Plugs fouling

[Phillip W. Lenke]

I am on my fourth set of plugs. Champions,ngk's ,autolights. Got hotter plugs also. my son ran it for almost three hours pushing snow. Brought it back up, ,carboned up terrible, when I got home from work, expecting to get on it and plow , ended up replacing plugs, and still it not running smooth at high idle. HELP! I've had the carb apart numerous times, cleaning it. But I do know from personal touch, it is a HOT mag.ouch! Got to be something small. But I'm getting frustrated.
Phil

[Bigdog]

Phil, is there oil consumption or is the fouling strictly from running rich?

Has this engine had any work done to it? Can you give us a general description of the condition of the engine? Compression OK?

[Phillip W. Lenke]

The engine was overhauled with new rings,valves etc. Not sure on the compression. Feels good though.

[Bigdog]

Is this on your cub?

[Eugene]

http://www.centuryperformance.com/vacuum.asp

There is a possibility that the rings have not seated yet on a new overhaul. Although this shouldn't be fouling plugs to this extent. Another possibility is that the person who overhauled this engine did not get the rings installed properly.

Suggest two tests. One is the compression test, wet and dry. The second is the vacuum check. Web site on vacuum testing is posted above.

Eugene

[George Willer]

Phil,

It's possible the main jet has been enlarged some time in the past, causing it to run too rich. In any event, for whatever reason it must be too rich. It would be easy to change the jet to see if it makes a difference. I'll loan you one.

I'm sure you've made sure the air cleaner isn't obstructed.

It's amazing what happens some times when people change proven things to try to improve performance!

[cowboy]

Mr G.W.

There is some real truth there I fixed rebuilt cleaned flattened my carb re cleaned and onec agin. And still rich as WK would have us belive the fuel has changed so much in the last 40 years and that is the cause and that I belive may be half right. Call me a cowboy but the other half I belive is torch tip cleaners. Most farmers have torches . Unlike Bill who has phone wire what do the rest of us grab to clean a small hole that is close to hand Enought said.

Billy

[beaconlight]

Billy you may be a cowboy but you don't keep your brains near the saddle. I never would have thought of it but torch tip cleaners sure could do it.

Bill

[WKPoor]

This subject keeps turning up from time to time. I agree completely with GW's responses to the subject. The thing that puzzles me is this product does seem tempermental to this condition as so many have an issue with fouled plugs. Also I'm wondering if George himself has ever ran across the problem. George, Carl and others have a really good handle on the fix but with all the tractors they posess you would think in some form or another that they would have experienced it also. Now if there are tractors out there that run reliably year around with no fouling issues at all then it would be nice to know what that exact formula is. We also need to hear from people who uses their tractor alot during the winter months where the problem is at its greatest. It maybe just making sure your machine is tuned exactly per the book which I'm sure is 99% of it.
Carm! where are you.

[Phillip W. Lenke]

call me a beginner on IH carbs The main jet, the brass tube about 2.5 inch long? One fellow I talked to said it could be the float height, is this possible:?:
GW I may come out with the carb and see if we can go through it when you feel up to it.
Phil

[Dale51]

I have 4 IH carbs. one is incomplete so I don't know how it works.
Out of all 4 I did find this. No two of the main that you refer too are the same size. One I know came off of a power unit it has the biggest of the 4
next it one that came off a 67 lowboy then a 51 then a 47.
You don't need to measure them you can see it plain as day.
I would take GW up on his offer and try it.

One other thing I would try first is unhook the air cleaner & see how it runs as some of the oil gets on the bottom of the cleaner and is very thick this time of year and could be acting like a choke.

Yes the float could be part of the problem .
In the past I have set floats to spects & it just would not run right
and I had to set the float lower or higher as needed to fix the problem.
I your case I belive you would have to lower the float.
PS: a thirty second of an inch will make a diff.
The besy way to set the cub carb is the ol clear hose trick!!!

[Phillip W. Lenke]

Refresh my memory. Clear hose trick.

[Bigdog]

Phil, take a look here:
http://www.cleancomputes.com/Cub/Maintenance%20Tips%20and%20Techniques/Lurker%20Carl's%20Cub%20Carb%20Fixes/Fuel%20Level_files/frame.htm

[George Willer]

call me a beginner on IH carbs The main jet, the brass tube about 2.5 inch long? One fellow I talked to said it could be the float height, is this possible:?:
GW I may come out with the carb and see if we can go through it when you feel up to it.
Phil

Phil,

No, the main jet is the hex nut looking thing on the near side, accessible from the outside. A 3/8 wrench will have it out in a jiffy. Be careful not to lose (note spelling ) it.

Since I have a few of them loose (note spelling ) on the bench I'll check the sizes and report.

The float setting may play a SMALL part in the mixture, but I've not been very obsessive about it and don't have problems. I agree that lower level = slightly leaner.

Give me a call... we can go through the carb any time.

[Phillip W. Lenke]

Well I changed out the main jet as posted on main jet sizes. Drastic change in engine smoothness. Plowed snow for almost 2 hrs. Ran like a champ.
I made a new oriface, changed to .030-.032 . Will check plugs later. No heavy fuel smells like before. Hope this helps with someones future issues. Did mine AAAHHH!
Phil