1952 8N carb

[RevJohn]

Hello folks! I have a ‘52 8N,12 volt conversion. I have a new carb,checked the float,needle and seat but trying to start it,it floods. Gas comes out the air intake. So naturally it will not start. It will sputter at times but that’s it. My original carb cracked,that’s why I got a new one but it did the same thing. One day started,run a few seconds and that was it. It’s not ran in 2 weeks. Any ideas?
Thanks a lot!
RevJohn

 

[Royse]

When you try to start your tractor and use the choke, gas is pulled
up into the manifold. When you stop cranking the engine, it runs
back down into the carb and runs out the air intake.
That's actually quite normal and may indicate you are holding the
choke out for too long while trying to start the tractor.

Since both carbs did the same thing, I would check spark quality.
Use an adjustable gap spark tester and make sure the spark will
jump a 1/4 gap at all four plug wires. If you don't have a spark
tester, use an old plug widened out for now. The tester is about $8.

 

[RevJohn]

Hi Royse. I have spark at the plugs,very good at that. I did not realize that gas ran back down...you taught me something today. Lol!
I checked to make sure it was “in time”. Number one piston tdc and the rotor is at number one plug on distributor cap.Any other ideas are welcome.
RevJohn

 

[Royse]

Is this a new tractor to you or one that just quit running?
Firing order 1-2-4-3 Counter clockwise after you verified number 1.
Now that the plugs have been flooded, I would clean them with a
propane torch or replace them with a spare/new set for testing.

 

[Dell (WA)]

Rev John.......keep yer itchy-twitchy fingers off'n that handy-dandy spring loaded choke knobie. Heres the drill.....ignition ON, tranny in NEUTRAL, press the BIG THUMB switch by the tranny shifter, after 2-rumpas, QUICKLY pull the spring loaded choke knob. You only need to feather the choke iff'n its real cold, like freezing. Shuld run without choke after about 5-mins. ...2nd advice... learn to adjust yer M/S carbie. Even brandy new carbs need to be adjusted. Set the down-pointing MAINJET to 2-turns and LEAVITT!!! Adjust the side-pointing IDLEMIX fer FASTEST idle NOT SMOOTHEST idle. Understand the difference??? Shuld be about 1/8-1/4 turn. Remember the idlemix is BASS-ACKWARDS, out fer lean, IN fer ENRICH. After you gottchur carbie idlemix adjusted, adjust the BEHIND the carbie idle speed fer enny thang under 500-rpms. Don't haffa "proofmeter", buy an el-cheapo rice-rodder tach and run it on 9-volt battery. I once got my eazy starting 6-volt 51 8N to idle at 375-rpms with an external tacho. ...3rd advice... gittcha some hollow ground gunsmithing screw drivers which won't waller out yer soft brass jets like common "V" bladed screwdrivers ...4th advice... iff'n yer still haffing carbie jet removal problems, BOIL yer cast iron carbie in HOT WATER. (really) The tempature will expand the cast iron and yer brass jets will be eazily removed. Simple, eh?.......Dell, yer self-appointed carbie-meister

 

[Tim PloughNman Daley]

Model year isn't important, front mount or side mount is as well as 6 volt and 12 volt. You've stated it is a 12 volt '52 so we assume it is a side mount and that is what's important. How does a carb get cracked? I'd like to see it -can you post pictures or send me some -email is open. If new one is doing the same as the old one, wouldn't that tell you it isn't the carb? Is the 'new' carb a Marvel-Schebler or a Zenith? Before you installed the 'new' carb did you go thru it and check float level and set the idles to correct initial starting points or was it slapped onto the tractor out of the box? Never trust anything new out of the box. These old N's parts were designed to be rebuilt over and over. Most of todays parts come from Cheena -the land where Quality Control means nothing. Pull plugs out and dry off with a quick burn using an electric candle lighter and bars brush off the carbon deposits. With Sediment Bulb valve CLOSED, loosen the carb drain plug on the bottom and if there is fuel dripping out, your carb isn't set up right. Only when valve is open should fuel flow thru the drain.

Tim Daley(MI)

 

[RevJohn]

(quoted from post at 06:50:30 11/28/17) Model year isn't important, front mount or side mount is as well as 6 volt and 12 volt. You've stated it is a 12 volt '52 so we assume it is a side mount and that is what's important. How does a carb get cracked? I'd like to see it -can you post pictures or send me some -email is open. If new one is doing the same as the old one, wouldn't that tell you it isn't the carb? Is the 'new' carb a Marvel-Schebler or a Zenith? Before you installed the 'new' carb did you go thru it and check float level and set the idles to correct initial starting points or was it slapped onto the tractor out of the box? Never trust anything new out of the box. These old N's parts were designed to be rebuilt over and over. Most of todays parts come from Cheena -the land where Quality Control means nothing. Pull plugs out and dry off with a quick burn using an electric candle lighter and bars brush off the carbon deposits. With Sediment Bulb valve CLOSED, loosen the carb drain plug on the bottom and if there is fuel dripping out, your carb isn't set up right. Only when valve is open should fuel flow thru the drain.

Tim Daley(MI)

Tim it was cracked by a friend that I had work on it while I was out of town. Yeah he means well...that’s all I will say.Lol! Long story but had nothing to do with my problem.
It is side mount. I went through it when I got it. I adjusted it as Dell had said. It has EI but it checks fine.
Thanks for the help. I’ll let you know what I find out.
RevJohn