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Discussion Starter #1
Well I can't seem to figure it out. New plug wires, plugs, cap, points, condenser and I brought down one of my rotors. I tried timing it and retiming it, cleaned the carb up and put it back together. Reset it to factory setting (1.5 turns out) and put it back together, and nothing I did made it run better than before. Anybody have any ideas?

At the start of the video it is timed per the allis service manual. I adjusted it during the video to fine tune it and it ran a lot better, but the going from running smooth to rough and backfiring has me puzzled.

http://www.youtube.com/watch?v=goPwzEr-H1k
 

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Videos are difficult for me because I only have dial-up internet service, but should valve adjustment be checked? Assuming all electrical functions are correct, I would take the drain plug out of the carb and make sure you have a good fuel flow. Just a couple of thoughts.
 

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Well, once I put on my night vision goggles I could see a whole lot better.... Are you sure ALL the plug wires are on in the correct sequence ? Sounds like its really laboring to run.... It may be able to run on two at wide open throttle and backfire the unburnt fuel and die when you go to midrange ?? I'd still check firing order first.
 

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I had a very similar problem with my 175 this Summer. Started running like that and I gave it a standard tuneup.
New points, plugs, condenser etc. Ran good for a couple of hours, started again. Pulled my hair out for about a week,
rebuilt the carb, adjusted and readjusted the timing, replaced everything from the Distributor back to the battery.
Nothing helped. It would idle good sometimes, but above 800 rpm it sounded like yours. Thought maybe the advance in the distributor was worn out. Maybe?
Finally went back to my local tractor mechanic for help questions.
After a bit of yes and no questions, he said they had found several bad condensers from their supplier (Tisco) returned by their customers.
Go to NAPA and get a good one. I did that, and it has ran like a stripped snake ever since. Never thought of the condenser being bad out of the box.
Might be one place to look. Also make sure the wire from the coil to the points, isn't grounded where it goes through the distributor.
All electric connections clean and tight. No wiring grounded.
 

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firing order is 1 2 4 3
Id go with big dave on the condensor.
To set the carb once its running, goto full throttle and screw the main ajuster in till it starts to die. then back out about half a turn ;)
 

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Discussion Starter #6
I apologize for the night video. That was just the time we had to work on it. Plug wires are in the same order as mine are. I checked and double checked, then checked when I got home. The fact that I replaced the points and condensor, and it didn't run any better, I'm not sure. I guess I can't rule out another bad condenser, but you would think that it would run a little different with a different bad condenser. It acts the same whether it runs ten minutes or an hour. I almost need to get it up here to my place so I can trouble shoot it easier and have quick access to answer questions. Two hours is a long way to try to keep travelling.
 

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you may wish to try another coil -
you may wish to try another fuel supply, like a 1/2 or gallon tank with fresh fuel plumbed direct, just to eliminate fuel quality/supply
has the bushings in the distibutor been check for excessive wear - if the shaft wanders dwell will be erratic
 

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Discussion Starter #8
I had him check the play in the distributor and the springiness of the advance weights, to which he replied "oh, the rotor is supposed to spring back? When I put pressure on it either way it just goes there and stays" So I'm guessing the distributor is just shot and needs to be rebuilt. I didn't check the bushings and 2 hours away from me is a severe disadvantage right now
 

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hopefully the dist is just gummed up and can be made useful with some cleaning and lubing
working on something away from home always adds to the hassle - but looks like you may be heading in the good direction
 
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