic said he's seen a few of these machines with problems.. I'd say isolated since I don't talk Polaris much... Again, didn't mean to scare you, just stating a compression check is a start as it's very quick and easy before digging deeper.

There's no easy way to check the carb situation. Basically take carbs out of the sled, take the bottom bowl (pan) off the bottom of the carbs and work on the jets. Personally, if compression checked ok, I would just replace the float needle jet assembly. A sled that is 3-4 years old, and the previous owner who may have neglected to properly store the machine in the off season...damaged carbs can easily happen.

I guess some Polaris' carbs are sensitive to trailering also. The bouncing on the trailer damages the needles/float assembly, and gas floods into the carbs. Before trailering it may be wise to shut off the fuel valve, run the sled for a little while to run gas out of the carbs a bit. Kinda like the advice the dealer gave you.

Good luck!

[hovermn]

Just checked compression. 125 psi both cylinders. For reference, I checked the net and found this to be normal.

Chuck, I also checked the net for the troubles you talked about. Yup, found'em. However, from what I could find, it sounded like it was the earlier models that gave the most trouble, say 99-02. Didn't find anything on the '03. Maybe I just didn't uncover it.

Next on the list is probably putting the sled up on the block. I say this for a few pretty vaild reasons:

1. I bought the sled for ice fishing. So far, no snow means no sled. I didn't buy the sled to be a trailer queen.

2. Reading about the many many many problems Polaris has had with the 550 fan, it may not be a bad idea to sell the sled while it still runs, and it runs great!

3. I start a new job next week (OFF 3RD SHIFT AFTER 10 YEARS!!!) and will take a pretty hefty pay cut.

Both 1 and 3 put me on the fence with selling the sled about a week ago when I accepted the job. I think #2 just pushed me over. If I keep it, I could get thousands of trouble free miles out of it. However, it could blow during the next outting. With the pay cut, I'm SOL if that happens.

Wow, didn't expect this when I started this thread. *Sigh*

[hovermn]

Of course, I could just gamble it and run the thing for a year... I sware I'm Bi-poler sometimes! lol

Either way, you guys have provided me with some good info here. Thanks!