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Discussion Starter #1
I got a 93 Mach 1 670 and for the life of me or at least the life of my arm, that sucker won't start this season. It sat last season & trying to get it going to trade her in. Seems like lots of spark but plugs are wet & motor justs floods.. Went through the carbs & nothing seems stuck or plugged. Wondering about any suggestions.

Good early season workout for the arm, but this is getting ridiculous.

I guess it maybe just doesn't want to part w/me
 

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I've got my money on bad fuel.
You should yank the 40's off, dissassemble and clean them up. If the fuel is bad it has likely gummed up the carbs.
Siphon out the tank and both pumps completely, fuel it with fresh gas and she will likely fire right up.


Have a great day!

Scott
 

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Discussion Starter #3
Tried the fuel thing & still wearing the heck out of the old arm>
Fuel in bowls seemed clean & everything in working order as floats or such. But flooding even harder w/fuel in the exhaust.
Wondering what else I could check. Spark seems goods, got new rings no more than 400Miles ago.
Maybe it's time she meets the "ether bunny". Don't know is this is advised but would like to at least here a bark out of her>>>

The soon to be "Pull-start King"
 

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If its flooding, its got to be something in the carbs. is extra fuel getting in the primer line somehow?
 

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That gas is comming from somewhere, and if your saying the floats are good, then I'll bet your crankcase is flooded due to a hole in one of the fuel pump diaphrams.
This can cause your crank to flood (ie fill up...a lot) with gas. Pull off the impulse line at the bottom of the motor (the hose that goes to the fuel pump) and see if gas pours out. Be carfule. If your crank IS flooded enough, this can cause the dreaded "hydro-lock" and bend/break a rod when you pull the cord.
The diaphram kit cost a few bucks and a re-build can't hurt anyway.
One last thing. Make sure your pipe is clear (no mouse nest or critters).

Trapper
 

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I had a simular problem on a 500. Turned out the cut-off-switch was not opening and contacts inside were stuck.
I used contact cleaner but no help, had to pull the thing apart to fix it. Use a continuity tester or just jumper the wires and try it...good luck :)
 

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Discussion Starter #7
Never thought about fuel sneaking in from the fuel pumps, but that's probably the culprit. I haven't had a chance to check it out yet but I do have two questions about it.
Do you check the pump just by fuel in the vacum line or is there something else???
Also if there is fuel in the crank, which I'm sure there is as when I checked my pipes it had fuel in it;
How do you get it out??? With this new power developing in my pull-start arm, that hydro lock sounds like a bad thing!! Do you just leave it to good old evaporation...

The pull start king
 

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Turn off the gas and the igniiton.Then pull out the plugs and pull the engine over hard .If the crankcase is full you'll see the gas fly right out of the plug holes.It will eventually turn to a vapour and then to nothing.Put dry plugs in and try it (leave the gas off).It will likely start and then die.Pull the plugs again (they'll probably be soaked) and pull it over a few times again.Dry plugs and try it again.You may have to go through this routine a few times to get her dried out.Once it runs and then quits and the plugs are dry your ready to try turning the fuel on once you've figired out why it was flooding.Don't you wish you had electric start right now :cussing:
 

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Dear Pull Start King (sorry, I couldn't resist)

There shouldn't be any fuel in that impulse line. All that does is pump the diaphram in the fuel pump via the presure change in your crankcase (caused by the piston doing it's thing).
Personaly, I would pull the pump and do a rebuild. It's easy to get to and will only run you about $7.95 and 15 minutes of your time.
To remove the fuel from your crank, you only need to remove the spark plugs from your engine and put that super strong arm back to work (MAKE SURE YOU HAVE THE KILL SW. IN THE OFF POSISTION or your life may become even more exciting than it already is). A rag thrown over the plug holes will keep your garage ceiling clean. You can also get alot out via that impulse line mentioned eariler, but beware, it's most likly hard and britle and will need to be replaced if you fool with it. If your pipe is really full, it's best to remove it and dump the stuff. The gas can block the pipe and cause a no-start. A 2-cycle engine doesn't have valves like a car and is not able to blow the fuel out. If the out-going passage is blocked (in this case the pipe) the intake will not suck fresh air in.

Good luck,
Trapper
 
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