yamaha noob, sled isn't starting, cold compression...

[Scootdogydog]

Hey everyone...I bought an 2005 RX warrior with around 1100 miles on it in the spring. I'll have to post some pictures this evening; it's not all stock, but I'll have to let you experts chime in on what isn't stock/what I should upgrade...but first things first. I went to start it up on Sunday, and it wasn't starting. I found out that it wasn't getting fuel to either fuel pump. So, I disconnected the hoses from the tank, blew threw them, and put some fuel in a beer bottle , tried starting it up again...still no luck starting, but I had fuel into one fuel pump, so some improvement there.

I went ahead and ordered 1/4" fuel line to connect the output (the fuel pump that wasn't getting any fuel had a small hole). I actually put my finger over the input and could feel some pressure...I would think that this tells me the fuel pump is working; the vacuum isn't.

So, while I wait for amazon to ship my new fuel line, I ran a compression test. I borrowed my buddies gauge as I didn't have the correct adapter. He has a cheapo HF gauge. At his house, his '11 polaris assault 800 2 stroke that he claims is mint, had ~90-95 PSI cold compression in one cylinder.

So, I go home, and test my sled out. all 4 cylinders, 105-110 PSI on this gauge...cold (as it's not starting)

I thought that was all good considering I have a bunch of v8s around (correct crafts)..until a quick google told me stock would have been 230, and above 180 after some use would be good.

Anything I should be worried about with that compression? The unknowns are the gauge, and cold vs warm. I bought the correct adapter for my gauge, but that's not expected here until next week.

 

[MrSled]

Did you clean the carbs?.. also thats way low compression on that 2 stroke.. , should be 120 + that gauge sounds way off.

 

[Scootdogydog]

Thanks for the response. I didn't clean the carbs. I agree on the low 2 stroke compression, which is the main reason I'm a little suspect of the gauge accuracy. However, I know that ideal compression readings should be done with a warm engine.

Engine basics I get. Compression, spark and fuel make the engine go boom. So, with a dry inlet into the fuel pump, I don't think I have a carb issue, yet anyway.

Compression on my cold 4 stroke was 110ish, on a suspect gauge... should I be concerned?

 

[Scootdogydog]

 

[maim]

re-check the compression for your peace of mind but i think it should be fine with that milage but a shot of ring free would not hurt.

as mr.sled said, clean the carbs as i bet the pilots ore plugged with crap from the float bowls as the gas likes to evaporate from there if it is not run every 3-4 weeks in the off season. my 05 would crank for over a full minute if i did not start it often enough.

 

[thrasher]

Manual states standard compression pressure at sea level should be 206 psi, minimum 179 psi to max. of 230 psi after the engine has ran for several minutes. Obviously the readings will be lower on a cold engine. So recheck compression with a good compression gauge. Difference between cylinders should not exceed 14 psi.

 

[Scootdogydog]

Thanks guys. So, for starters, I'll clean my carbs tomorrow, get the new fuel line installed, and it should fire right up. I already ordered the correct adapter for my good compression gauge, so I'll get that checked early next week (slow shipping on that).

Anything I should be looking to upgrade on the sled? I don't like the non-original paint/graphics. I think the skis have been upgraded, maybe some other things...

 

[sxr70001]

Maim touched on it, but just to push the point. A lot of these sleds will lose their prime in the fuel system if not started regularly. There are many posts related to this, but basically people will pressurize the tank through the vent or fill the carb bowls manually for the first start of the season. I have had buddies ruin batteries cranking and cranking to get their sleds started before learning this. Good luck!

 

[DGZRT]

http://www.worldclasswraps.com/16-RX1-Vector-Yamaha-sled-wraps.html
That seems like a different color blue than I'm use to seeing , but I don't know much about RX1 .
I posted an example of a graphics wrap. I'm sure if you do a good search you can find one cheap!
I know I would clean the clutches and check the idler wheels real good . Change the oil and the Chain case lube.
Very nice ski's they should work great. The shocks look to be set right ( you want the "A" arms level ) maybe measure the sway bar. I believe RX handled better with a 13mm bar.
Barn of parts has the sway bars . Get the front off the ground and see if there is play in the front suspension . Grease it all up and pray for snow this year. ENJOY !

 

[Scootdogydog]

Can't thank you guys enough! With a little elbow grease, it was running. I'm going to add a fuel shutoff when I get around to it so I can run it dry; I'll probably fog it next summer as well. I'm really hoping the gauge was off; I tested two cylinders hot, and both came back with a reading on 90PSI...so 110 cold, 90 hot...hmm. That doesn't add up to me.

DGZRT -- thanks for the comments/maintenance items. I'll definitely get on that this weekend. oil and filter were definitely on my list, but I'll check the clutches and wheels, change the chain case lube, and get my grease gun on it. The previous owner painted it blue (it was red from the factory). I would have kept it Red, but that's over now.

I just measured the sway bar- 5/8" diameter or so, which is about 13mm.

 

[maim]

was that in the centre of the bar?

just run the motor with ring free in the gas as the rings are most likely stuck from sitting. heck it is not even broken in yet at that milage. needs another 2-3000mi before it comes close to being broken in.

 

[Scootdogydog]

the 5/8" was diameter in the center of the sway bar. Is that okay?

I ordered some ring free (never heard of that before). Should I run this continually, or just to start seasons?

 

[Al Bundy]

There is a "shock" treatment you can do with ring free. That process uses more all at once; If the can doesn't give you instructions just Google it. You can also use it every fill for preventive maintenance. I personally use seafoam.

 

[Scootdogydog]

Yeah -- i googled it. as with most products (sta-bil/seafoam, etc), there are mixed opinions about it actually doing any good, or being snake oil Nonetheless, it's a fairly inexpensive product to run, even if it has a small benefit.

the oil was super clean; I don't think the PO was out on it at all last year -- we had a horrible year for it last year. Many of the binding screws were stripped, with a few of them missing. I'm leaning towards an alan/hex head when I replace them.

While I wouldn't normally change the oil with it looking this clean, it sounds like I should sacrifice a few quarts of oil to change the crankcase lube, and check for any wear in the gears.

I also want to adjust the clutch when I inspect it. It seems like I have to give it a lot of gas in order to engage the drive gear.
Also up for maintenance: a brake pads, and rotor resurfacing.

I think i'll like the simmons flex skis on this; probably one of the best upgrades that was done to this sled.

I'm finding lots of good reading information on this site, and you guys seem like a great bunch!

 

[DGZRT]

I'm going to guess you do a lot of Water sking or you help with the local ski show. Nice boats !