Jubilee runs rough under load

[Winch]

Tried my Jubilee for the first time using a box grader. Had the tines set deep to scratch up roots and rocks. Under load it ran rough. Pop, spit, misfire. I've only had it a little while and I drove it home about 3 miles on rural roads, 4th gear wide open. Ran fine that way. What do you think I should check first?

 

[Eman85]

70yo tractor, could be anything. Always good to start with a compression test, valve adjustment, check spark plug condition and points. Service all filters in the fuel system.

 

[old]

Tried my Jubilee for the first time using a box grader. Had the tines set deep to scratch up roots and rocks. Under load it ran rough. Pop, spit, misfire. I've only had it a little while and I drove it home about 3 miles on rural roads, 4th gear wide open. Ran fine that way. What do you think I should check first?

When it does that try to choke it a but. If it helps it is running to lean if it hurts it is running to rich so either way you need to adjust the main jet of the carb a bit.

 

[Winch]

I'll give that a try. I also think I'll go ahead and do a tune up. Any particular brand better or worse than others? How about this Sparex kit?

https://www.amazon.com/Tractor-Models-Jubilee-models-1964/dp/B01BX9EQCE

 

[old]

I'll give that a try. I also think I'll go ahead and do a tune up. Any particular brand better or worse than others? How about this Sparex kit?

https://www.amazon.com/Tractor-Models-Jubilee-models-1964/dp/B01BX9EQCE

If your going to do a tune up use NGK3112 spark plugs and standard or blue streak points. Napa or O'Reilly's has both

 

[Winch]

I'm having trouble finding those parts online. O'Reilly and Autozone won't let me search by tractor model, Napa does but I don't see the brand for the parts they show me. O'reilly does carry NGK3112. I guess I need to go into the store and talk with the sales rep.

 

[old]

I'm having trouble finding those parts online. O'Reilly and Autozone won't let me search by tractor model, Napa does but I don't see the brand for the parts they show me. O'reilly does carry NGK3112. I guess I need to go into the store and talk with the sales rep.

I buy all my tractor parts as for ignition from O'Reilly's but I go there in person

 

[old]

I'm having trouble finding those parts online. O'Reilly and Autozone won't let me search by tractor model, Napa does but I don't see the brand for the parts they show me. O'reilly does carry NGK3112. I guess I need to go into the store and talk with the sales rep.

I have a few different part numbers from O'Reilly's for the points depending on which distributor you have so you have to match them up to what you have. 25042, 25042X, AL5677XM, JP4D, JP43, JP45. One of those should be the point set you need

 

[Winch]

How do I tell which distributor I have? I'll take a pic after while and post it.

 

[old]

How do I tell which distributor I have? I'll take a pic after while and post it.

Best way is to pull the points out and take them to O'Reilly's so they can match them up for you

 

[Winch]

Makes sense. Thanks

 

[old]

Makes sense. Thanks

I've used that way of doing things to find part so many time I can't even count the times doing that worked out great and I got the part I needed

 

[Winch]

Of course you realize that methodology presumes the PO put the right points in for the distributor that's on there

 

[old]

Of course you realize that methodology presumes the PO put the right points in for the distributor that's on there

Yes but if the points where wrong it is not likely to have run correctly if at all

 

[Winch]

Started it back up today and it ran rough from the get go then died and wouldn't start. Appears to be out of gas! I had put a couple of gallons in it a few days ago and hadn't used it much at all and then I put about gallon more in today (all I had at the moment). Still won't start. I pulled the in-line filter just before the carb and no gas is coming out of gas line. Removed the sediment bowl and with valve wide open no gas there. How much gas has to be in the tank before it comes through the sediment bowl? I'll put 5 gallons in it in the morning. That's probably all the problem was.

I also checked the main jet on the carb. It was turned out about 3 full turns. I read somewhere to turn it all the way in and then out 1 3/4 turns. Does that sound right?

 

[Tim PloughNman Daley]

Tried my Jubilee for the first time using a box grader. Had the tines set deep to scratch up roots and rocks. Under load it ran rough. Pop, spit, misfire. I've only had it a little while and I drove it home about 3 miles on rural roads, 4th gear wide open. Ran fine that way. What do you think I should check first?

Is system OEM 6V/POS GRN or a 12V Switch Out Job? Firing order/wiring right? 1,2.4.3 CW. Check plug wires for loose connections. Carb back firing could be a fuel issue but also an electrical short somewhere can cause BF'g too. If carb passes the Fuel Flow Test, leave it alone. Using a correct wiring diagram, verify entire wiring is correct. Often guys wire their lights wrong, especially if using 12V, and can be a root cause. FACT 99.98% of all non-starting/non-running/rough running issues are due to incorrect wiring regardless if 6V or 12V. Troubleshoot. Don't guess. Avoid replacing with new parts willy-nilly. Use your ESSENTIAL MANUALS and the wiring PICTOGRAM.

Tim Daley (MI)

 

[Winch]

It's been converted to 12V. I don't think it's electrical. Just not enough gas in it. I'll find out in a little while when I gas it up. Thanks for the pictogram. Is that in the FO-19 service manual? I bought an original hardcopy that's supposed to be here today. The online version that is a copy of a copy of... is near worthless.

 

[pomester]

Started it back up today and it ran rough from the get go then died and wouldn't start. Appears to be out of gas! I had put a couple of gallons in it a few days ago and hadn't used it much at all and then I put about gallon more in today (all I had at the moment). Still won't start. I pulled the in-line filter just before the carb and no gas is coming out of gas line. Removed the sediment bowl and with valve wide open no gas there. How much gas has to be in the tank before it comes through the sediment bowl? I'll put 5 gallons in it in the morning. That's probably all the problem was.

I also checked the main jet on the carb. It was turned out about 3 full turns. I read somewhere to turn it all the way in and then out 1 3/4 turns. Does that sound right?

Fuel is one of the necessities for ICE performance. The system should drain the tank dry before losing fuel at the carburetor. Likely scale in the tank clogging the sediment bowl inlet. I'd replace the sediment bowl, open the valve, remove the gas cap, and blow 10psi or so of compressed air back up the fuel line - likely that will displace the debris. Have a gas can and a bit of hose to drain the tank. Once empty you can evaluate how bad it is. Maybe you can remove the sediment bowl assembly and flush the tank, maybe you'll want to remove the tank to do a better job. Radiator shops are often set up to clean tanks.

Three turns out at the carburetor is a lot. Basically wide open orifice. Probably in response to fuel starvation. I wouldn't worry about that until there is good fuel flow thru the system.

 

[Dean]

Tried my Jubilee for the first time using a box grader. Had the tines set deep to scratch up roots and rocks. Under load it ran rough. Pop, spit, misfire. I've only had it a little while and I drove it home about 3 miles on rural roads, 4th gear wide open. Ran fine that way. What do you think I should check first?

Misfire is usually (no, I did not say always) caused by ignition problems. Verify that all ignition wires are fully inserted into the distributor cap and inspect wires with engine running after dark for evidence of sparking. Replace wires if you find such evidence.

Of course, you have already verified that spark plugs are clean, properly gaped, the cap and rotor are clean, undamaged, that there is no evidence of carbon tracking, and that points are clean, properly gaped and not pitted....

 

[Winch]

Put 5 gals of gas in it and cleaned the sediment bowl and replaced the in-line fuel filter. Starts good, runs smooth for about 20 seconds then starts to miss and continues on getting worse until it about dies. Every once in a while when it's missing bad it returns to running smooth but only for a few seconds then goes back to missing again.

Can I attach a video file? First I have to figure out how to get it on this computer from my phone. Just sharing it says it's too big.