any small engine guru's here?

[lewtot184]

my riding mower engine quit and has me stumped. it's a simplicity with 21hp B&S single cylinder. the engine has a pulse fuel pump but won't pump fuel. put a new pump on and it still won't pump fuel. i've run out of ideas here. anybody know anything about these engines and what would prevent the pump from working?

 

[Gpuller]

Is the rubber hose connects the pump to the crankcase good? Fuel filter plugged?
Is there gas in the tank? LOL

 

[SteveSS]

I got mine out this summer and it went clatter, clatter, bang. Threw the piston out of the crankcase.

 

[lewtot184]

Is the rubber hose connects the pump to the crankcase good? Fuel filter plugged?
Is there gas in the tank? LOL

i pulled the fill tube washed it and the hose out and there wasn't any obstructions. new screen type filter and all connections are in their correct location. weird! as long as i put fuel in the air inlet of the carb the engine will run.

 

[lewtot184]

I got mine out this summer and it went clatter, clatter, bang. Threw the piston out of the crankcase.

i don't think this heap has enough power to toss a piston.

 

[MarPar]

did you bench test the fuel pumps to make sure they work?

 

[super-bee_ski]

Hi Lew
I look to guys like you for technical help!
But I can tell you this:
I have a 26 or 28HP Husquavarna 56" deck
Twin Briggs
And always, every year I get a fuel blockage due to the California gasoline eating up the rubber seals and hose
I creates a blockage
It also eats the diaphragm

 

[lewtot184]

did you bench test the fuel pumps to make sure they work?

how would one bench test this type of pump?

 

[MarPar]

ask, and ye shall relieve...

 

[Cranky]

Will it fire off if you manually fill the carb or give it a shot of starting fliud? The pulse pump on my garden tractor never seems to pump when I disconnect the down stream hose (should it?) but it's been running since 88. Also, just because it's new doesn't mean it's going to work but if you can get it to fire off, that may be all it needs. Mine will do that from time to time and especially so if it sits for a few weeks which happens sometimes . A quick shot at the air cleaner with some starting fluid usually gets the ball rolling again.

 

[lewtot184]

Will it fire off if you manually fill the carb or give it a shot of starting fliud? The pulse pump on my garden tractor never seems to pump when I disconnect the down stream hose (should it?) but it's been running since 88. Also, just because it's new doesn't mean it's going to work but if you can get it to fire off, that may be all it needs. Mine will do that from time to time and especially so if it sits for a few weeks which happens sometimes . A quick shot at the air cleaner with some starting fluid usually gets the ball rolling again.

engine will run as long as i can shoot some gas in the carb inlet. when that fuel is burned the engine quits.

 

[lewtot184]

ask, and ye shall relieve...

good info. unfortunately i can't check fuel line flow from the tank to the pump because of the position of the supply line on top of the tank; simply stated, no gravity feed. i did run a pump inlet line directly into a 5 gallon gas tank (eliminating the tank to pump line) and it still won't pump fuel. thanks for your help!

 

[garrett1308]

I'd check to make sure you have crank case pressure to operate the pump, you might just be missing a valve cover gasket.

What brand of pump did you get?

 

[khryslerkid]

I'm sure you have one of these laying around...

 

[PRND21]

good info. unfortunately i can't check fuel line flow from the tank to the pump because of the position of the supply line on top of the tank; simply stated, no gravity feed. i did run a pump inlet line directly into a 5 gallon gas tank (eliminating the tank to pump line) and it still won't pump fuel. thanks for your help!

So, you've got fuel at the pump inlet? A little air pressure in the tank to prime the pump is sometimes needed. The Briggs engines I've ever had trouble with usually had a little varnish build up in the carb not letting fuel flow, but I'm sure no expert on these engines. Good luck.

 

[Gpuller]

i pulled the fill tube washed it and the hose out and there wasn't any obstructions. new screen type filter and all connections are in their correct location. weird! as long as i put fuel in the air inlet of the carb the engine will run.

Check the pulse line to see if it dosent have a pin hole or something like that. If there is a hole in that hose it won't hold pressure or vacuum. Maybe the new pump is no good

 

[lewtot184]

So, you've got fuel at the pump inlet? A little air pressure in the tank to prime the pump is sometimes needed. The Briggs engines I've ever had trouble with usually had a little varnish build up in the carb not letting fuel flow, but I'm sure no expert on these engines. Good luck.

took the carb apart, again (ugh!), needle is sticking and won't drop. tried loosening it up but the viton stays stuck in the inlet hole. i'm thinking i've got a couple of issues going on. the pumps don't provide any pressure so it's not going to knock the needle off the seat. crankcase pulses may be an issue if the engines going south (maybe 100hrs on the engine, but it's a B&S so maybe it should've took a dump at 100 minutes).

 

[lewtot184]

I'm sure you have one of these laying around...

View attachment 358525

i know your funning but i thought about some very low pressure electric on a switch vs $2500-$3500 for a new mower.

 

[lewtot184]

i wonder if goats are cheaper than lawn mowers? think i'm going to take my '65 dodge out on a 100 mile cruise in a few minutes and forget about this thing.

 

[Gpuller]

Give a neighbor kid to mow it for $20.