8N Idle Speed

I have an 8N with front mount distributor and no proof meter. I adjusted the carburetor with throttle at lowest position following these instructions:

[b:c15c79c0b4]"Make sure the tractor is at operating temp; that usually takes 10 15 minutes at idle depending on ambient temp.

Both Ford and Marvel/Schebler (assuming you have a M/S carb ) say to set both the side-pointing idlemix and the down-pointing mainjet to 1-turn as a starting
point. I set the down-pointing mainjet to 1-1/2 turns and don't fool w/ it until the final step.

Then adjust the side-pointing idlemix for fastest idle; not the smoothest idle. Next, adjust the behind the carb idle-speed set-screw for very slow 400-rpms
idle. Do that idlemix adjust for maximum idle at least 3-times. Make sure that you turn the screws slowly, like 1/8 of a turn at a time & wait a second or two
for the engine to catch up. Take your time!

Do it like this:

1. Adjust idle mix jet until RPM increases

2. Adjust idle-mix set screw until the engine nearly stops (as slow as you can get it unless you have a tach that tells you 400 rpm)

Repeat steps 1 - 3 three times.

Remember the side-pointing idle mix is out for lean, in for rich.

If you do not have any problems inside the carb, it is easy to get the idle down to 350 - 400 rpms.

Your last step is to go back to the main jet. Remember, in for lean, out for rich. If you end up turning it OUT more than turn for max power (remember, you already had it 1 turns out) then stop right there because you have a dirty carb or a fuel problem."[/b:c15c79c0b4]

Although I have a nice slow idle with the throttle at slowest position, I have no throttle response for the first 1/4 of throttle opening. What should I do next?

Adjust the rod going to governor!

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This post was edited by Smokeonthewater on 08/07/2021 at 12:50 pm.

The lever at the bottom of the rod from the throttle lever (above the toe of your right shoe when seated) is adjustable.

Thank you. That's what I was wondering. Is it logical that I need to shorten the throttle to governor rod?

This post was edited by Papillon on 08/07/2021 at 03:07 pm.

If your oil pump is old and worn out like mine. Keep an eye on your oil pressure, especially with a hot engine. My engine idles great at 350RPM but with a hot engine the oil pressure will drop to zero. Oil pump rebuild is on the list for a future project.

(quoted from post at 15:01:42 08/07/21) Thank you. That's what I was wondering. Is it logical that I need to shorten the throttle to governor rod?

This post was edited by Papillon on 08/07/2021 at 03:07 pm.

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Yes, I say shorten it, but you might want to check the governor spring adjustment first. One of mine does the same as yours. I was watching it yesterday and if I was concerned about it I might adjust gov Spring first. the spring should have no end play at all. That said it really does not brother me at all. Watch the gov arm when you are slowly increasing the throttle. go from there.

Thank you. I will look at the spring first. Is it easier to do that by taking the governor off the tractor?

(quoted from post at 12:02:08 08/08/21)
Thank you. I will look at the spring first. Is it easier to do that by taking the governor off the tractor?

Click to expand...

do not know, let us know! mine is a bit too loose!

This post was edited by kossuth on 08/08/2021 at 02:50 pm.

I'm guessing you overlooked my post above. You do not need to shorten the rod, you need to adjust the lever at the bottom of the throttle lever's rod