Small engine with points?

[CalG]

Well!

I dug the Troy Built Pony tiller out of the back corner of the tiny garden shed. Took all of four minutes to move the lawn mower, the wheel barrow, a couple of pots and a few half empty bags of potting soil.
Dragging the machine out the door was a bit more work.
The machine hasn't been out of that location since a year ago summer, so two full winters till today.

I checked the fuel level in the tank, about half full, (Did I put it away full? IDR) Said "Good to GO"
Pulled the choke,and set the throttle.

Gave it two half hearted pulls to get the fuel up and around, The engine started on the third pull. Thick running with the choke pulled, I pushed that back in. The engine came right up to speed. Throttled back, and it just purred along.
Exercised the controls, pulled the knob to be sure the drive worked bout forward and revers. Drove it over to the garden and tilled a couple of ten foot passes. (Most of the garden is already planted, and my wife gets all concerned when I'm out there with power equipment ;-)
Worked a treat.

I shut it down, emptied the lion's share of the fuel tank contents, and then started the engine again to let it run till it went dry. That took quite a long while fortunately, I feel the engine oil got "dried out".

Now I'm wondering if I should put the tiller away again with an empty fuel tank? It's always been my habit to store engines with FULL tanks to stop condensation. My favored method is to store fuel tanks with a fill of two stroke mix.

What do you think?

Seems to be a great little tiller. It was my wife's fathers. He had it for many years, we have had it for more than 35 years. It was used a lot in the early years establishing the gardens, But not so much any more.

We are sort of in the "no-till" mode, just using mulch and a small amount of fork or rake work just when planting

Oh, This is definately a points and condenser ignition, I've had the flywheel off many times over the years to clean the points.

 

[dodge man]

I give up, I keep tearing into it deeper and just can’t find why it won’t run. I think it carb related but I still can’t make it run. I ran it on starting fluid but it won’t run on its own.

 

[CalG]

No head and no flywheel, no wonder it won't run! ;-)

When confronted with symptoms like you have, I put some gasoline in a squirt bottle , expose the carb air inlet, and see if I can get it to run and stay running "on the drip".

That separates the "Is it fuel, or is it ignition" question. Always check for spark as soon as the flywheel goes back on. A strand of lint in the points, and the spark is no-go.

Everything looks so clean, it's got to be something small.

I assume you pulled the fuel tank off the carb body to make sure the lift tube is intact.

 

[dodge man]

Not exaggerating, I’ve had the carb off 10 times. It will run with gas in the carb or starting fluid.

 

[ultrarunner]

Has to be fuel supply…

Had a gas engine with a pinhole in the fuel system that would let air in.

Had another where the gas cap vent was obstructed…

It was giving my friend fits and I told him try running with the cap off… he did, it ran and from then called me the engine whisperer…

His solution was to drill a hole in the middle of the cap… would not have been my first thought.

 

[2manyrocks]

Take a step back from it. Nothing goes right when you are frustrated. Give yourself a break.

 

[1Mech]

Sometimes best to repower with a HF predator instead of chasing diagnosis and old parts.

I did that very thing on an old Horse Troy Bilt. Had to add weight to the front to keep the tiller from jumping forward while tilling. The Harbor Freight clone is an aluminum case, the original Kohler was a heavy cast iron engine. It ran great with the clone, until I dug in and angled it down, then the low oil sensor kicked in, shutting it down. Had to run with the crankcase over full to keep it running. I built a box to hold lots of ballast to make up for the lost weight. My grand daughter used to like to ride in the box when I tilled, live ballast!
The clone setup had no reverse since the extra shaft was missing.

 

[dodge man]

I tried the gas cap thing.

Just a little back story. This tiller was made in 1981 and the original owner used it some and then it sat unused for roughly 25 years. It was given to my buddy roughly 5 years ago. I got the thing running 5 years ago by just cleaning the carb. My buddy lined the gas tank. This last year he let it sit all winter with about half a tank of e10 gas.

That brings us up to date with this thread. In a couple of days he plans on getting a predator engine for it.

 

[2manyrocks]

If he hadnt run ethanol, that tiller would still be running, IMPO. I suspect the carb isnt creating the vaccum needed to draw gas from the tank below and/or the pickup fuel assembly is somehow messed up.

I ran my Troy Bilt horse with the newly installed HF greyhound engine this week. Easy starting and much more quiet. Also lighter.

I would install the Predator to get the tiller going, but would keep the Briggs to revisit later to see if that carb and pickup assembly can be made operational again.

One thing I like about the Pony is it is big enough to do some real tilling, but small enough to get between rows as plants begin to mature. They are good tillers.

 

[RandyT]

I give up, I keep tearing into it deeper and just can’t find why it won’t run. I think it carb related but I still can’t make it run. I ran it on starting fluid but it won’t run on its own.
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Since the intake valve is open put your thumb on top of the exhaust valve and see if it turns. And then turn the engine over to close the exhaust valve and then try to turn the intake valve. I will bet one or both will turn with just thumb or finger pressure, which means the valves are not sealing and you are loosing compression. Have worked on 3 in the past 2 weeks with this issue.

 

[rgr33]

Your experience is similar to what I went through with a free to me Troybilt tiller Hard to start, and sickly when running. Fussed with it for 3 summers.

Over the winter, I noticed Harbor Freight had a good sale price on the Predator motors.
I bought one, super easy to install, and curse myself for all the crap I went through with the original motor.
Much happier now

 

[2manyrocks]

Other than having to replace belts, the tillers themselves are usually trouble free. They used control rods instead of cables to engage the drive. The tines were made of quality metal. Never imaged I would see the day when these old kohlers and briggs would be replaced with chondas.

 

[dfkrug]

...the valves are not sealing and you are loosing compression.

This is one of the reasons I have never been a fan of the old flatheads. To get some clearance for the valves to seal, the OP will have to grind a bit off the ends of the valves.

I much prefer the OHV engines, where valve clearance is super easy to check and adjust. But these adjustments are needed way more often.

Now, back to my 2002 vintage flathead Tecumseh project...

 

[CalG]

I have to ask, how does an engine that starts and runs on "direct injection" of gasoline have a valve problem?

I find it VERY difficult to blame the valve lash for an engine that starts.

If it ran for long enough time to heat the valves, lengthening the stems, that would be different.

 

[dodge man]

In the port behind where the pcv valve is you can see where the valve and a lifter meet at the valve spring. I was able to fit a feeler gauge in between. I don’t think the valves are being held open but it is possible they aren’t sealing.

Another thing I’ll add. It was making oil. There was an air leak between the tank and carb and I think this was making it run rich for the brief seconds it would run. The plug would always look wet. With the air leak fixed it seems like the plug is dry now. I just don’t think it’s getting fuel.

 

[2manyrocks]

With it running when you pour fuel into the carb, it looks like a fuel delivery problem. Could be some residual rust blockage or the ethanol has caused something to loose its ability to seal so the diaphram cant quite deliver enough pressure to lift gas out of the tank.

 

[RandyT]

I have to ask, how does an engine that starts and runs on "direct injection" of gasoline have a valve problem?

I find it VERY difficult to blame the valve lash for an engine that starts.

If it ran for long enough time to heat the valves, lengthening the stems, that would be different.

Sometimes it isn't a valve lash issue. Sometimes the valve face wears to the point the surfaced don't make contact. Just worked on a Briggs 90102 a couple of weeks ago that had .005 IN and .007 Ex without touching the valves. Engine had 0 compression with a 80% bypass with leakdown tester. Found that both valves could be turned by the finger test.. After removing the carb/tank assembly could shine a light into the intake and see light around the intake valve.

That job required the use of my Neway valve face cutter and also the Neway valve seat cutter sets. And still had to hand lap the valves with grinding compound to get them to seat properly.

Symptoms of this engine was it would start on the first pull with choke but wouldn't rev up or continue to run even with full choke, but would pop off immediately on restart and do the same thing. The added fuel would create enough seal to ignite the fuel, but couldn't continue to build compression to continue to run.

 

[dodge man]

We had a decent lawnmower place that worked on small engines also. My friend that owns this tiller called him and also talked about a valve problem with it. At this point nothing would surprise me. I never actually kept it running by slowly pouring fuel in the carb, just got it started that way and then it died. I did keep it running on starting fluid though. It’s pretty volatile though so it would probably run on it even with a valve problem.

 

[dodge man]

Since the intake valve is open put your thumb on top of the exhaust valve and see if it turns. And then turn the engine over to close the exhaust valve and then try to turn the intake valve. I will bet one or both will turn with just thumb or finger pressure, which means the valves are not sealing and you are loosing compression. Have worked on 3 in the past 2 weeks with this issue.

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.

 

[RandyT]

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.

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.