Author	[Modern View]
dustin1706 08-24-2012 17:43:39 172.219.71.189 Report to Moderator	Hello, I have a 4020 that I cannot get to start and I am hoping that someone can give me some guidance. The tractor is my fathers and basically, 15 years ago it would not start, he had some sketchy mechanic try to get it going and has been sitting in a shed since then. I would like to get this tractor going to use for snow plowing etc. I believe the tractor is around a 1968 with a cab and hydrostatic drive. I first changed the fluids and filters, cleaned out the fuel tanks etc. Then after cranking it over, it seemed that the injection pump (roosa dbg) wasn't putting out any fuel. The lift pump works fine. So I took the roosa apart, cleaned everything, changed the o rings with a rebuild kit. It was pretty much perfectly clean to start with, but I found that one of the tiny springs that connects the transfer pump blades was broken, so I replaced the springs and blades. Also, inside the "lid" of the pump there are two holes for a pin to go into, one is C and one is CC. The pump turns counter and everythign in the pump has the CC up, but this pin was in the C position. I changed it to CC. This pin adjusts which direction the eccentric transfer pump outer housing sits in. Not sure if it was always like this or if that "mechanic" changed it. Also, I am not sure if the pump is in 180* from what it should be. The tip of the pump shaft isn't symmetrical and only seemed to want to go into the engine in one direction so I assumed that was correct. In any case, I do get some fuel through the injection pump now and I bled off all of the lines with fresh fuel including the return line. However, I cannot get this thing to fire at all. I took off the valve cover to check for bent pushrods etc, but everything seems fine. If I put my hand over the intake manifold it will nearly suck my hand in. Even with ether, I can't seem to get even one hit..... I get no smoke out of the exhaust. Shouldn't this tractor fire on ether even if there is no fuel? Or does it need diesel as well and I still have injection issues? Is there a decompression lever? Any ideas for me? Thanks! Dustin [Reply]   [No Email]
teddy52food 08-25-2012 07:16:13 184.94.175.179 Report to Moderator	Re: John Deere 4020 Will not start in reply to dustin1706, 08-24-2012 17:43:39   Better pull the injectors & get some oil in there. After setting for 15 years & then using ether it has lost its compression.   [Reply]  [No Email]
Tx Jim 08-25-2012 04:00:23 67.142.163.22 Report to Moderator	Re: John Deere 4020 Will not start in reply to rustcollector, 08-24-2012 17:43:39   dustin1706 Did you time engine to #1 TDC before removing inj pump??   [Reply]  [No Email]
Mike Aylward 08-24-2012 19:12:36 216.145.134.145 Report to Moderator	Re: John Deere 4020 Will not start in reply to dustin1706, 08-24-2012 17:43:39   Dustin, the pump rotation is expressed as viewed from the drive end. It sounds as though your transfer pump liner is backward. It will not pump fuel if it is backward. Put it back like it was and it should work fine. Mike   [Reply]  [No Email]
jdv 08-24-2012 22:56:04 67.209.220.236 Report to Moderator	Re: John Deere 4020 Will not start in reply to Mike Aylward, 08-24-2012 19:12:36   It should fire on either. your not getting it to the right place. Make sure the rocker arms move when you turn it over.   [Reply]  [No Email]
dustin1706 08-24-2012 23:00:52 199.87.51.162 Report to Moderator	Re: John Deere 4020 Will not start in reply to jdv, 08-24-2012 22:56:04   Quoting Removed, click Modern View to see Yeah, that's the thing that confuses me most and had me wondering if there is a decompression system. If I feed it ether it should fire regardless of fuel/electrical etc.. Right? Rockers are all moving, valve/rocker clearances are maybe a tiny bit loose, but reasonable. I've got the air filter off and I'm feeding it the ether right into the intake manifold. Like I say, if I put my hand over the intake manifold it has some serious suction.   [Reply]  [No Email]
dustin1706 08-24-2012 20:28:11 199.87.51.162 Report to Moderator	Re: John Deere 4020 Will not start in reply to Mike Aylward, 08-24-2012 19:12:36   Quoting Removed, click Modern View to see AAh, I see. I tried to find out which way it was when I was reassembling, but couldn't find it. I was placing the parts on a table so i wouldn't lose the original orientation, not realizing that the pump could be assemble dfor C or CC rotation. But, then I had the transfer pump apart a few times when I realized that spring was broken. I just hope I have the cam ring installed properly. I did punch a sharp line across the pump flange to the block so that I could keep the original timing, maybe i should rotate to TDC and make sure I'm not 180 off as well. Still though, shouldn't she fire on ether regardless? Thanks very much guys!   [Reply]  [No Email]
john deere haverstor guy 08-24-2012 18:17:25 66.82.20.123 Report to Moderator	Re: John Deere 4020 Will not start in reply to dustin1706, 08-24-2012 17:43:39   When you take the pump off a 4020 you got make sure it is timed up right when you put it back on. There are marks on the Flywheel for this. There should be a square shaped flap on the bell houseing on the right side of the tractor that slides open so you can properly time it up.   [Reply]  [No Email]