AF30 mystery... uphill stalling but not uphill backwards

Post your questions or problems you are haviing with your Yanmar tractor here.

Moderator: Aaron

YanFan
Volunteer Poster
Posts: 1
Joined: Sun Sep 10, 2017 10:47 am

AF30 mystery... uphill stalling but not uphill backwards

Postby YanFan » Sun Sep 10, 2017 11:14 am

Hi there, I have an AF30 Yanmar which has been a great workhorse for some time now. Documentation for it seems rather scarce and the problem I'm experiencing is somewhat frustrating: the tractor has a tendency for stalling 'episodes'... that is, not consistently. IF it happens, this ONLY takes place when travelling uphill (forwards). This problem does not occur travelling uphill backwards(!). As soon as a level location is again reached and a few minutes pass, the stalling no longer occurs and everything seems normal again. My suspicion is that it's fuel-related, however, looking at the fuel lines, can it be that this tractor has 2 tanks (under the foot plate, one on each side). I assume that the only possibility is some sort of foreign matter periodically clogging the fuel intake line... at other times it might be happily swimming around the tank(s). Tried running without fuel cap (vacuum lock check) but no noticeable difference. It sounds like a fuel pump is chugging away happily at all times as well (as tank below engine on this model). Any suggestions, please? Maintenance has been regular (fuel filter, air filter, oil etc.). Carefully warming it up prior to use etc. Occurs with/without loads, soon after starting out or towards end of working session.

Aaron
Site Administrator
Posts: 2437
Joined: Thu Jul 26, 2007 12:39 pm
Location: Iowa Park, TX

Re: AF30 mystery... uphill stalling but not uphill backwards

Postby Aaron » Mon Sep 11, 2017 12:20 pm

I'm not going to be much help on that one. I don't even have a parts book on any of the AF models. I agree that it sounds fuel related. It could also be electrical though if you have an electric fuel pump and electric shutoff. It might be something like a wire with a bad spot that loses connection at a certain position. Troubleshooting those intermittent problems is tough.

Aaron
Site Administrator
Posts: 2437
Joined: Thu Jul 26, 2007 12:39 pm
Location: Iowa Park, TX

Re: AF30 mystery... uphill stalling but not uphill backwards

Postby Aaron » Tue Sep 12, 2017 10:01 am

From what I have found the AF series Yanmars were a joint project between Yanmar and Shibaura which might explain why they are so much different than the other 'F' series.

Norm
Volunteer Poster
Posts: 2697
Joined: Sat Feb 16, 2008 10:08 am
Location: Ft Lauderdale Fla./Trenton Ga.

Re: AF30 mystery... uphill stalling but not uphill backwards

Postby Norm » Wed Sep 13, 2017 5:39 pm

it's almest definitely a fuel related problem, but if you seriously do not know how many fuel tanks you have or their location I don't see much hope for troubleshooting.

alan
Volunteer Poster
Posts: 2665
Joined: Sat Oct 06, 2007 6:25 am
Location: West of Toronto

Re: AF30 mystery... uphill stalling but not uphill backwards

Postby alan » Wed Sep 13, 2017 8:04 pm

I googled the AF series to see what it was and came across a major supplier in Osaka -- that might be able to help.
mish-tractors.jp


Return to “Tech Support”

Who is online

Users browsing this forum: Bing [Bot] and 2 guests