Farmall 706 LP tractor wont start

This message is a reply to an archived post by martin simmons on April 05, 2008 at 07:56:51.
The original subject was " Farmall 706 LP tractor".

hey guys has been awhile but iam back. you are probably wondering what happened to me well i got into a wreck awhile back so the tractor went on the back burner. but now iam all better and ready to fix my tractor. there has been no new progress on the tractor since i last left you. but to day i went out and got back to where i was last time. i drained the oil of water on the front was about half a gallon in there and replaced battery cables with new one. that is all i got done before it started to rain on me but i have a few questions for you guys. 1 what socket does it take to get the spark plugs out. 2 what lube should i put on the rear diff drain bolt to free it up. cause mine is stuck bad unless i was turning it the wrong way. i tried wd40, chain sawlube,and white litheum and you do twist it to the left or is it a left tightening right loosening bolt. and what size socket fits that bolt. i had my small truck toolbox with me and could not find one to fit it. 3 could someone post a picture of where the choke cable connects cause as you all know i dont know much about this tractor. 4 where do i put ether in the spark plug holes or the tank i rember someone saying it helps tractors that have been sitting for awhile start. cause i know it is very volatile and helps the starting process but i dont know where to put it. but i have seen my trucker friends use it to change tires. 5 what is the proper gap for the spark plugs i want to say 0.20 but just want to make sure. 6 where"s the starter button on this tractor i know i have probably looked over it 20 times but cant find. 7 what is the little button in the middle of the propane regulator for i want to think it it to let pressure or moisture out. sorry about all the questions guys i just really wont to get it running and use it. if all works out i hope to have it running in a few days to a week cause it did not feel locked up but i will double check tomorrow to make sure and thanks guys for all the help.

come on guys just need a little help here. oh you can drop the either question i figured it out

Never use either to start a propane tractor, You will blow the head clean off of it. The button in the middle of the vaporizer, [not regulator] is a propane primer button, you push it in for 2 or 3 seconds to allow propane to be injected in to the manifold for easier starting especially in cold weather. If I had to guess, you must have an Impaco vaporizer model E if it has this button. This is not a factory vaporizer, the originals were made by Ensign and no longer available.
As far as the choke cable goes, Is this carb an Ensign carb? If you have a vaporizer that has a primer button you won"t need a choke cable. If it is an Ensign carb, the cable will come down from the top along the right side of the carb and there should be a clamp/bracket and lever on the right side of the carb as your looking at it, this is were the cable will connect to.
Make sure the plug gap is about 0.10 Thousandths less than you would gap gasoline plugs.
You need new/good plugs and plug wires and good points for a tractor to run well on propane, This is extreamly important.
It should take a 7/8" deep well socket to remove the spark plugs.
PB Blaster is a good lube to remove most any bolts/plugs that you will have. Righty tighty, Lefty loosey.
The starter button should be a black rubber button on the lower dash panel, it may have been converted to a key start, at some point, Who knows.

I hope this helps Hal

found where the cable goes it was on the right side of the carb.does the cable run behind or in front of the air cleaner. should i be worried about water vapor in the tank when i have it filled. or just fill it and don't worry about it. also what is the starting sequence turn the propane tank knob half or all the way open. press the vaporizer button for 3 seconds start the tractor.

If you are careful you should not be getting any water in your tank. make sure your tank has caps on the fill and vent fitting. You need to protect your fill fitting on your nurse tank from getting water and dirt as well. It should not be a problem from there on out. I guess common sense needs to fall in play here. If the tank has water in it all ready, you may need to run it out of LP or blead the tank completely down and take it off to get the water out of it. Be advised that the tank could have and be partly full oil from the propane and should be drained out as well. depending on the tank it might have a drain plug in it, if not you might have to take a valve or gauge out to drain. The oil stinks! bad!
As far as starting, turn your valve all the way open, there is a seat in the valve when you open it all the way to keep it from leaking around the stem, press the primer for 2-3 seconds, leave the throttle all the way closed [idle], start the engine.

thanks for all the help the lp truck is coming by tuesday morning to fill up the tank an i will see if this monster will come to life. also iam going to buy a manual for the tractor does anyone make a manual for the lp cause i have not been able to find one. the only ones i ever find are for gas. so if you could point me in the right direction of one that would be great.

I don't know of anyone who sells LP manual supplements. I have one for a farmall 400, which is for a 4 cyl. Some of the information will be the same some could be different. I know that a 706 is set up like a 560 [6 cyl.] All LP systems are really simple and work basically the same. There is not much to them [tank, filter, pop off valve, vaporizer, mixer/carburetor] Some of the newer stuff will have electric vacuum valves and fuel valves, but that is basically it. I have 4 farmalls, a ford 860 and 2 Chevy trucks on LP and I don't have much trouble with them. A hell of allot cheaper to run, the price of fuel today.

also do you know what size the fitting is on the main valve for the tractors propane tank is. so i can hook the tractors system into a small propane bottle to get it started and drive it out of my feild. do you understand what iam talking about cause i confused myself there a little. the propane truck can not get to the tractor that is why iam doing this.

At the valve on the tractor, It should be a 3/8" flare fitting. you should be able to get a fitting/hose off of a gas grill,camper trailer, or some other propane appliance that will hook up to your 20# cylinder and at the hardware store you should be able to get/use brass fittings to get you from the threads on the hose to the 3/8 flare. disconnect the copper line from your tank, and hook up your temporary line. Make sure you check for leaks with soapy water. if you have a leak it will bubble at your new connections you made.

thanks for all the help. i haven"t setup my temp propane tank yet cause we are receiving alot of rain from hurricane gustave up here in northern mississippi. i have just a couple more questions so even tho i have a carb with a slot for the choke cable because i have the vaperizer i dont have to use it. also do you know where i can get an ignition switch and key. someone broke the key in it and destroyed it trying to get the key out [they used a screwdriver]. and do you think i should use a tank sealer kit on the tank. i am not sure but i would think there is a little water in the tank cause. there is a spout on top and i really wont to say it it the filler neak and the tractor has not been covered up. i have seen a little puddle of water of in there but nothing big just like a bottle caps amount in there. and if you have any recommendations on what to do if there is water in there. once again thanks for all the help : )

You can get a new ignition switch from your CASE/IH Dealer if you have one in your area. If not, NAPA or AutoZone or other parts stores might have a generic key switch that would work. I personally like to keep things as close to original as possible.

If your referring to the insert/valve on the top of the LP tank having water in it, this will/should not be a problem, this is the high pressure relief valve. If you were to overfill your tank [more than 80%] it will release the excess pressure if it sets in the sun on a hot day. This valve has a real heavy spring mechanism built in it and I have never seen any water get into a tank from this valve. Unless the valve is malfunctioning in some way, chances are that the valve will not let water into the tank. It would be advisable to see if you could find a plastic cap off of a new hydraulic hose or something to keep the valve from rusting closed. Most of the components of this valve should be brass, But not always. If you were to overfill the LP tank, it might not release the excess pressure and the LP tank or the weakest link/part of the fuel system may/might rupture. That wouldn't be good, especially if it was in a barn or garage. One spark and I would doubt if you could find any pieces of the building or yourself if you were in it at the time.