D15 Carb

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   Was raking hay the other day and engine started surging, then wanted to die. Suspected it might be the carb, so hopped off and turned rich/lean adjustment screw out and after about half a turn, she smoothed out and ran fine after that. 

Trouble is that screw is almost loose enough to be floppy and problem may have developed by screwing itself in. Tried to tighten the smaller of the two nuts and it is more or less as far down as it is going. Does that have some form of packing in there that can be or needs to be replaced? Or......how does one firm that screw up so setting doesn't wander? 

I assume for best fuel economy for light duty use like raking hay, one wants it running as lean as it can?  Right now it is about 3 turns out. 

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modirt Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 18 Jul 2018 Location: Missouri Points: 8439	Post Options Post Reply Quote modirt Report Post Thanks(0) Quote Reply Topic: D15 Carb Posted: 21 Jun 2025 at 4:51pm
	Was raking hay the other day and engine started surging, then wanted to die. Suspected it might be the carb, so hopped off and turned rich/lean adjustment screw out and after about half a turn, she smoothed out and ran fine after that. Trouble is that screw is almost loose enough to be floppy and problem may have developed by screwing itself in. Tried to tighten the smaller of the two nuts and it is more or less as far down as it is going. Does that have some form of packing in there that can be or needs to be replaced? Or......how does one firm that screw up so setting doesn't wander? I assume for best fuel economy for light duty use like raking hay, one wants it running as lean as it can? Right now it is about 3 turns out.

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steve(ill) Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 11 Sep 2009 Location: illinois Points: 86684	Post Options Post Reply Quote steve(ill) Report Post Thanks(0) Quote Reply Posted: 21 Jun 2025 at 6:11pm
	3 turns out is normally i little excessive.. It might mean you have a little piece of crap plugging a jet inside.. I have wrapped teflon tape on the threads to tighten things up somewhat.. a coil spring under the screw head can also help... if it has a head on it..
	Like them all, but love the "B"s.

Kenny L. Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 12 Sep 2009 Location: NEIOWA Points: 1344	Post Options Post Reply Quote Kenny L. Report Post Thanks(0) Quote Reply Posted: 21 Jun 2025 at 6:26pm
	Modirt, Text me your address and I will send you something that will fix you right up it's off of the packing that was use on the water discharge pump on the wash plant that I run at one time. I did have your address but miss place like a lot of stuff around here. I text you. Kenny Loughren. Edited by Kenny L. - 21 Jun 2025 at 6:31pm

modirt Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 18 Jul 2018 Location: Missouri Points: 8439	Post Options Post Reply Quote modirt Report Post Thanks(0) Quote Reply Posted: 9 hours 27 minutes ago at 2:17pm
	Was raking hay yesterday and tractor started to act up. Lost most power then began to sputter. Got the rake off, then limped 100 yards or so up the road to neighbor's shop. Told him about the carb (jet screw was now spinning freely and had play in it) so he pulled the jet, (gas leaked out which may have back flushed and crud out), then put a wrap or two of Teflon tape on it for packing and back in she went. She started and after screwing in the jet till the rpm's started dropping off.......we backed it out about 1/4 to 1/2 turn and she smoothed right out. Ran it for an hour today pulling a hay tedder and she never missed a lick. Back from the dead. Always amazes me how badly off a perfect running tractor can get if the carb is off by even just a little. Lots of critical links but that one has to be close to the top of the list of potential troublemakers. Diesel pump and injectors far more reliable. Edited by modirt - 9 hours 26 minutes ago at 2:18pm

DSeries4 Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 12 Sep 2009 Location: Ontario, Canada Points: 7468	Post Options Post Reply Quote DSeries4 Report Post Thanks(0) Quote Reply Posted: 8 hours 1 minutes ago at 3:43pm
	Might want to clean out your tank and replace the screen in the sediment bowl while you are at it.
	'49 G, '54 WD45, '55 CA, '56 WD45D, '57 WD45, '58 D14, '59 D14, '60 D14, '61 D15D, '66 D15II, '66 D21II, '67 D17IV, '67 D17IVD, '67 190XTD, '73 620, '76 185, '77 175, '84 8030, '85 6080

modirt Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Access Joined: 18 Jul 2018 Location: Missouri Points: 8439	Post Options Post Reply Quote modirt Report Post Thanks(0) Quote Reply Posted: 5 hours 31 minutes ago at 6:13pm
	Tank is clean. No crud.....no water, no rust. New sediment bowl, with new screen. As of today, running like it should. Love listening to that little engine work.