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Discussion Starter #1
Help!!!

The 77 panther 340 started and ran just fine this morning. I removed the Walbro carb, took it apart and cleaned it. Installed it. Now I can't start it.

Here are the vitals...

- Spark on both cylinders
- 140 psi compression both cylinders
- Major flooding of the engine to the point that it will not turn over.
- Good vacuum

When the fuel line is removed from the carb and just a shot of carb cleaner or starting fluid is shot into the carb it still will not fire. I grounded the plugs to the block and turned over the engine and have good blue spark... I let the cylinders dry out... still no start. Screwed the idle screw in all the way, and the main screw in all the way... back each out 1 turn on each try... nothing.

I am very confused about this... IT HAS EVERYTHING IT NEEDS TO RUN!!!! What am I missing?!?!?!?!?!
 

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possible that when u put the carbs back together that the floats got stuck and or the needle isnt sealing the passage off when the bowl is full of full hence it will flood the crap outta the sled.
try taking the carb apart again and make sure everything is as it was before as far as making contact between the floats and the metal plate that pushes on the needle
 

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Discussion Starter #3
Took it apart 4 times... It's not flooding any more. But it did backfire and the compression is now 60psi on one stroke... I can get it to 150 psi after 3 - 4 strokes.

THoughts?
 

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To do a proper compression test you need both plugs out, hold the throttle wide open and pull multiple times till the guage stops moving.
 

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Discussion Starter #6
This is my plan for today...

- checking that there is no air leak between carb and block
- disassemble, clean, reinstall carb
- dry out engine from flooding by removing plugs and fuel line and then cranking a few times
-check compression again after reinstalling carb but before atempting to start


If compression is good (100 - 160psi) the head gasket shouldn't have a problem should it? Thats the only other problem it could be...

I really am boggled by why I can't even get fire when I use staring fluid. Like I said in previous posts, when grounding the plugs to the block I have spark. I am using the electric start to crank the motor... Are there any wires I should check? I don't know If I would start down the path of electrical because I am getting spark.

Thoughts?
 

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When you lay the plugs on the heads, you are twisting the end caps some and when the plugs are in the head, the caps are twisted the other way.
This is where you are losing spark.
Unscrew the plug caps from the end of the wires and clip off 1/4". Screw the caps back on until tight and you should then have good spark.
 

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Discussion Starter #8
Problem Solved? (this is a 1974 not 77 btw)

Well just got in from the shop... Success, Maybe.

Took the plugs out and dried out all of the fuel from the block and crank case. There was a lot left in from yesterday. Took the carb off and cleaned again... and then reassembled and installed. Cranked and got a little sputter... gave it a shot fuel in the carb and it ran for a few seconds. Pulled the fuel line off the carb and had some fuel being pulled to the fuel pump but not into the bowl. I have air leaks in the pump I think. The gaskets were pretty worn out. So I ordered a new rebuild kit. We'll see if that helps... I should have it back together by Thursday night. But it's defiantly a fuel / air / carb issue.

Thoughts?
 
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