TO35 idle speed

Bruce95304

New User
The books all call for a 450 rpm idle on the TO35 (mine's a 1959 model) but I can't keep it running that slowly. Like most of my equipment (cars, tractors), my TO35 seems quite content to purr along at 600 rpm without skipping a beat. At what idle speed do the rest of you use on a TO35 (gas, Z134)?
 
Howdy California. 400 RPM is attainable if you have no problems with any components of the engine. Timing is what? I currently have two
machines needing attention to get them down. A higher idle speed just tends to put more wear and tear on the clutch disc. Higher idle speed
will also give cleaner emissions and once California needs smog tests done on tractors, you might pass with a higher idle.
No?
 
When you say you can't keep it running that slow...

Do you mean it tries to die when you adjust it any slower?

Or it refuses to idle any slower when the idle stop is backed off?

Getting it to idle down is easier on the transmission when shifting, but otherwise there is not a lot of reason to get it to idle down. Kinda your choice weather to pursue it.
 
Hello, my to35 idles at 400 sweet, with
electronic ignition and hot Autolite
plugs... mine always had a flutter to it
and when it had points in it....Ed
 
It's been a few weeks but I recall the engine just can't keep running and wants to die when I try to lower the RPM. When I do go to shift into gear, I hold the clutch down for a at least 5 seconds before slipping into gear. After selecting a gear, I then select H or L. I rarely get any grinding using that procedure.
 
Remove the dist cap and twist the rotor, does it move? Does it return to the original position or just "close"?
If it snaps back then the advance is working, if it drags back it is gummed up, if it does not return, it is really gummed up and needs disassembly and cleaning.
Point gap and condition (burnt? angled?) inside the dist will effect timing. Check that and make sure it is correct. 80% that is NOT your problem but you start at the beginning. Timing at the higher RPM is also checking the mechanical advance inside the distributor. If your checking the base timing at too high an RPM, the mechanical advance is also kicking in and advancing it a bit for you. If your running at 600 RPM, I do NOT believe the mechanical advance is working at that speed.
It is also possible to have a slight vacuum leak at the manifold but if your machine is running at 600 RPM, I would nearly have to discount that. Backyard checking for a vacuum leak would entail using a can of carb clean and very slowly pushing down and lightly on the nozzle until the fluid just barely spurts out the end of the can. This takes practice. I have also found when using carb cleaner around spark plugs on a running engine, it is also advisable to keep a charged garden hose handy. Tractors generally is not a problem as you are far enough away from an ignition source.
That takes you into the carb itself and at 600 RPM, I doubt the filters are plugged. if they were, you would have fuel flow at a low RPM but not a higher RPM. So if it's running at 600, it would run at 400. This takes you into the fuel adjustment screw and I believe on that carb, turning it in adds fuel to the engine, turn out adds air into the mix.
If someone in the past has cranked that screw in hard, I mean beyond finger tight, chances are the needle and seat are damaged.
Re move the needle, is it bent? Grooved?
A good quality carb rebuild kit will have that adj screw in it, but might not have the seat. I have seen one or two kits that have the seat. Look at the higher priced kits to find those.
Your now chasing 200 RPM which means that everything needs to be in prime condition. A paint job is not going to make it run.
If your running crystal smooth at 600, GENERALLY then it is a balancing game of carb air and idle to bring it down. if it flutters out and dies, double check that timing.
We'll see you again next week for another exciting episode of "Counter-Top Diagnostics" Thank you and good night.

PS. Counter-Top Diagnostics is done with a crystal ball. Unfortunately the batteries are dead.
 
First, some back story on my Fergie:
She spent the past twenty years sitting outside, not running at all, due to "mechanical problems". I needed a small utility tractor and my cousin gladly gave it to me just to be rid of it. Other than having a couple of gallons of rainwater in the transmission (failed shifter boots), it wasn't in too bad of condition. I pulled the transmission cover plates and cleaned out a few decades of debris, buttoning it up with some fresh oil.

I have replaced several entire systems just to get a fresh start: ignition, carburetor, fuel shutoff/screen, and fuel lines. I also cleaned out everything in sight: fuel tanks, induction system, power steering. I rewired the ignition system as the previous "mechanic" had the ignition coil attached to the ACCessory contact of the ignition/starter switch (no wonder it didn't run!).

For induction systems leaks, I generally use an unlit propane torch to find any leaks. I should do that just to make sure I didn't miss anything. As for the carburetor idel adjustment, I just set it intentionally lean (screw out) and use a little pull of the choke to tell me how much more I need to screw in the idle air adjustment. As I mentioned, it's idling with a very steady purr right now -- at 600 rpm. I'll slowly try some lower idle speeds to see how well it fares.

And paint -- it is what it is. You can't get that perfect patina out of any paint shop.

Thanks for your comments.
 
Your on the right track. Too bad you can't quite use the GM lean drop method to adjust your carb. Sounds like your just going to have to run a balance test of a bit less idle screw and a bit more air mix screw. The carb being replaced, was that a new aftermarket carb or a rebuilt original?
The last machine I picked up was an 8N that had been sitting 20 plus years with mechanical problems. I have it running but it has more problems and I have not had time to play with it.
 

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