URGENTLY NEED HELP! 2003 Rx-1 bog/studder problem

[LazyBastard]

Stabilize the fuel? I emptied the tank, and ran it out, and put half a gallon of fuel in every 2 months and ran it through. I use 91 octane because it burns cleaner. I know that the higher the octane, the higher the flash point is.

And how bad is it revving your sled to 5000 rpms without a belt for 3 seconds for the primary?

It most definitely does NOT burn cleaner. It burns DIRTIER. This is because it doesn't burn as completely. The result of running too expensive a fuel is carbon buildup on everything. It can result in plugged rings and high oil consumption.

 

[RaWarrior]

There was an article in SnowGoer this month about running premium octane fuels. To sum it up, it basically said what most people already know. If the motor calls for premium, use it for maximum performance. If not, you're wasting money and actually losing performance. And nearly all modern motors calling for premium run fine on regular due to sensors that adjust timing accordingly.

Premium does have a higher flash point, meaning it is less likely to detonate from pressure alone. Simply put, the more octane, the more resistant the fuel is to pre-ignition, or lighting before the spark. Combustion before the piston is at TDC makes "ping"(vibration against the cylinder walls) and is bad for the motor, since the explosion tries to shove the piston down while it's still going up.
Now in a "standard" compression motor designed for regular 87 octane, the timing is ideally set so the compression of the cylinder brings the gas mixture just shy of it's detonation point, so when the spark fires the mixture is at it's most volatile. Now running 93 octane in the same motor, the gas mixture is not as volatile at TDC, it still could be compressed a lot more to reach the same volatility . So the explosion will be LESS POWERFUL than an 87 octane mix. But run 87 in a motor designed for 93, unless it has knock sensors, the fuel will detonate from the higher compression before the spark, so the ECU would have to retard the spark to compensate.

I'd lose the premium. Save money, and the eventual hassle of crap build-up in the motor from incomplete combustion.

Fill the tank completely, and add stabilizer. Run the motor (or go for last ride) to circulate the stabilized fuel into the carbs. Shut 'er down and leave it. All I've ever done and never had any issues with crappy carbs or hard starting. The "add a bit and run it dry" leaves the whole tank to collect condensation, and even running the motor till it runs out of fuel leaves some gas in the carb that can get gunky.

I'd like to know where the "premium burns cleaner" myth started. It doesn't. It doesn't contain "more energy" either, I've heard that a lot also. It does burn "cooler", but only because there isn't as much power coming out of the fuel, and again, the engine is designed to run a certain temperature. I know lots of people that believe this, and insist on putting premium in everything from weedwackers to cars. Just because it costs more doesn't mean it's better.

Rant mode OFF, I just don't get why so many sledders have a hard-on for premium gas based on the pretend belief it makes them faster or cleaner.

 

[RXWON]

Where are the 4 little screens in the picture a few posts back?

 

[extremefilms]

Problem solved.

We picked up a nice used set of carbs off of a running rx-1, as well as a cdi, and computer module, all for $120. First changed was the carbs. The problem consisted. Well, we removed the CDI, and the prongs on it were broken. We changed it. Problem still consisted. Changed the computer module finally. Problem solved. Now revs up insanely fast.

 

[RaWarrior]

Good to hear you got the problem resolved. These things rev like a F-1 racer, I'm still amazed how quickly they pick up for a 4 cylinder 4 stroke. Even stock, it's like they have a turbo on at all times. Crazy. Leave it to the Japanese to make motors this good.

 

[Sled Dog]

Two gallons of aviation fuel prior to putting the sled away is supposed to be the answer to this ethanol fuel degrading through the summer. Aviation fuel still has lead in it and nothing can grow.

 

[Rockmeister]

Stabilize the fuel? I emptied the tank, and ran it out, and put half a gallon of fuel in every 2 months and ran it through. I use 91 octane because it burns cleaner. I know that the higher the octane, the higher the flash point is.

And how bad is it revving your sled to 5000 rpms without a belt for 3 seconds for the primary?

It most definitely does NOT burn cleaner. It burns DIRTIER. This is because it doesn't burn as completely. The result of running too expensive a fuel is carbon buildup on everything. It can result in plugged rings and high oil consumption.

100% Agree.

I have a friend that just replaced his fuel pumps for the SECOND year in a row!
They are $80 EACH, he has 2 rx-1s x 2 each = 4 pumps.
That's $320.

He drained the fuel and ran it out both years. All pumps failed both years.
Simply stabilized mine ran it a bit and start it a few times over the summer.
I would definitely say (As Rawarrior said), leave the fuel in it!
Have replaced zero pumps in the same time frame myself.

 

[Len Todd]

If you empty the tank out, there will be moisture that forms. Better to keep the fuel in it and stabilize it. I too run the sled a few times in the summer. When I do, I bring it up to operating temperature. This is good for the seals, etc. I run a little seafoam through the sled now and then in the winter. I also run RingFree all the time. Once a year, usually at the eginning of the year, I shock treat it with RingFree. Then I change oil and filter.

If you have just a tiny bit of fuel left in the tank, it can easily dry out and flake. The flakes will plug the carbs. By the way, I have never had the Carbs off yet, knock on wood!

These sleds are designed to run on 87 octane. Higher is NOT better. LB is dead right on this issue.