Pre-mix ratio....

S

sommerfliesby

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I picked up a 78 Exciter 440 for fun last fall, and when I brought it back to my shop, it promptly left a puddle of oil all over my floor. Either the tank itself or a line is split, and I'm not about to tear into it to find out as I don't have the time or inclination. I figure the easiest way around this problem is just to run premix (this is not going to be a trail sled...just a field runner for my neice and nephew to play on).

Can somebody tell me what ratio to run so I'm not changing plugs every second?

Thanks!
mike
 

FIX IT, REPLACE THE TANK! Listen to Tony! All new sleds run oil injection for good reasons!
 
probably just a loose or cracked supply line..should be easy to find and fix on that sled..I use to own a 78 exciter 440.They are a real good sled to ride.
 
Check the lines but if the tank is cracked just call up a sled salvage yard and they should have one no problem. If that's what it is, and I have seen cracked tank on a Phazer ONCE. It shouldn't be difficult to change. If you are not familiar with all the benefits of oil injection, I suggest you look them up before using pre-mix.
 
See...that's why I came on here ASKING. I am aware of the benefits of oil injection...I am also aware of people REMOVING oil injection and premixing.

As for the "who's to say gas won't be on the ground too"...well...the gas tank IS NOT LEAKING....so I guess I'm the one to say that.

This sled is by no means a QUEEN...I picked it up for $400...I just want to run it maybe once per season for the kids. I've got three other sleds to run and maintain, my big reason for not wanting to tear into this is time. But, if there's no other way, I guess I'll have to.
 
Sooooo....still no answer then....because, technically, if the oil and the gas are PRE-mixed, the oil WOULD in fact be in the engine...correct?
 
Simple question here guys....I think he understands well enough that fixing the problem would be the best scenario, so stop pounding it in to him.

If someone has an idea on what would be the best premix ratio to run, please help him out by posting, if not, dont reply.
 
Sno-Xr said:
Simple question here guys....I think he understands well enough that fixing the problem would be the best scenario, so stop pounding it in to him.

If someone has an idea on what would be the best premix ratio to run, please help him out by posting, if not, dont reply.
Click to expand...

Finally, a sensible answer. If I knew the ratio I'd gladly give it to ya. Personally I would start rich, plugs are cheap, and being for kids you dont need every ounce of grunt. 32:1 is where I would start, seems alot of older 2 strokes like that ratio.
 
ex 440 with good oil 40:1 mix or 16oz to 5 gallons that is the way we run all of our races sleds that have had the oil injection deleted .........but i would rather have the oil injection i still run it on my gpx's and ex 440's that i trail ride and never had a problem like was said hard cracked line or one of the nipples broke off on the bottom of the bottle also take the the seat and tank cover off and where the hols down pipe runs across the top they like to crack there due to tightening the hole down too tight that is why there are locking tabs for the bolts just snug the bolts and bend up the locking tab to hold the bolt from backing out
 
no bashing here..but was thinking..if line is cracked,or nipple broke..if the oil pump keeps turning but draws in air instead of oil..will that not cause a lean condition which could be fatal for the motor..just wandering...
 
bluemonster1 said:
no bashing here..but was thinking..if line is cracked,or nipple broke..if the oil pump keeps turning but draws in air instead of oil..will that not cause a lean condition which could be fatal for the motor..just wandering...
Click to expand...

X2 ;)!
 
I think what BM was refering to is if the normal injection system injects the oil after the carburator, premixing would cause a lean condition. This would be caused by oil taking up some of the volume of fuel that is fed through the carb, hence less fuel to air =lean
I dont know how the injection system is set up on these sleds, maybe someone could help with more info
 
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Sno-Xr said:
I think what BM was refering to is if the normal injection system injects the oil after the carburator, premixing would cause a lean condition. This would be caused by oil taking up some of the volume of fuel that is fed through the carb, hence less fuel to air =lean
I dont know how the injection system is set up on these sleds, maybe someone could help with more info
Click to expand...

I thought he was meaning that even if you premix and run it that way that where it is leaking would suck air and put it into the line creating a lean condition. I have run nitro r/c cars and this is something that can happen with them even a bad seal in the motor will cause it. I have blown a r/c motor this way. The seal on the back plate failed and it sucked air and ran lean and blew the motor.
 
smitymike11 said:
I thought he was meaning that even if you premix and run it that way that where it is leaking would suck air and put it into the line creating a lean condition. I have run nitro r/c cars and this is something that can happen with them even a bad seal in the motor will cause it. I have blown a r/c motor this way. The seal on the back plate failed and it sucked air and ran lean and blew the motor.
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Oops, your right! :o| Thats what happens when I post from my phone.. lol

What I described is another thing to consider when thinking about premixing ;)!
 
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