Question about Kohler 161 and it's fuel pump

[fireman 1,022]

Hey All

I tried to get the 753 started and wasn't getting any fuel. Pulled the carb and cleaned it out. Pulled the lines and made sure they were clear. Still nothing. So I decided to pull the fuel pump off. Well low and behold when I took it off, there was no fuel pump lever anywhere to be found . Anyone have any ideas. I'm hoping it didn't fall into the block . The pump looks new and i wonder if the previous owner never put it in.

:wh:

[TT-(Moderator) 1,145]

It's a vacuum (pulse) pump.

[fireman 1,022]

The manual I downloaded from Kohler says it supposed to have a lever. It even showed it in a picture. I will take pictures when I get home.

[TT-(Moderator) 1,145]

The vacuum/pulse pumps were used on the little Kohlers (on tractors) up until at least 1968.

If the body of the pump (near the mounting flange) is not drilled for the lever pivot pin, then it's a vacuum/pulse pump.

[fireman 1,022]

The one that is on there is not drilled. I will take it apart and see if the diaphragm is torn. Any thing else I should look for?

[VinsRJ 723]

If its the original 63 K161 it would have a lever style pump originally. Check through the lever opening in the block, there should be a cam lobe visable.

The 63 Wheel Horse K161 engine had the same specifications as a 63 Panzer K161, exactly. Although the "Spec Numbers" differed, they only denoted WH application versus Panzer application. All of the parts were spec'd the same.

[TT-(Moderator) 1,145]

All camshafts I have seen had the fuel pump lobe regardless of the type of fuel pump used.

You might be right about the original pump for the 753, but I know from past discussions that a vacuum pulse/pump is often mistaken for a mechanical pump that lost it's lever. Jeff stated that this pump looked like it was new, so I took a guess based on the fact that either style of pump will work on the K161.

@Jeff: the "check valve" discs might be glued in place by dried gasoline. That's the only thing I can think of other than the diaphragm.

[fireman 1,022]

The lobe is there. I will pull it apart and investigate. Thanks for all the help.

[64s 83]

Jeff and Vince, I'm with TT on this one. I'm showing that the fuel pump for the K161 spec 28626e is the same as the one on a 854. I know for a fact the the 854 had the vacuum/pulse fuel pump and you will see a cam lobe with the pump removed. If its original (the fuel pump), it won't have a lever.

[JimD 3,345]

While we're at it, I have a K181 that has no pump. I have two different style mechanical pumps with different levers on them, but neither one work on the engine, though they will pump fuel when you operate them by hand. What am I doing wrong here when installing the pump? I tried installing it with the pump lever on the top side of the cam, but they don't pump fuel. :)

[sorekiwi 761]

I have a 753 spec motor (28626E) and it has the vacuum pump on it. The pump has traces of old red paint on it that matches the engine, I am reasonably sure it is original.

Mine didnt work when I first tried to fire the engine. A good clean up, and its worked about 3 years now. Unless the diaphram gets a hole in it, there's not too much to go wrong there.

JimD, I have a mechanical K181 pump somewhere that I could take some pictures and measurements of. Let me know (but it might take a while to find it!!)

[buckrancher 2,694]

Jeff I have the diaphragms if you need one

[rmaynard 15,785]

While we're at it, I have a K181 that has no pump. I have two different style mechanical pumps with different levers on them, but neither one work on the engine, though they will pump fuel when you operate them by hand. What am I doing wrong here when installing the pump? I tried installing it with the pump lever on the top side of the cam, but they don't pump fuel.

Jim,

Check around the flange of the pump where the two halves go together. There should be a number cast into the aluminum. K181 should be a 231796.

Bob

[TT-(Moderator) 1,145]

K181 should be a 231796

It could also be other numbers, depending on exactly which pump it is.

Here are two 6/7/8hp pumps:

(the first one has the primer lever but you can't see it)

Crappy plastic version removed from an M8 Magnum:

"Typical" big block / single-cylinder pumps:

"Special" (severe duty, I believe) Carter K341/361 pump:

This should be a KT-17/19/21 pump:

I didn't want to hi-jack this thread, but this might help identify the various pumps for those who have questions. :)

[fireman 1,022]

How does the vacuum/pulse pump actually work? If it's open to the crankcase, how does it get the vacuum?

[TT-(Moderator) 1,145]

The vacuum/pressure pulses of air within the crankcase (created by the piston moving up and down in the cylinder) cause the diaphragm to raise and lower inside the pump housing, while the check valves inside the pump only allow it to push fuel to the outlet side of the pump while simultaneously pulling fuel from the tank.

It's essentially the same principal as the mechanical pump - except the lever that is moved up and down by the eccentric (lobe) on the camshaft is physically connected to the diaphragm.

[VinsRJ 723]

The vacuum/pressure pulses of air within the crankcase (created by the piston moving up and down in the cylinder) cause the diaphragm to raise and lower inside the pump housing, while the check valves inside the pump only allow it to push fuel to the outlet side of the pump while simultaneously pulling fuel from the tank.

It's essentially the same principal as the mechanical pump - except the lever that is moved up and down by the eccentric (lobe) on the camshaft is physically connected to the diaphragm.

TT, the pumps pics are great! Thanks for the documentation. :)

[JUSS10 250]

i built a diaphragm myself for mine. it wasn't torn it just sat so long it hardened with varnish. i just took a thin piece of rubber, cut to size and punched some holes in the corners. it works flawlessly :)

[fireman 1,022]

I took the fuel pump apart today and found both of the little one way valves lose and jingling around inside. No wonder it wasn't working. Cleaned them up and re-seated them, cleaned the diaphragm and put it back together. I put the pump on and cranked the starter. After a few seconds gas started flowing out of the pump. AHHH! success . Got everything else back together and turned it over. She fired right up and runs pretty sweet!!!

I want to thank everyone who posted with help especially TT. The pictures and information was a great help. I couldn't of done it without you guys.

This is just another example that RedSquare is the place to be if you collect Wheel Horse Tractors :)

[Handy Don 13,006]

This is a lever-actuated pump from my K181 on an 854 (as @ebinmaine noted). I am pretty sure it's not of original vintage since its check valves are not removable; you can see the indented "Vs" where the cover body was "flanged" over their edges to hold them.

The cover with the check valves has the inlet on the right and the outlet on the left. Both had debris preventing them from sealing properly but once gently cleaned they worked fine. You can see sand and other junk on the diaphragm. 

Diaphragm replacements are available (complete with plunger and upper and lower disks, but I'm not yet sure how to separate/re-connect the diaphragm and the actuating lever.

Edit: In the Kohler maintenance manual I just found that pressing down on the diaphragm disk and rotating it 90º releases it from the lever!

 

Edited March 22, 2022 by Handy Don

[pfrederi 18,119]

push down and turn 90 degrees

2 minutes ago, Handy Don said:

This is a lever-actuated pump from my K181 on an 854 (as @ebinmaine noted). I am pretty sure it's not of original vintage since its check valves are not removable; you can see the indented "Vs" where the cover body was "flanged" over their edges to hold them.

The cover with the check valves has the inlet on the right and the outlet on the left. Both had debris preventing them from sealing properly but once gently cleaned they worked fine. You can see sand and other junk on the diaphragm. 

Diaphragm replacements are available (complete with plunger and upper and lower disks, but I'm not yet sure how to separate/re-connect the diaphragm and the actuating lever. Today's project!

 

push down and turn 90 degress works on some types...