Wheel Horse C-81

[diggerjames 543]

And will then cause your symptoms

[Ian 2,417]

If the main mixture screw is broken then that's where I would start with your running problem Norm.. The question is has it been broken by getting knocked or has it seized and someone has snapped it while trying to get it out!!

 

I don't know if your 8hp engine uses the same mixture screw as a 10hp, if it does I'm sure I've got a spare your welcome to.

[Stormin 4,458]

I'll not have much time tomorrow but I'm going to remove the float bowl in the morning. It's got a weep anyway. I've the trailer to collect and bank to rob in the afternoon. Then get loaded. It'll be at Newby so the experts can have a look.

[meadowfield 1,900]

I'll not have much time tomorrow but I'm going to remove the float bowl in the morning. It's got a weep anyway. I've the trailer to collect and bank to rob in the afternoon. Then get loaded. It'll be at Newby so the experts can have a look.

If you find them, send them our way

[Stormin 4,458]

Mind you, getting it on the trailer could be fun.

[Stormin 4,458]

  Started it up this morning and it ran OK. But only on idle. As soon as I tried to give it some throttle it would rev then die. Everything points to fuel starvation, either the pump is not working right or the carb needs cleaning out.

  So It looks as if I wont be taking it to Newby. Disappointment is an understatement.  When I get back it will be carb and pump off.

[diggerjames 543]

Why dont you bring it and surely between us we can sort it out ! It can be our project over the week end

Cheers James

[the showman 4,074]

Yeh, as James says bring it and we all can have a look at it. its only an engine !!

[pmackellow 2,728]

Bring it along Norm, let the lads have a play !!

[meadowfield 1,900]

We need some evening entertainment.

Last year we had the carb off a Bristol crawler in bits Saturday night

[Stormin 4,458]

You'll be pleased to hear the C-81 is on the trailer.  So you can have a play.    BTW. It drove on under it's own power.

[meadowfield 1,900]

Great news

[Ian 2,417]

That's good news Norm, what did you do to the carb to make it usable?

[Stormin 4,458]

Haven't done anything Ian. Ticks over nicely. Just enough to make progress. Dies if throttle opened up. Need another carb, Float chamber wrong as well as broken main screw. That's on the side and not top.

[Stormin 4,458]

  Chris down in West Sussex sent me up another carb off a Kohler 8hp. Minor differences but ALL mixture screws intact. Many thanks Chris.

  Finally got around to fitting it today, but first a float bowl seal had to be made. I found an O ring that fitted the groove but the diameter was too big. Stanley knife and Super Glue sorted that. Carb cleaned and put on. Started up but the engine would still not run right. Much popping and banging at high revs and flames out of the silencer. Black smoke as well. Running rich. Flooding? Float bowl off, float needle seemed free and just a little fine dirt in the bowl. Mixture screws out and a blow job with the airline. Reassembled and things a little better, though not by much.

 Checked the condition of the points. A little clean up and reset sorted them.

 Much fiddling followed and I noticed the pump feed to carb union was leaking a little bit. Off with pump as the union could not be sorted in situ. While off I took it apart to check the diaphragm. It was ok, but the inside of the pump was a tad dirty. Cleaned it and replaced on the engine.

 Restarted and still ran erratic with black smoke from exhaust and would only run at high revs. More fiddling with the mixture screws and it runs much better now. Well it did before I came in for a coffee.

  I also changed the position of the governor arm to carb linkage position. Moved it to the lower hole on the arm. Gave more movement so I assume I'd fitted it wrong. BTW.I didn't take it apart.

  I'll run it again later and see if it's still OK.   

[Anglo Traction 998]

Good news on the running improvements Norm. I take it the old Carb was a Walbro?. Also , just wondering what the state of the Air Filter is like?. They can also really screw up your mixtures and settings if they are dusty or Oiled  .  

[meadowfield 1,900]

good news, got there at last!

[Stormin 4,458]

Air filter's not to bad, Richard. Makes not difference on or off.

 

Mark, sad to say not there yet.

 

It will rev now, but idle is not as sweet as it was with old carb. It's running rich and takes no notice of idle mixture screw. Anyone know the float setting. And yes, Richard, a Walbro.

[the showman 4,074]

try these

[Stormin 4,458]

Thanks Chris. Try that tomorrow.   Here's hoping it works.

[Stormin 4,458]

  Further to more info, I've found that the original carb has not got a broken screw after all. It didn't have one to start with. Being a later model carb it is a fixed jet. All to do with emissions. It still has the wrong float bowl though.

 

  I checked the float settings on both carbs. The older carb has a brass float, the later one plastic. I set the height of the brass float but was unable to set the drop. The tag, as in Chris's diagram, is missing.

 

 The plastic float, much bigger than the brass one, was ok for both settings. Unfortunately they are not interchangeable and neither are the float needles.

 

 The older carb is now all together and on the tractor, ready to try tomorrow.

 

 One thing for sure is I'm learning about the carbs.

[the showman 4,074]

sounds like you've become a bit of an expert Norm, fingers crossed for tomorrow then

[Stormin 4,458]

More than fingers crossed, Chris.

[Stormin 4,458]

  Well it runs and not as rich now, but it's still erratic. It seems to be t'other way round. a bit lean. I can get anywhere near the lovely idle it had with the original carb. It also seems to have quite a bark now.

  I took the original carb to the garden machine centre, I frequent. He's going to see if he can find a float bowl that fits. When I get that, I'll refit and see what transpires. Until then I'm leaving it alone. (Maybe?)

  I've got a question though. In which hole does the connecting rod from governor arm to throttle go.? The top one in the arm or the lower one?

[Stormin 4,458]

  Today, well yesterday afternoon actually, I decided to attack the C-81. The original fixed jet carb was cleaned up, cleaned out and re-assembled. The float bowl is the correct one as it is the same bowl as the C-120. Difference being the 120 had a gasket which I copied.  

 

  Re fitted the cleaned up carb today and started up. Ran a bit better, but the throttle and choke had to be juggled.  I wasn't happy with the throttle action. Rather stiff compared to the C-125s.  So all that was removed, cleaned up and replaced. Not a lot of difference made.

  

  So back to starting it p and playing with the idle screw. At one point it stopped and refused to re start. This had me a little perplexed.  That was until I looked in the petrol tank. I could see the bottom.

 

 Now with fuel in, off we went again. Things are better now but not as I would like. Still can't get a nice smooth idle, but it runs and drives ok at wider throttle openings.

 

 Another thing on the list is a quieter exhaust. This one is a bit too noisy for my liking.