Jubilee Runs Rough

[TheJubileeGuy]

Hey guys, need some help here. I’ve got a ‘53 Jubilee that I’m going through right now, it has a new fuel tank, new fuel line, new sediment bowl. Tractor has been converted to 12 Volt and to electronic ignition, so no points.

My issue - The tractor runs like crap with the choke off. I dissembled the carb, cleaned it really well, put it back together, tractor runs the same. If you pull the choke out about 1/3 of the way, the thing runs PERFECT. Runs really well. I have ordered a new exhaust manifold and gaskets because I can hear it ticking and I know it’s leaking, so maybe that could have something to do with it?

Also, something I was wondering, Like I said it has a OEM metal new fuel line. When the line leaves the sediment bowl, it has a slight back grade in it TOWARDS the sediment bowl. I was going to put a bend in it and get it slipped towards the carb but figured I would ask if that was supposed to be that way for some reason? It’s a pre bent fuel line. Ordered from this website.

Thanks for any help in advance. If I can get her running with no choke the way it runs with slight choke I will be very happy lol.

 

[John in Mich]

Try cleaning the plugs or replacing them. Fouled plugs are a weak spark. Weak spark requires more fuel.

 

[Tim PloughNman Daley]

How did it run before you changes al those parts? I'd fix the root cause first before buying and installing any more new parts -"...I have ordered a new exhaust manifold and gaskets because I can hear it ticking and I know it’s leaking, so maybe that could have something to do with it?" More guessing and have not performed any root cause problem solving. Does carb pass the fuel flow test? If so leave it alone. I'd be looking into the electrical system. Got spark? 92-1/2% of all non-starting issues are due to mucked up wiring and most are from incorrect 12V switch over jobs. There are but a few correct ways to wire a 12V system and a thousand incorrect ways. Many fellas don't understand the FORD 6V/POS GRN electrical setup, have starting issues, so assume a 12V will fix it and then throw in EI and yet still have non-starting issues. Work with the ESSENTIAL MANUALS --- don't have them? That's a shame. JMOR has his wiring PICTIGRAMS - go the other Ford N-SERIES Tractor site to get a dwonload copy.

FORD OEM NAA TRACTOR OWNER MANUAL:

CLYMER/I&T FO-19 SHOP REPAIR MANUAL – FORD NAA ’53-’54:

FORD TRACTOR 1939-1953 MPC:

FORD TRACTOR 1953-1959 MASTER PARTS CATALOG:

FORD TRACTOR 6V/POS GRN WIRING, ANGLE MOUNT DISTRIBUTORS:

ANGLE MOUNT DISTRIBUTORS, 12V SETUP:

Tim *PloughNman* Daley(MI)

 

[TheJubileeGuy]

Thanks for the responses.

The tractor is a family heirloom so to speak, my Great Grandfather bought it new, my grandad had it, now I have it. It was restored originally about 25 years ago and I assume the 12V conversion was done at that time. The tractor has been 12V the entire time I’ve known it.

To answer the question of how did it run before all that, it ran fine. The tractor has been sitting for about 3 years, because I just don’t have much use for it, however I cannot part with it. I got tired of it sitting and have decided to do some gardening with it just to give me a reason to run it. The clutch was frozen, and the fuel tank had begun to leak at the front bracket (I’m told is common). So I have put a clutch in it, and replaced the tank, sediment bowl, and fuel line for the reason stated above. While I was doing that, I went ahead and changed it to electronic ignition because I hate and have always hated, messing with points.

The tractor does run, just runs rough with choke all the way off as I said. With the choke pulled out about 1/3 of the way, the tractor runs really, really good.

I will check the coil, and could you explain how I can check flow to the carb as you mentioned? Also, any opinion on the slope of the fuel line leaving the sediment bowl? It’s a pre bent replacement and it slopes back towards the bowl, not the carb in its first section. Should I bend it downward towards the carb or is it supposed to be that way?

Thanks, I’ll also look into those manuals

 

[Jim L WA]

You can check the fuel flow by removing the plug at the bottom of the carburetor, and see if you an fill a pint jar in a two to three minutes. I didn't see where you tried adjusting the main jet screw. Have you?

 

[Tiger Joe]

running with choke partially out means you either have too much air or not enough fuel.

with the way modern gas causes havoc in carbs sitting, I would tend to lean toward a carb issue.

you said cleaned carb well, did you completely disassemble and clean all jets and passages? im thinking crap gas clogged it

 

[TheJubileeGuy]

Completely disassembled it and cleaned everything. It was dirty for
sure. Did not make the tractor run any differently though. Same
issue. I will test the flow this evening.

 

[TheJubileeGuy]

I will test the flow of fuel. I have not messed with the main jet screw. May end up adjusting it again

 

[Jim L WA]

If it passes the flow test, then don't worry about the fuel line routing. Try turning the main jet screw out 1/8 turn at a time after it warms up. Let us know how it went.

 

[TheJubileeGuy]

Alright guys, here’s all I was able to do tonight.

-Shot some carb cleaner at the gaskets and around the manifold and was not able to change the idle. So it shouldn’t be a vacuum issue.

-Ran it with the gas cap off to see if my cap was faulty. No change.

-Did a flow test. It filled a 16OZ cup in 2 mins and 14 seconds. I assume this is adequate?

-Adjusted both needles again. Set idle at 1 turn then set main at 1.5. No change. Set main at 2 turns and it MIGHT have ran a little better?

I plan to test spark tomorrow evening.

Good thing is it still runs awesome with a little choke lol

 

[RoadsideGeo]

So here's a real shot in the dark...

Pull the air cleaner hose off of the carb and check the choke butterfly position in respect to the pull knob.

Perhaps somehow it is positioned incorrectly.

 

[TheJubileeGuy]

Tested the spark tonight. Nice blue spark. So, the issue isn’t in the ignition. I’m about at a loss.

 

[Jo Bird]

Have you tried running it with the air pipe disconnected from the carb ? Try that and see if it helps.