88' 250 TB - Fuel line diagram???

[stuff4mason]

Well, the TB won't start. My newly aquired machine ran great at the sellers home, but doesn't like my house.

Fuel was dumping from the carb and into the airbox. I took the air cleaner off and started checking the carb. It appears there was two fuel lines on the carb at the time - 1) the main fuel line in and another line which went no where, but had evidently sat on the exhaust and melted in half.

Then, I notice another line coming from the crankcase - I assume this is your pressure line for the tank, but it wasn't hooked to anything.

I took the gas tank off, and there were two more lines running up the bottom of the frame rail. One went into the frame and just ended. The other seemed like it was just laying there.......ERRRR...Why can't people put things back together as they were meant to be?

I took the carb off and cleaned the H**l out of it. I'm ready to put it back on, but have no idea where all these extra lines go. FYI - Someone took the oil tank off this thing, and the previous owner said to pre-mix the gas. Are all these lines for the oil tank, which doesn't exist any longer?

I checked on the polaris parts website, but the diagrams don't show fuel lines. Does anyone know where these all go, or could someone look at a non-chopped bike and tell me? I sure appreciate it!

[LarryWannamaker]

The only lines on the carb for fuel are the fuel line from the tank and then the thin overflow line (probably the one that melted)... Other than that there is no other...

Make sure the carb is clean and the floats are set....
The other lines must be for the oil injection... I'll check mine when I get home later today and see where it was supposed to go...

Good luck!

Larry

[Manaen]

yeah as larry said there is only one fuel line. The other lines are breather lines and overflow lines. You need to replace the melted line and clean the carb. All the breather lines should be run up high to a dry location. The drain lines on the bottom of the carb should be run down so fuel can drip out of them. They all need to be clean and free flowing. Sound like there was dirt in the tank and it clogged your needle seat inside the carb. This will make the float not able to turn off the gas flow when the bowl is full and will overflow (as you've noted).

bottom line...
Clean the carb and install a fuel filter in the line from the tank so it does not happen again.

[stuff4mason]

Thanks guys.

Two quick questions:

1) As I said above, the oil tank was removed. So, is it safe to run a fuel filter with oil mixed gas? There isn't a filter currently on between the tank and the carb and the previous owner said it wasn't smart to filter gas mixed with oil. (thought it was a dumb comment myself)

2) So, the line coming out of the crankcase doesn't need to be hooked to anything, like the tank? I guess these bikes don't have and don't need fuel pumps, right?

3) The previous owner also said to run 32:1. This seems a bit excessive oil mix. But, maybe for a 22 year old engine, thats not a bad idea? What is everyone else running?

[Manaen]

Originally Posted by stuff4mason

Thanks guys.

Two quick questions:

1) As I said above, the oil tank was removed. So, is it safe to run a fuel filter with oil mixed gas? There isn't a filter currently on between the tank and the carb and the previous owner said it wasn't smart to filter gas mixed with oil. (thought it was a dumb comment myself)

2) So, the line coming out of the crankcase doesn't need to be hooked to anything, like the tank? I guess these bikes don't have and don't need fuel pumps, right?

3) The previous owner also said to run 32:1. This seems a bit excessive oil mix. But, maybe for a 22 year old engine, thats not a bad idea? What is everyone else running?

1) yeah its fine although if you mix your oil and gas but make sure you set the mixture properly. The added oil will lean out your gas mixture

2) Nope but make sure you have it mounted at a high location to keep water out of the tranny.

3) too much oil.. the stock injection system will run from 50:1 to 75:1 at idle mix it at 50:1

[stuff4mason]

Well, heck. No wonder it won't start! Anyone want 6 gallons of 32:1 gas? I suppose I could just keep adding straight gas to it to thin it out.

Thanks for your info!

[LarryWannamaker]

Here is where the oil pump line connects to the pump... Line on the right - next to the rippled rubber boot!


And here is where it goes on my 87 - bottom of the oil tank... Not a great picture but it's the line on the left with the little green clamp.


As for the overflow lines they go through the holes up by the tank mount under the seat...

Hope this helps

[stuff4mason]

Yes, it does help. Oil tank was removed b4 I got it, so it explains all the open lines.

Thanks alot for your help!

[LarryWannamaker]

No problem... Let me know if you need anymore help!

[Manaen]

If the oil line was removed please make sure you plug the hole in the oil pump. With it open it could introduce additional air into the intake which will lean out your mixture. I would be a little concerned about running the engine with the oil pump disconnected and not removed. The oil flowing through the pump doesnt only oil the engine it also oils the gears in the pump. Without it being connected there is nothing to oil the upper section of the oil pump. If it locks up it could cause the metal gears to shred and fall into the engine. This could cause all sorts of bad things. So you have a few choices 1) you can continue to ride it and hope for the best, 2) you can re-connect the pump and not worry about mixing gas, 3) remove the pump pull out the gears and shims from inside the engine and then replace the pump.

If you want to continue to mix gas I would personally do number 3.