Help! Leaky CheckValve on IHC-M

[RangerBob]

Help!

I have a real nice 3ph IHC-M. Looks great, starts great, runs great. The only problem, is that I have to pour a prime into the mixer, prior to starting, because the mixer bowl drains back into the tank. I have 'overhauled' the fuel pump. I found that the fine wire spring was on top of the ball under the plunger. I felt that it should be on top of the other ball (on the way to the mixer). Still leaks back overnight. Ball look good. Is there a way to 'dress down' the seat?

Any help would be appreciated.

Bob Waldron
Stillwater, MN

[BDMelon]

Originally Posted by RangerBob

Help!

I have a real nice 3ph IHC-M. Looks great, starts great, runs great. The only problem, is that I have to pour a prime into the mixer, prior to starting, because the mixer bowl drains back into the tank. I have 'overhauled' the fuel pump. I found that the fine wire spring was on top of the ball under the plunger. I felt that it should be on top of the other ball (on the way to the mixer). Still leaks back overnight. Ball look good. Is there a way to 'dress down' the seat?

Any help would be appreciated.

Bob Waldron
Stillwater, MN

i have a small dowel rod with steel ball expoy to it , then i put valve lapping
compound on steel ball, run that down on seat, just like running in valves
Brian

[Andrew Mackey]

Is your engine a kero burner, or straight gas? If kero, you want the drain back, so the engine can be started on gas. if it is a gas burner - 1) is the pump die cast Yanuck (a zinc alloy), or cast iron? 2) is the discharge on a 45 degree angle, or does it come out at a parallel to the inlet? (bottom ) have you checked the ball check seat for concentricity?(is it round?) Often the check seats off center, and you may have to replace the pump body) Is the ball perfectly round, and without pits or dinks?(should be shiny clean) The seat should also be clean.

If the seat is scarred, I take a pencil, remove the eraser, buy 2 new brass check balls the same diameter as yours. Epoxy one of the new balls to the eraser mount, after removing the eraser (pull out with pliers). Let epoxy set 24Hrs, and then apply fine grinding compound to the ball. Remove the pump plunger, and the check balls and fuel lines. Use the eraser to lap in the brass ball. When you see s solid line in the circumferance of the seat, wash out the pump with kerosene, very thoroughly , and re-assemble pump. On my 3 HP engine, the gump is cast iron. All other pump parts were brass.

[Mtype]

I have done the same as bd on probably 10 m type fuel pumps and a few other pumps. it also work very well on wla harley oil pumps. Cam

[Joe Morris]

[QUOTE=RangerBob;181804]Help!

I have a real nice 3ph IHC-M. Looks great, starts great, runs great. The only problem, is that I have to pour a prime into the mixer, prior to starting, because the mixer bowl drains back into the tank. I have 'overhauled' the fuel pump. I found that the fine wire spring was on top of the ball under the plunger. I felt that it should be on top of the other ball (on the way to the mixer). Still leaks back overnight. Ball look good. Is there a way to 'dress down' the seat?

Any help would be appreciated.

Bob Waldron
Stillwater, MN[/QUOTE Bob,,]You are doing a lot of worrying for nothing. It is not uncommon for gas to leak back over night. Just pour gas in the mixer .crank it up and let it run. and enjoy it. M engines are known for leaking back over a period of hours. The ones that don't are the exception rather than the rule. You have the spring in the right place. Joe Morris

[Joe Morris]

[QUOTE=Joe Morris;181878]

Originally Posted by RangerBob

Help!

I have a real nice 3ph IHC-M. Looks great, starts great, runs great. The only problem, is that I have to pour a prime into the mixer, prior to starting, because the mixer bowl drains back into the tank. I have 'overhauled' the fuel pump. I found that the fine wire spring was on top of the ball under the plunger. I felt that it should be on top of the other ball (on the way to the mixer). Still leaks back overnight. Ball look good. Is there a way to 'dress down' the seat?

Any help would be appreciated.

Bob Waldron
Stillwater, MN[/QUOTE Bob,,]You are doing a lot of worrying for nothing. It is not uncommon for gas to leak back over night. Just pour gas in the mixer .Crank it up, and let it run, and enjoy it. M engines are known for leaking back over a period of hours. The ones that don't are the exception rather than the rule. You have the spring in the right place. Joe Morris

P S, I have had several Ms of different sizes over the years and have never had one that held gas over night.

[ErikG]

My 3 HP M drains back also. I have new check balls and polished seats. Before starting I always manually pump the fuel plunger to bring the fuel into the carb body.


Erik Grund
Bloomington, MN

[RangerBob]

Thanks to everyone for the replies. The M was originally a Kerosene runner (started on gas), and I have gas in the tank. The pump is the one with the output casting at about 25 degrees from the plunger casting.

I plan to 'lap' the seat as suggested. If it does NOT cure the 'problem' then I will adjust my mind to live with it.

I like ALL my engines, and I really like this M. It is so reliable.

Thanks again.

Bob