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Good spark and new spark plug
New mechanical fuel pump
Fuel flows from tank to fuel pump but when I crank no fuel from pump to carb bowl.
Carb solenoid tested and works fine (retracts when key engaged when I ground it)
Cleaned carb thoroughly. Still no fuel.

One thing I noticed is one of the fuel pump mounting bolt holes is stripped so I’m not getting a good seal. Is it as simple as Helicoil the bolt hole and tightening the mounting bolts to spec?

Thanks. First post but I’ve learned a lot on this site. Tom

double check the connections to the pump.
It has 2 one way valves so if it is backwards it can not pump.
Usually there will be an arrow or marked "in" & "out"
Take it back off and stick your tounge over the holes one at a time while working the pump to check it is working ( yum)

bertsmobile1 said:

double check the connections to the pump.
It has 2 one way valves so if it is backwards it can not pump.
Usually there will be an arrow or marked "in" & "out"
Take it back off and stick your tounge over the holes one at a time while working the pump to check it is working ( yum)

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Aw shucks. I’ve never made out with a pump. ? Thx for the idea. I will test the new pump to make sure it is pumping. I do have it mounted with the arrows pointing toward carb.

Since it is a mechanical pump I assume the lack of seal between the pump and mount wouldn’t affect the function of the pump. The eccentric lobe would actuate the lever regardless of the stripped mounting bolt hole not allowing a tight seal? I’m guessing that’s how the kohler pump works. ? Thx. Tom

Yup, a diaphragm , a spring & an eccentric not much to them.
Most people change them for an impulse pump on anything other than a fuel injected engine
Just put a block off plate over the hole then fit a nipple on the dip stick tube is the easiest way to do it.
Some times a new pump will have a bung in the holes and not to mention names I do know a tech who was having a chat and screwed the pipes into the pump while leaving the bung in there.

bertsmobile1 said:

Yup, a diaphragm , a spring & an eccentric not much to them.
Most people change them for an impulse pump on anything other than a fuel injected engine
Just put a block off plate over the hole then fit a nipple on the dip stick tube is the easiest way to do it.
Some times a new pump will have a bung in the holes and not to mention names I do know a tech who was having a chat and screwed the pipes into the pump while leaving the bung in there.

Click to expand...

Pulled pump off. Manually actuated the lever and air sucks in the inlet and it pushes air out of outlet. I connected to the fuel line And manually actuated it and it spurted fuel out of the outlet.

I’m wondering if the eccentric isn’t hitting the lever. I’m perplexed. Thx. Tom

That is all that is left.
No idea if there is a long & short pump but could be the eccentric is worn past it's service limit.

bertsmobile1 said:

That is all that is left.
No idea if there is a long & short pump but could be the eccentric is worn past it's service limit.

Click to expand...

I’m going to try to judiciously bend the lever to see if I get any love. If no fuel I’m going to follow your suggestion to switch to a Briggs style pulse pump. Either off the oil tube with a barb or I’m wondering if I take the innards and lever out of the mechanical pump if I can get pulse from one of the existing barbs and plug the other one. Thx for your help. Tom

Ooooh , that is a cleaver idea.
Never thought of gutting the old deceased pump

bertsmobile1 said:

Ooooh , that is a cleaver idea.
Never thought of gutting the old deceased pump

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Taryl video on using the housing to connect the Briggs style pump. I ain’t that clever. I bent the actuator lever just a tad. The mower started but it took some time. It’s never been a great cold starter but it seemed to take longer to start. Mowed half hour. Shut it off and then it wouldn’t start. Next day it started with some patience. Then I shut it off and it wouldn’t start again. I need to test the fuel flow now that the pump is working. Maybe I need to bend more to contact the eccentric.

Alternatively I’m wondering if it could be the coil. It’s a bit of a chore to get to the coil but perhaps the coil is affected by the heat? Or maybe I’m making up stuff in my fragile little mind. In any event, I’m going to check the various switches and sensors. And hopefully get this tractor back to work. Thx. Tom

Easiest way to check the coil is to fit a pair of red spark testers to the plugs then go mow.
When the engine refuses to start have a look at the testers.
If they are flashing the coils are good/
A couple of customers who are into show cars ended up fitting flashing plug caps which of course do the same thing.

ALthough my first thoughts would be heat expanding the pump housing just enough to prevent the pump working properly.
You might be able to fit a rubbing block on the end of the pump lever rather than bending it more.

bertsmobile1 said:

Easiest way to check the coil is to fit a pair of red spark testers to the plugs then go mow.
When the engine refuses to start have a look at the testers.
If they are flashing the coils are good/
A couple of customers who are into show cars ended up fitting flashing plug caps which of course do the same thing.

ALthough my first thoughts would be heat expanding the pump housing just enough to prevent the pump working properly.
You might be able to fit a rubbing block on the end of the pump lever rather than bending it more.

Click to expand...

What’s the red spark tester? It’s a single cylinder so by plug it connects in line and lights up if there’s spark? Or? Thx.

Tannersnoo said:

What’s the red spark tester? It’s a single cylinder so by plug it connects in line and lights up if there’s spark? Or? Thx.

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I found them. I may put a flashing cap on my snowblower. I have an in-line lisle spark tester that I can hook on if I change the end to straight.

Orergon, Stens, Rotary & Prime line all sell an in line spark tester with a red nenon tube so it flashes red when voltage runs down to the plug.
All the other ones use a tungsted element that flashes white which you can not see except in the dark.
A while back Boo listed the cheapest supplier so if you search Oregon spark tester it should come up.
About $ 20 on Amazon from memory
A very handy tool that you will use time & time again.

I was sure the 21's ran a kohler V twin which is why I said 2 testers.

bertsmobile1 said:

Orergon, Stens, Rotary & Prime line all sell an in line spark tester with a red nenon tube so it flashes red when voltage runs down to the plug.
All the other ones use a tungsted element that flashes white which you can not see except in the dark.
A while back Boo listed the cheapest supplier so if you search Oregon spark tester it should come up.
About $ 20 on Amazon from memory
A very handy tool that you will use time & time again.

I was sure the 21's ran a kohler V twin which is why I said 2 testers.

Click to expand...

It’s a single 16 hp CH16. And problem is solved with new pump with slightly modified actuator. Also noticed the 90 degree elbow fuel line that connects fuel line to carb was slightly kinked. I ordered a new elbow fuel line and in the meantime used a fuel hose clamp to keep the existing elbow from kinking. Runs great!