Small engine with points?

[CalG]

No longer than it takes I pulled the head. Neither valve will spin when fully closed. I liked that idea but I don’t think that’s it.

I should also add that there is a small chamber under the short intake tube under the carb. That chamber is filling with gas on its own.

That is what the diaphragm you replaced is meant to do!

The carb sucks from that little chamber,
The diaphragm pump pulls from the main tank and keeps that small chamber filled.

You have eliminated a lot of potential problems. Next is to get that fuel up into the carb on it's own!

You can do this! ;-)

 

[CalG]

The valves appear to be sealing enough to not cause major issues. And that small well is supposed to fill with fuel. Basically the fuel pump diaphragm pumps the fuel from the tank into that well, and then vacuum created in the carb venturi caused fuel to flow up the short tube into the carb intake. Basically atmospheric pressure will only lift fuel something like 1-3/4 inch. Since the vacuum created can't lift fuel from the lower level of the tank.

Just to be science-terriffic-er, Atmospheric pressure will lift water EXACTLY 14.7 FEET (STP conditions)
Gasoline being lighter than water, can be pushed even higher.
Added science, 14.7 feet of water is equal in weight to 760 mm of Hg.

But that is all useless information for these purposes.
(Even though I did once suck all the Mercury from a four barrel carburetor balancing manometer when I rolled off the throttle....;-)

If you can't dazzle 'em with dribble, baffle 'em with BS! ;-)

 

[dodge man]

Unless by some miracle it starts on its own in the next couple of days it’s not getting fixed. The tiller will be repowered.

 

[CalG]

You are going to miss that reverser!....

Well, not you, but it will be missed. I use it every time I till.

 

[CalG]

Too bad you are in "fly over country", we could tag team this sucker and have it purring in a couple of beers (ahh,... err Hours ;_)

 

[ultrarunner]

I’ve got the pony and no complaints… the reverser is a nice feature.

I did loan it to my brother’s brother in law and he tied it down with string…

Got it back with a busted off carburetor from summersalts in the back of his pickup.

I’ve got a few more loaning out stories but it would be off topic…

The horse would have been too gig and the pony was just right.

 

[RandyT]

Just to be science-terriffic-er, Atmospheric pressure will lift water EXACTLY 14.7 FEET (STP conditions)

In a perfect vacuum. And the inlet low pressure area created by the inrush of air isn't close to a perfect vacuum. And that fuel lift distance wasn't my idea that came from Briggs. If the 14.7 feet was true in this case they wouldn't need the small well to deposit fuel to be drawn into the intake.

 

[CalG]

Call it a "pony Story" a bit off topic , but....

We have been living at this place for over 35 years now, gardening all the while, adding all the time. The Troy Built Pony our only mechanized "garden" tool except for the ripper I built to pull behind the Bolens for breaking into new gound.

We recently got a hankering for more asparagus, so I dug a couple of trenches in a well established garden bed.
Wouldn't you know, at a depth "just about the maximum of the tiller" I hit the grayest, sandiest, clay one could EVER not want to be garden loam.

Call it "Pony Depth" ;-)

The wife was digging deep holes for something else in one of the other garden spots (we have four , to spread the losses when the deer come through ;-)

She hit the same stuff!
Call it "Pony Depth"


Not sure if it matters for 99% of garden plants, but it is interesting.

We have added so much "tilth" to the top foot of soil, we are surprised by what is just below.

 

[CalG]

In a perfect vacuum. And the inlet low pressure area created by the inrush of air isn't close to a perfect vacuum. And that fuel lift distance wasn't my idea that came from Briggs. If the 14.7 feet was true in this case they wouldn't need the small well to deposit fuel to be drawn into the intake.

Gosh, You kicked me into reason.

What was I THINKING? NOT!!!

14 .7 is the PRESSURE in pounds exerted by the air column above us (at sea level.

The resulting Column of LIFT available from that pressure is closer to 34 FEET!

My bad! Sorry for the confusion.

Even at idle, an IC engine can produce 20 inches of Hg of vacuum.

That would lift about a foot of gasoline no problem.

 

[dodge man]

I got the old engine off. Waiting for him to show with the new engine.

 

[CalG]

Too bad it's so costly to ship anything even that heavy. Crating and boxing etc. It's just not worth it.

But on a lark, I would challenge myself to get that engine running again.

But NO! What am I thinking? I've got stuff enough to do!

I had to replace the fuel lines on the weed trimmer today. Darn thing just quit while whacking, with lots of fuel in the tank.

For the life of me, I can't say why I focused on the fuel line right off, The old stuff came out of the tank in several pieces .....Usually I would tear into the carb....

A quick motor bike ride into town to purchase some new fuel line, and back at it. ;_)
Might have chopped up some poison ivy.... ah-oh!

 

[dodge man]

We got the predator installed. We got a new belt and it was to tight and we couldn’t start it. We finally figured out we had the pulley installed wrong. It has a two pulley system so you can vary the ground speed. With the pulley on backwards the belt was far too tight. Once we corrected that it started on the first pull. The belt is still a touch too tight so the tines won’t quite go into neutral. Hopefully it will stretch a little and get better. I forgot to get a picture though.

 

[2manyrocks]

Were you able to install the Predator in a way to get the reverser to work?

 

[gstrom99]

You can use a match book cover to set the points the match
book covers were used to set points in cars and trucks back
in the days
Don't forget to change the capacitor/condenser when it gets
hot you will have problems

willy

Match books are as rare now, as points.

 

[dodge man]

Were you able to install the Predator in a way to get the reverser to work?

No reverse now.

 

[2manyrocks]

So DJ54 had it right when he posted that the reverse pulley is tied into the engine crankshaft to power the reverse. Is that right?

 

[dodge man]

So DJ54 had it right when he posted that the reverse pulley is tied into the engine crankshaft to power the reverse. Is that right?

Sort of. I think it’s actually powered from the camshaft. There are two shafts coming out of the engine, the normal one that is the crankshaft, then a second one that someone posted is an extension of the cam shaft. I haven’t taken it apart to verify that but it sure looks to be the case.

 

[RandyT]

Sort of. I think it’s actually powered from the camshaft. There are two shafts coming out of the engine, the normal one that is the crankshaft, then a second one that someone posted is an extension of the cam shaft. I haven’t taken it apart to verify that but it sure looks to be the case.

I can confirm it is a camshaft extension to operate reverse. Was common on older tillers to have either the extended camshaft or to use the main crank pulley but twist the reverse belt into a figure 8

 

[2manyrocks]

Thank you for explaining that. I've always been curious how reverse mechanisms work on machines that only have belt drive via pulleys and not a geared transmission with a reverse gear.

One of the later David Bradley two wheel tractors sold by Sears had a reverse pulley arrangement plus a variable speed via a pulley as well. Wish I had photographed it better when I had one, because I've always been amazed that it worked.

 

[RandyT]

Thank you for explaining that. I've always been curious how reverse mechanisms work on machines that only have belt drive via pulleys and not a geared transmission with a reverse gear.

One of the later David Bradley two wheel tractors sold by Sears had a reverse pulley arrangement plus a variable speed via a pulley as well. Wish I had photographed it better when I had one, because I've always been amazed that it worked.

Some of the newer units will roll the belt with the groove facing out. And run the reverse belt off of an idler pulley sitting above and to the right side of the crankshaft pulley that makes contact with the right side of the crankshaft pulley when the belt is tensioned, basically causing the belt to turn the opposite direction.