Going Downhill

[ajhbike]

I haven't seen this talked about so I will ask the question.....
Mowing for the local Land Trust I may be tooling across town for 20 minutes or so in 4th gear. It is alot of up and down some mellow hills and I see that when I am going down hill and picks up speed due to momentum, the engine quiets but man o man it smokes blue smoke alot more than normal (I have some ring issues). It will continue with the blue smoke yet if I start going up hill and the governor kicks in, most of the smoking stops.

What causes more smoking going downhill and less going uphill?

I will say that I don't like faster downhill swaying back and forth in the spring seat.... Feels a little out of control. Normal 4th on a flat road is fine.

[Jim Becker]

The higher vacuum under closed throttle draws more oil in. This is frequently due to worn valve guides but more will get past the piston rings too.

[outdoors4evr]

Now I learned something new! Thanks Jim for the answer and ajhbike for asking the question!

[ajhbike]

Thanks....live with it or work on the engine guts...I guess I will have to some day.

[John *.?-!.* cub owner]

Does a super C use valve seals? If so it may help to replace them.

[Jim Becker]

Does a super C use valve seals? If so it may help to replace them.

Not originally. Umbrella style can be added.

[ajhbike]

John and Jim....valve seal replacement...is that a big deal for a non mechanic that can periodically follow instructions?

[Smokeycub]

John and Jim....valve seal replacement...is that a big deal for a non mechanic that can periodically follow instructions?

Well to start with you'd need to get umbrella valve stem seals that fit the valve stems, shouldn't be hard to find but as Jim said they weren't there originally. Then you need a spring compressor and a fitting to connect the air compressor via the spark plug holes. The compressed air will hold the valves up when the spring and retainers are off, doing one valve at a time. Since the C's 123 uses a rocker arm rail it will need to be removed and you''ll need to figure a way to use the spring compressor, usually done by removing the rocker arms. The retainers can be a bit tricky to get loose after 50 plus years, I've had to use a hammer and a socket on the retainer to free things up. After they're replaced the valves will need adjusted. I'm guessing your tractor smokes as well when restarted after being warmed up. It's very doable but a bit tricky -- and be sure not to drop a valve, if one drops in you will need to pull the head.

[ajhbike]

Oh boy. I will really need to plan this out. I will wait till the JD is here so I am not left without a field mower. Thanks Ray