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MaineDad- 11-09-2008
Guys,

I took the carb off my C-160 because I have a brand new one being delivered tomorrow. I took a look inside and noticed some carbon buildup. Should I even try to remove some of it through the carb hole with a long cotton swab or something else? Or do I risk having some of that crud falling into the engine?

I know I could take the head off and access it that way, but I'd rather not at this time. What do you guys think?

MaineDad- 11-09-2008
Doing some more research, I may want to install new valves. If I buy a valve spring compressor and new valves, is it too hard of a project? Of course I would need a new head gasket too.

4StarCstms- 11-09-2008
I wish I could offer some insight into ur question...but Im like you, gonna be waiting to hear what the experts say..

Electro12WH- 11-09-2008
I would wonder why there is carbon on the carb side of the intake.

Electro12WH- 11-09-2008
If you are going to install new valves, you need to recut the valve seats and lap them in also.

Someone asked (and I forgot who) about using water to decarbon. When I was a kid a century ago, we would pour water down the carb while the engine was running. Not so much as to stall it. Just a little at a time. The water turns to steam. Then when reving up the engine, chunks of carbon were blown out the exhaust.

By the way, what are you going to do with your old carb?

MaineDad- 11-09-2008
I'll probably just box the old carb up and put it away. Unless someone wants to buy it from me.

4StarCstms- 11-09-2008
Whyd you replace it?

bluetuna08- 11-09-2008
ok...here goes...I am not trying to offend anyone...but...thank God the old days are over whtractor/yankchain[1].gif

please dont pour water down the carb because that would be bad in so many ways. the carbon build you see may be a "gum" from the gas or you valves are bad and blow by burning a little gas before it goes into the cylinder.

replacing valves is not hard if you know what you are doing whtractor/whistling2.gif

if you get new valves it is good to get a machinist to cut in new valve seats. if you run the tractor all the time it might be worth sprucing up the c-160. if you only using it occasionally than I personally wouldnt go through the trouble

buy a can of carb cleaner rather than sticking a cotton swab down in the hole. the carb cleaner will probably dissolve most of the build up anyway. although doing that isnt very good for the valve seats either but its what I would try first.

hope this helps.

MaineDad- 11-09-2008
Because it was obvious that it was in need of a rebuild. I took it off to inspect it and discovered the float was sticking, the float needle and seat were all gummed up, the bowl was all tarnished, the high speed needle was dirty and scoured, and the throttle bushing was worn. I looked into rebuilding it but found a brand new one at a great price.

sorekiwi- 11-09-2008
My take on this: smile.gif

How big a can of worms do you want to get into? If there is carbon on the back of the intake valve, then it must be sucking oil up through the valve guide. Does the motor smoke?

Maybe the valve stem is worn, in which case a new valve (with an unworn stem) may fix this. Ideally you could cut a new seat at the same time, but you could probably get away with just lapping the new valve in.

Maybe the intaket guide is worn, so now you need a guide (they're cheap), and you definately need to cut a new seat, and possibly a valve as well..

And if youre doing the intake you might as well do the exhaust as well (which are more prone to giving problems anyway....

Unless you have a seat cutter (expensive), or know someone who will come to you to cut the seats, You'll have to pull the engine and take it to a machine shop. And then there's always the temptation to say "well, since I've gone this far, maybe I should..." and before you know it you've bored it, new piston etc etc and a $700 bill.

If the motor was running OK before (except for your carb issues), I would leave it alone. If you really want to get rid of the carbon, you could turn the engine until its at TDC on compression (both valves are firmly closed at this position) and scrape out whatever you can from the port. You'll need something like a little screw driver to "chip" off the carbon. Then you could blow out all the crap with compressed air. None of this will end up in the engine because the valves are closed.

I've heard about the water thing, but dont think I'd ever do it. The version I heard though, was to spray it in in a mist, like from an old Windex bottle.

Let us know what you decide!


BTW Micah, I read your website with interest. When I move to Ohio I want a place big enough for a reasonable size garden, so I'm trying to learn the ropes now. whtractor/thumbsup.gif

MaineDad- 11-09-2008
Mike,

I agree. I'll first try to clean out what I can before installing the new carb. The engine does not smoke at all. I'm not ready, and neither is my wife, to open a $700 can of worms laugh.gif

Thanks for reading my web site. I have fun posting my experiences...

big mike- 11-09-2008
I wouldn't loose a minutes sleep over the carbon,no it's not normal but does not affect the running condition.If you replace a valve it should definately be the exhaust as the are much more prone to breakage from the extreeme heat the are subjected to.I have never seen a K series valve guide that needed replacement....the geometry of the valve train is very friendly to the guides.
Marvel Mystery oil may help with carbon build up.
Does the new carb have a high speed adjustment?If not you may want to hang on to your old carb.Without the high speed adjustment you are depending on the motor to run good at a setting determined by an engineer not having a clue as to the application the carb was going to be used in......my .02?....Walbro carbs SUCK!
If the throttle bushing is worn you may be able to find a machinist that would bore the hole and make you a new shaft.....works like a charm whtractor/thumbsup.gif

linen beige- 11-09-2008
Is it carbon or just plain dirty build up? Shoot a little carb cleaner on it, it won't hurt the valves a bit. If it's just gummy,dirty build up the carb cleaner will take the bulk of it right out. If it is carbon you may be able to grind or just hand lap the old valves and give her more hours to live. If the seats don't have warpage or pits in them or a groove burned in them they don't need to be replaced. If the old valve is not chipped, warped, or burned down so thin that grinding, lapping will remove enough margin to allow it to close too far into the seat and stick, then a little elbow grease with some lapping compound might be all it takes. Even if that doesn't work, you have not hurt any parts that didn't already need to be replaced. Only spent a little time learning a new skill.

A fine mist of water into the intake of a running engine will soften carbon build up in the combustion chamber without hurting the engine. Water injection kits are still being sold, and they do work. But it won't have much, if any effect on any carbon in an intake (or exhaust) because there is no compression/combustion working to loosen it up.

htopjimmy26- 11-10-2008
Just curious , did you buy a new Walbro non adjustable carb? I would like to know after you get it installed how it runs. huh.gif As to the carbon my 2cents aren't really worth the powder to blow 'em up but.......a little black soot/dirt/carbon is probably normal and nothing to worry about, Kohlers are dirty rugged little pigs that were engineered in the late 50's?, not formula 1 engines biggrin.gif whtractor/hide.gif . If you can't chip a big hunk off then it's probably nothing to worry about. If you decide you must clean it out probably the thing to do would be pop the head off, then turn crank until the intake valve opens and hose her down with carbclean or ether[with carb off]. Good luck whtractor/thumbsup.gif

htopjimmy26- 11-10-2008
BTW, if you smoke ingnore the ether part! biggrin.gif

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