Any way to test the old rectangle style fuel pumps? (Briggs & Stratton 42E707 2631E1)

[arkmail200]

If I spray starting fluid into the carb it will stay running, but wont start otherwise. I disconnected the incoming fuel line, and fuel flows freely by gravity, so fuel filter/lines are good. Prior to it stopping running, I was having to run it with almost full choke, so it seems it's a fuel issue.

I know the round fuel pumps with 3 fuel line connections, you can disconnect one hose and crank to see if fuel comes out, but I dont think you can do that with this one, can you? I'll start the process of buying a $10 rebuild kit, but was just curious if it could be tested somehow. I took it apart, and all the parts were intact, but I suppose the springs/rubber could be worn out.

I'm guessing carb could be an issue as well... I've cleaned/rebuilt quite a few of the basic unscrew the bowl carbs, but never one of these types that feed two cylinders. I'd rather not have to mess with the carb, but I guess if the fuel pump isn't the problem, I'll have to.

I guess one other thing could be bad gas, but I'm pretty sure any gas from last season has been depleted by now.

Thanks for any advice.

Briggs & Stratton 42E707 2631E1 9708015B

 

[Scrubcadet10]

Take the bowl drain bolt out and see if you have fuel in the carb. It's right next to where the choke cable is routed in.

 

[Born2Mow]

Take the bowl drain bolt out and see if you have fuel in the carb. It's right next to where the choke cable is routed in.

And as a second step, while the drain is out... do your spray starting routine. If more fuel comes out, then the pump is working.

 

[Forest#2]

If the pump is working per the above instructions you can with care remove the top off of that carb while it's still on the engine.
After the 4 screws come out of the top the gasket below has to come up with the top. I can 90% of time remove the top without ruining the gasket by using a thin putty knife or get it started coming loose with a box cutter blade.
Leave this area be if your pump IS NOT WORKING and jus twork on the pump.
Here is a link for repairing a 4 screw pump and carb. Just scroll down and select Briggs and Stratton opposed twin carb part 1, then 2.
The 4 screw pumps can usually be kitted in place but the 3 screw is more involved and needs removed from the engine and taken to the work bench so the itty bitty spring inside won't get lost, etc.
Usually just cleaning the bowl and blowing low pressure air (not over 25 lbs) through the air passages will get a run from the NLA carbs and no kit required if you can save the top gasket.
https://outdoorpowerinfo.com/repairs/

 

[slomo]

Pull the hose off AT the carb inlet. Drain into a glass jar.

 

[arkmail200]

Thanks for the input everyone.

Removed the drain plug and tried to start it, and fuel came out, so the fuel pump wasn't the problem. Removed top of carb and tried to remove the jet, but I guess you need a special tool. I sprayed carb cleaner into it, and it spurted out the top of the carb a little, then I put the red straw tube on the can into that passage, and it sprayed strong out of the jet the opposite way. Sprayed into the other passages a bit, and ran a small wire in and out where I could. Put the top of the carb back on, and it ran great.

Or at least it did for about 30 minutes until 2 of the spindle bolt junctions rusted through and dropped the blade into the ground, ugh. Luckily it was only small breaks in the deck, and the rest of the rim was in good shape, so I just rotated the spindle, drilled 3 new holes, and then used bolts with nuts to give it more holding power.

Runs real strong now. Only issue is that the throttle doesn't do anything, so I will have to look at that some point. It runs a little fast with no load, so I just use the choke like a throttle and give it a little a choke to slow it down until I engage the blades. Been a long time since I messed with a throttle/governor, but the part that moves doesn't hit the little rod that sticks out, and I think it's supposed to, right?

Thanks again.

 

[slomo]

Removed top of carb and tried to remove the jet, but I guess you need a special tool.

You need gunsmith flat blade screwdrivers. As in chisel ground or parallel ground flat blades with the sides ground off to fit in the hole where the main jet is. The blade needs to fit the main jet slot perfectly and tightly. And the sides ground off as not to foul up the threads for the main jet and emulsion tube.

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[Forest#2]

What is your latest question?

 

[slomo]

He has a throttle cable issue I think.

 

[arkmail200]

What is your latest question?

The throttle control doesn't do anything. When I move the throttle up and down, the triangle plate in the picture moves, but never touches the rod sticking out, which I'm assuming is the end of the governor. Is the plate supposed to make contact with that rod, and if so, how do I adjust it properly?