Green Tractor Talk banner
1 - 8 of 8 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter · #1 ·
I'm having some issues with my 1984 model 316 with the 16hp Onan. It started out with a sputtering issue that has continued to get worse. I had just changed the check valve, plugs, air filter, and fuel filter for the mowing season a few weeks earlier. I've removed the check valve and fuel filter and still have the issue. I've also now changed the fuel pump. It sputters about 80% of the time but then on occasion will purr like a kitten. Anything else to try outside of replacing the carburetor or having it rebuilt? I also always use 100% gasoline and use Star Tron fuel treatment. Any help would be appreciated, thanks!
 

·
Registered
Joined
·
1,868 Posts
You could have a couple of issues. You say YOU use 100% gas, but what about previous owner...if there was one? You may have debris in your fuel line, fuel tank, or carb. This debris can limit or stop fuel flow and then a bump can move it and everything is fine! It may also be that your ignition coil is starting to fail.

The FIRST thing I would do is put the fuel filter back in! Next, remove fender pan, fuel line and strainer from tank, and drain fuel. Remove fuel tank, add about a pint-qt. of fuel and shake the tank... HARD and a LOT! Pour fuel out into/onto a cloth and examine for particles. If you see any, repeat shaking with fuel until fuel poured out is clean! Replace pickup screen, and all fuel lines. This will give you clean fuel up to the carb. Start and run and see if it made a difference.

If no difference, a couple ways to go: rebuild carb or work on electrics. If original electrics, I'd start there. If your engine has points & condenser, replace. If only condenser, replace that!

So, we're down to carb. I don't know your skills/abilities, but you DO have the ability to rebuild the carb...even if you don't think so!

Do you have tech manual CTM2? Lots of carb into there. Before attempting a rebuild, grab throttle arm and try to move up & down, front to rear. If it moves much more than a few thousandths, the bores are worn for the throttle shaft. These can be repaired, but replacement carbs are cheap!

If shaft is snug and you decide to rebuild, get a rebuild kit. Next dismantle carb, removing EVERYTHING that can be removed! Go to auto parts store and get carb cleaner....NOT the spray stuff, but a can with a parts basket that carb parts can be put into and soaked! Put all metal parts in parts basket and soak for 2 days... lift & lower basket several times to "agitate" cleaner. Remove parts, blow out all passages with air. If you blow into a passage and see it come out of another, blow the second one also! After blowing out, spray thoroughly with parts cleaner and place on a CLEAN surface. Reassemble carb per CTM2 or instructions with kit. NOT difficult, parts only go one way!

Keep us posted as to what you've done and results. Bob
 

·
Registered
Joined
·
13,378 Posts
I would actually start with a condenser, and points adjustment. Also check the color of the spark on the points. Blue is good, yellow is weak.
 

·
Registered
Joined
·
1,761 Posts
These were known to have condensers go bad from heat, the fix is to relocate the condenser onto the outside of the engine cowling like on my 316 (sorry no picture on my phone)
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #5 ·
Thanks guys! Some great advice and ideas here. I should have a new condenser and coil coming this evening as that was my next plan and I do think they are original. Also remember when I first got the tractor someone giving me the advice to keep a spare one because they do go out. I hope to work on it some more this evening and I'll update if I do.

These were known to have condensers go bad from heat, the fix is to relocate the condenser onto the outside of the engine cowling like on my 316 (sorry no picture on my phone)
I'd love to see a pic of this if you wouldn't care to snap me a picture sometime?
 

·
Registered
Joined
·
1,761 Posts
Thanks guys! Some great advice and ideas here. I should have a new condenser and coil coming this evening as that was my next plan and I do think they are original. Also remember when I first got the tractor someone giving me the advice to keep a spare one because they do go out. I hope to work on it some more this evening and I'll update if I do.



I'd love to see a pic of this if you wouldn't care to snap me a picture sometime?
Here ya go:

785207
 
  • Like
Reactions: raiderrodney

·
Registered
Joined
·
11 Posts
Discussion Starter · #7 ·
I got her back up and running like a champ today. It was indeed the condenser causing my problems. I took AJgrn78 advice of relocating it and ended up using the same bolt as the air filter housing. I thought about extending all the way to the firewall but this seems fine.

Thanks again for all the help!


Motor vehicle Automotive tire Gas Auto part Automotive wheel system
 

·
Registered
Joined
·
1,761 Posts
I got her back up and running like a champ today. It was indeed the condenser causing my problems. I took AJgrn78 advice of relocating it and ended up using the same bolt as the air filter housing. I thought about extending all the way to the firewall but this seems fine.

Thanks again for all the help!


View attachment 785387
Great! The condenser will last much longer there, glad you got it fixed.
 
  • Like
Reactions: raiderrodney
1 - 8 of 8 Posts
Top