GP Questions

I have been offered a John Deere GP from a sales man that we do buisness with at work. It was his dads tractor. Looks to be complete with a very tall air intake and exhaust stack. It has been sitting for 20 years, and the motor is stuck. It is covered with pine needles in the two pictures I have. It has round spoke wheels in front and flat spoke wheels on the rear. Tires are poor almost bald. I had a 1944 D John Deere years ago so I'm not totally unfamiliar with the old two cylinder JD's. "What is somthing like this worth." I looked on Yesterday's Tractors. My tractors and other tractor forums but did not find much on one this old. Looks like they were made from 1929 - 1935. They are kind of a neet old tractor, but 35,000 were made so not as rare as my 1937 WF Allis Chalmers with only a total of about~8000 made or so. I have thought about getting back into the old tractor collecting again but NOT like I was in the past. I had ten old tractors at one time twenty years ago. Now all I have is my Allis, a 10-20 Mc Cormack Deering and My 4010 JD.
By looking at pictures of the standard GP's on the Internet, there seems to be a difference of which side the exhaust exits. The tractor I'm dealing with, the exhaust is on the left as you sit on the tractor, others that I have seen have the intake on the left. Can someone shed some more light on the differences on the GP? I'm guessing it might be small bore pre 31 verses the big bore 31 and later? Some seem to have a tall exhaust some very short or no pipe at all. Some have a air intake though the hood some are beside the hood. I have tried looking for a JD enthusiast that would have an article on the GP but have not found anything.

We really need a picture to see what this GP really is. A big bore GP has the air stack on the flywheel side and the exhaust on the pulley side. I have a couple big bore GP's and they are unique tractors. There may have been quite a few produced but the survival rate isn't great. They were were aimed at working row crops in three's not two or four rows and there were some weak points in the design. A nicely restored GP is a real eye catcher.

I will get some better pictures next week. From what you say, and pictures that say year of the tractors, it must be a 29 or 30 small bore, as the exhaust is on the flywheel side. Air stack is outside of the hood on the right front, and very tall like the exhaust. Fenders are not very good from the two pictures I have on my work computer, the right fender has damage in the rear. I'm going to bring a scoping camera and look inside each cylinder through the spark plug hole. The owner said the wheels are solid and not rusted though.

(quoted from post at 17:11:58 11/04/16)

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hotobucket is down so no pictures

Do not get excited about either Bore size..the difference is minimal, 1st gear is pretty fast and all the gears are pretty close is speed..

The Small Bore GP will (Just Barely) pull a Clean 2x14" plow if it is fairly good running..

Seems the GP with the Short Exhaust ( that points down) usually are not "Stuck"..the ones with the upward exhaust get water in the engine..

17.24 HP at the Drawbar and 24.97HP on the Belt when new...

The fast 1st gear limits it's use and slow 3rd gear the same.. 1st: 2.5 mph 2nd: 3.12mph 3rd:4.33 mph...

The Early
(1934-1941) "A" had similar HP (Slightly More) but did have 4 gears..

Can't get the thumbnail to show it right sorry if it turns out sideways

That's a small bore tractor. They were rated 10 on the draw bar and 20 on the belt. It
looks fairly complete so it should be a better candidate to restore. What magneto does it
have.

I don't know any details yet. He said he had spare Magneto and some steering parts. As you can see the wheels are not parallel in front. Being it deer season opener here in MN, he was busy this weekend but I'll go look/ buy it one evening this week.

I went and looked over the GP today, serial number is 219514 which makes it a 1930. It is very complete and I did not find any broken castings. There was water in the left cylinder even the valve was open. Right cylinder might be OK. Fair Banks Magnito on it and he has a spare when he finds it. Tires are still up but shot. Somebody put spacers below the tank supports thats why the hood doesn't sit down on the radiator. Tank has a little rust but not everywhere some galvinizing still on most of the bottom. All covers and caps were inplace so the radiator core looked good from inside. I'm going to pick it up and haul it home on Tuesday next week.

I'm going to need new fenders for sure, and maybe some rings and head gasket. I tryed to put a camera scope in the spark plug holes but it was to big to see much. The valves were clean from what limited sight I had. Where is a good place to get some of the parts for this GP? Someone must repop the fenders, if not, my neighbor has a roller and we might be able to roll some ourselves.

I hauled it home today

Well I was able to get the 1930 GP into my garage today and started to disassemble it. I knew the left cylinder had water in it before I purchased it. I was hoping it wasn't to much rust and after a couple hours I had the head off and now I know. The first and second picture is the left cylinder that had the most water, the top of the cylinder has the most rust, but I don't think it is really that bad. I've restored worse. The third picture is the right cylinder. Looks nice to me with very little if any rust.

What do you John Deere guys think?

As you can see the left cylinder bottom I scraped with a small putty knife and it cleand up very easily. The top I did not scrape at all. I sprayed both cylinders with penetrating oil and quit for the night. The valves and seat will need to be reconditioned as thats where the water came into the left side cylinder. All valves move freely and are not stuck. I should be able to grind the seats in-place and just re-ring this motor. It is standard bore 5 3/4" and I did not even see a ridge at the top of the right "good" cylinder.

Well I purchased a strong back puller at NAPA and used two head studs, a 5.700" dia X 3/4" thick slug of steel to protect the top of the stuck piston. It was fairly easy to get the piston to move
I unbolted and moved the cylinders forward and out away from the crank case as I pushed the piston back. Right piston came out first and is in excelent shape, the left is not all the way out yet, 3" is left in cylinder, I ran out of length with my puller/pusher bolt. I'll need to get more of a spacer to be able to finnish it, but it is well under way to getting this GP running again. Looks like I'll need for sure, head, base gaskets, exhaust valves, set of rings, and wrist pin, I want to bore and sleeve the rust damaged left cylinder, grind the valves/seats and make a few smaller gaskets. The crank shaft and lower end looks to be in good shape, even though water from the left cylinder made its way into the case it does not have any rust it the crank area.

Well, after several months of working on the GP. I rolled it out of my garage, put some water in the radiator, a little gas in the tank, and it, Fired right up! I don't think it turned over four revolutions and it was running, rich at first, but a little adjustment to the carb and it was good.
Lots of things repaired, both cylinders sleeved, new exhaust seats and all new valves, faced off both the block and head, rebuilt governor, new clutch discs, soldered gas tank and sealed it, rebuilt the front axle kingpin bushings and thrust bearings, straightened tie rod, re-rimed rear wheels, still need to do the front rims, repaired rear fenders ( not finished yet) with the fenders.
I have a small water leak from the lower radiator tank gasket and a few small oil leaks to repair but it is comming along.
I had a broken casting on the original exhaust so I made a new SS one. I took quite a few pictures of the rebuild and videos of me machining the cylinders but I don't know how to get videos to load.

The same left cylinder.
And the new studs and valves.

I forgot to mention I rebuilt the carb too. The original cork float was still in the carb. I rebuilt the air cleaner, crank case vent, and straightened all the radiator fins. I'm sure I missed something else I've done to this GP.