JD 3020 Runs rough at full throttle

Posted by rbeissel on September 04, 2023 at 14:33:16 from (67.4.68.192):

I purchased a used 1968 JD 3020 gas tractor with a Zenith carburetor last spring and finally had it out on the road last weekend. After running the tractor a few miles and up to temperature (but not running hot), the tractor would run fine but I noticed the engine would start to spit and sputter when going up hills. Running on flat road or downhill there was no problem.

I started to observe closer how it was running and found the following:
Running at full throttle, 2000 to 2200 RPM and going uphill the engine would start to spit and sputter and RPM would drop the point of almost stalling (like someone shut the engine off). When the engine got to the point of almost stalling, I would push the clutch in and reduce the throttle to 1500-1600 RPM and the engine would seem to recover and come back alive. I down shifted to get up the hill and the tractor seemed to handle it ok and maintain RPM up to the point of about 1800 RPM. If I throttled over that it would start to spit and sputter again.

My thinking is the gas filter is probably getting plugged and starving the engine for fuel. When climbing the hills under more of a load it wasnt getting the fuel it needed and started stalling. If this was an electrical issue (i.e. lack of spark), my guess would be the engine would load up with gas and when the spark came back would possibly backfire?

I will be replacing the gas filter and testing the fuel pump pressure this week. As well I will be checking the screen at the inlet of the carburetor and cleaning as needed. Ive also got new spark plugs I will be installing as well since its not known when they were last changed.

My question is, am I on the right path with this and is there anything else anyone can think of that would be good to look for?

Replies:

• Re: JD 3020 Runs rough at full throttle super99 16:19:57 09/04/23 (0)
• Re: JD 3020 Runs rough at full throttle casecollectorsc 14:58:33 09/04/23 (0)
• Re: JD 3020 Runs rough at full throttle rustred 14:55:35 09/04/23 (0)
• Re: JD 3020 Runs rough at full throttle Bob Bancroft 14:39:29 09/04/23 (0)

Add a Reply! You must be Logged In to Post Name: E-Mail: Subject: (avoid special characters) Comments: Optional Link URL: Link Title: Optional Image URL: Optional Video Title: Optional Video Embed: Advanced Posting Options Email Notification: If you check this box, email will be sent to you whenever someone replies to this message. Your email address must be entered above to receive notification. This notification will be cancelled automatically after 2 weeks. No political comments, hate speech or bigotry of any kind will be tolerated. Violations will be removed and posting privileges may be permanently revoked without notice.   Advanced Posting Tools   Select Gallery Photo  Attach Serial No List  Return to Post  Upload Photos/Videos Choose Files from your local computer Upload one or more videos to your post. Photo and video filesizes should be less than 5MB. Formats allowed are gif, jpg, png, ogg, mp4, mov, and avi. Be sure to use filenames without spaces or special characters, and filetypes of 3 digits lower case.

TRACTOR PARTS	TRACTOR MANUALS

We sell tractor parts!  We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]