Hesitation problem

[duke7595]

Coyote machine,

Here are some of the pictures of the tractor, the carb. manufacturer is Scribner.
This is what I have done since the last post. 1. Drained carb.(no water, fuel clean) 2. installed in line filter on opposite side of carb. just before the the
fuel pump (pic. did not come out, ) 3. Drained and cleaned fuel tank ( looks good) 4. Breather cup was cleaned and filled w/ new oil (not to dirty, but old )

I started the tractor with the breather hose off and it had some powerful suction, more so than any I have encountered in the past on other tractors, I don't know if this is good or bad, anyway I did squirt a few shots of carb. cleaner into the carb.

I believe the tractor is running better, however, I'm going to replace the plugs again since they have become sooty. With the new plugs I will be sure
I have covered all bases.

I noticed that the fuel pump is very similar to a diesel except it lacks the lift arm. I also added some pictures of the tractor in it's tear down process,
you may have noticed where I had to cut the old steering wheel off , first time I had to do that.
It's a shame this is not a diesel as it came from the factory with dual remotes which was a definite option back then as well as P/S ..

The tractor was stored inside a garage in Iowa for approx. 4 years, the gas had been drained before storage, this may have something to do with
it's problem, also we changed all the fluids and filters before we ran it for any length of time.

Well sir if the plugs take care of the problem I can continue tearing down the rest of the tractor and make it look new again. I'll show you the end result when finished.

The tractor is a 1971 with 3341 hours on a working tach, I'm not sure what type of gas was used.

.

 

[duke7595]

 

[duke7595]

jd110,

Thanks for the tip on the plugs, it has Champion in it now but will change to AC tomorrow, No I have not adjusted the carb. however, I will now that you
have pointed that out, Thanks for the input.

 

[duke7595]

OK! Now I have a better idea what you're dealing with:confused2:
For the moment forget about adding a fuel filter in line to the carb. I'd break out a can or two of PB Blaster or whatever you use to loosen up stuck/rusted stuff and hit every bolt and clamp near the carb and especially where the carb attaches to the intake manifold. Then at the end of the intake tube feeding the carb go to the bottom of where it says inspect daily or once per century, and undo the clamp and carefully take the oil bath pan and dump its contents into your neighbor's stream, so it flows toward his house:shocked: Just kidding- dump it into a container of waste oil to get rid of later on.
Then see if in fact there is an element of some sort in the big canister above the label I spoke of earlier. I'd go to your favorite JD dealer's web site and with your model, serial number and such search for a kit to rebuild your carb. And get an intake manifold gasket too in case you need to replace the one you have already on there.
The rubber hose between the carb and air cleaner tube will also likely need replacing, but not necessarily. You want to find parts available BEFORE you take the carb apart to clean it. All the brown gunk on the outside of the carb is varnish from gas leaking, and dirt too.
I noticed a solenoid looking thingy stuck into the carb near the back, with a wire barely attached to it. You should be careful not to break the connection to that sensor. I'm not sure of it's function yet but I can say it is most likely crucial to the carb running properly.

I need to know what year this tractor was made, and whether it ran on leaded or un-leaded, how many hours on the clock, etc.
Gimme some history!:confused3: Please.
Do you have a service manual or anything like that?
Can you tell me where the wire on the sensor runs?
Good pics. Let's have some more of the wiring, fuse block?, anything that might proove useful.
What's the jumping deer insignia on the front grille for?

Yes sir, I can take some pictures of the wiring from the solenoid to it's end and the fuse block as well.
The jumping Deere was a standard for all the John Deere's of that era, it unbolts from behind the grill, thankfully this one is undamaged as John Deer are very
proud of these, dollar wise.
You notice that this Deere has 4 legs, some earlier models have 3 legged Deere insignia's . Just a little trivia.

 

[Coyote machine]

Glad to hear it is running better, BUT the fact it was designed to run on leaded gas means that has a definite effect on what you need to run in it for gas now. Leaded obviously coated the valves back in the day and it was part of the inherent design of the way tractors were built then. Now without the lead the valves don't get the coating as they were designed to do, so with the amount of hours on the engine, (and I'm assuming for a moment there was never a rebuild done on this engine), or if one was done it might have been just a head cleaning and reseating of the valves. So the valve train doesn't necessarily need any more lead in it's life BUT it does need a higher octane than current UN-leaded gas provides; so I would venture to guess that the best way to get good performance out of this engine would be to use the highest octane un-leaded you can afford.
Lots of intake tube suction to the carb is never a bad thing, often it is what is lacking and causes run problems. Because of good suction and for other reasons i don't dislike using carb cleaner BUT it does tend to dry things out so following it with some WD-40 or similar might not be a bad idea.
When you say soot is on the plugs let's see pics of the plugs for diagnosis.
And see what you can do to get a pic or tow of the new inline fuel filter. Write on it date and hours on clock.
Is the restoration going to be a for use or for show job?
BTW, I'd want to run a compression test on the engine to get a 'before' reading. Just something basic, turn it over a few times, ground the hi tension wire of the coil to a good metal ground when cranking, and shut off fuel if possible...
Show results.

 

[murphy1244]

If your going to keep this tractor you need to do a valve job. The conversion for unleaded gas on earlier motors is Stainless steel exhaust valves with stellite? seats. Run some SEa Foam in it too.

 

[Coyote machine]

If your going to keep this tractor you need to do a valve job. The conversion for unleaded gas on earlier motors is Stainless steel exhaust valves with stellite? seats. Run some SEa Foam in it too.

So Murph, what is the result of not converting the old exhaust valves and seats? I suspect some run these old motors without converting over, either because of the expense, or lack of knowledge of the problem.

 

[Tx Jim]

Solenoid on bottom of carb is supposed to be an anti-dieseling device. Float is metal but can develop a hole in it to hold gasoline. Be sure and check parts key #18(strainer) for trash. It's unusual to see a utility tractor that age with dual scv's(rear remotes).

Drawbar (claimed): 33 hp [24.6 kW]
PTO (claimed): 38.82 hp [28.9 kW]
Drawbar (tested): 31.81 hp [23.7 kW]
PTO (tested): 38.92 hp [29.0 kW]

 

[jd110]

I agree with using higher octane gasoline. Especially with the addition of ethanol at 10%(at least in this area) the tendency to vapor lock is greater with 87 octane than 91 or 93 if available. The anti-dieseling solenoid is supplied 12 volts directly from the ignition switch. The solenoid shuts off the flow of fuel to the main jet in carburetor.

 

[duke7595]

Just Got home, Thanks Tx. Jim , jd110 and coyote machine for all your help, I am gone to continue work on it in
a day or 2 . Will let you know how it go's..