DB885 Starting Problems

Can someone diagnose this?


[video play=false:c81d62c5e7]https://forums.yesterdaystractors.com/videos/mvvideo27170.mp4[/video:c81d62c5e7]

A little background. I have NEVER had a problem starting this tractor from the day I got it.

Here's what happened when the problem started. Thanksgiving night I was unloading a gun safe from the back of my pickup. I had the Brown backed up to the truck with a platform on the back to load the safe onto. The tractor was idling for approximately 20-30 minutes as I had to retrieve a rope from the barn to pull the safe to the rear of the tailgate. As I began to move forward, the engine began to race, revving up to approx 1800 rpm, but then it settled again to idle, 750rpm. I put the tractor in reverse to back to my house door and it revved again, for about 4-5 seconds, then settled again. I backed the tractor to the door and shut it off. I was unloading/moving the safe into the house for about 20 minutes. I returned to the tractor, tried to start it, and it did what you see in the video. I finaggled w/ it for about 10 minutes and it eventually started. I parked it in the barn until today.

This evening, I noticed when starting it, the tractor was a little more hesitant than usual. It started on the first turn but it wasn't as quick as normal. I attached my hay spear, drove to the hay barn, got a round bale, removed twine and parked the tractor back into my barn. All this took maybe 30 minutes. I thought I'd try to restart the tractor to see if everything was OK. It wasn't, the video is from this evening. I walked away for about 5 minutes, went back and it started. Turned it off and it went back to this. I did get it started a second time after 10 minutes or so. Shut it down and this again. I did notice a few times that the tractor seemed to "burp", nothing big, just a short, almost grunting sound.

I don't believe it to be electrical, as I can continue to turn the key and it attempts to start for a couple of 10 minute sessions. It almost as if there's something keeping the engine from turning over. I can feel the crankshaft turn over then stop abruptly, like it feels as if it gets stuck.

Thanks for any help.

Any time my diesels rev up for no reason it usually means they are low on fuel or something is blocking fuel flow. I'd change the filters and make sure she had a good fuel supply first. Any white smoke showing when she acts up? That's often water in the cylinder from a head gasket or cracked head leak.

The video shows a weak/dead battery or dirty electrical connection.

I have also seen them do this when a brush was hanging up in the starter.

How old is the battery? How big is it?

Starting problems with diesel electrical systems generally show up when the weather turns cold.

I think I have the starting problem solved. I've both jumped the battery today and charged it on a charger. Both times the tractor started without so much as a hiccup. That tells me, the battery is bad.

Now, to figure out this revving issue. It's almost as if the tractor is loading up on fuel while idling. If accelerating after a lengthy idle, such as during a 3-pt implement hookup, the motor will sometimes "chatter". Almost like a clapping/knocking sound. Once this ends, the engine runs like a top, and it has after the revving, also. The revving just scares the hell outta me every time it happens!! It lasts for maybe 3-4 seconds, I'm just afraid it's not going to stop sometime!!