What was the previous owner thinking?

[Spike188]

The 446 was chosen for mowing duty this afternoon. It joined the pack a number of years ago. It has always been hard to start. The only way to get it started is by pulling the air cleaner and nursing it with a bottle. The Onan will eventually burp, belch, spin then burp and belch some more. I have never seen an Onan be as stubborn when it came to needing priming and coersing
before settling into a purr.

A couple of weeks ago, my thought was, it needed a new fuil line, or maybe has a plugged filter

I even wondered if the fuel pump is bad. That is when I learned that if a 446 will start, it has enough vacuum to draw fuel from the tank, minus a pump, and will run well enough to mow with.

The previous owner said it was very hard to start. That was an understatement. Why did he get rid of the pump?

[Timj]

Well, I guess if you add a primer bulb you'll be good to go.

[keith]

That's exactly what I did for a craftsman tractor. The vacuum pump would not draw gas if the tractor sat for long periods of time, a couple of squeezes of the primer bulb and it would fire right up.

[Eugen]

Well, I guess if you add a primer bulb you'll be good to go.

Brilliant! We all know fuel pumps are for perfectionists!

@Spike188 , in all seriousness, while annoying to find the fuel pump missing, this is the kind of story that's worth telling at tractor meets.

[Eugen]

That's exactly what I did for a craftsman tractor. The vacuum pump would not draw gas if the tractor sat for long periods of time, a couple of squeezes of the primer bulb and it would fire right up.

Did you install it in a handy location to give a couple of nitro squeezes when going uphill?

[keith]

Eugen, the fuel line ran to the outside of the engine exposed on the side so nothing had to be opened to or moved.

[Timj]

That's exactly what I did for a craftsman tractor. The vacuum pump would not draw gas if the tractor sat for long periods of time, a couple of squeezes of the primer bulb and it would fire right up.

I haven't seen any lately but have seen primer bulb on quite a few Case's. Assuming for the same reason.

[Spike188]

Some owners have replaced the vacuum pumps with electric. The RPM drops off and never recovers when the deck is engaged. In tall grass the rpm does remain steady. Is the rpm drop a factor due to the lack of a fuel pump? One way to find out would be to add a fuel pump to the system. @Harry did you add an electric pump to one of your tractors and if so what did you use?

[Harry]

Some owners have replaced the vacuum pumps with electric. The RPM drops off and never recovers when the deck is engaged. In tall grass the rpm does remain steady. Is the rpm drop a factor due to the lack of a fuel pump? One way to find out would be to add a fuel pump to the system. @Harry did you add an electric pump to one of your tractors and if so what did you use?

I used a Facet electric pump. It worked flawlessly on my 446 snowblower GT, until it didn’t. I’m not sure why but went back to the pulse pump. I like the idea if a pulse pump which I would use on a Kohler powered 644 lbh. Someone on here recommended a small hole in the air cleaner cover, and give it a shot if starting fluid before starting. That works great, but I try the primer bulb idea. Harry

[keith]

Another idea is to drill a small hole in the throat of the carb for a for a small fitting, connect a gas line primer push knob in the dash and connect them to the main gas line. A couple of pushes and you' are good to go. This is from an old ski-doo engine. This setup was what I was going to use on the craftsman but went with the primer bulb because the gas line was a good spot.