Fuel return check valve. Help!

1piece@atime · Post by **1piece@atime** » Mon Dec 17, 2018 2:59 pm

In the process of doing the first annual on my m-4 210 I noticed that the check valve is pointing away from the header tank. In other words extra fuel from the pump is not able to return to the header tank. I noticed this when I removed the return line from the engine side of the firewall and fuel was running out then looked at the check valve and the arow was pointed towards the pump. Is this correct or does it need to be turned around. If itâ€™s not correct could it have damaged anything. The plane was running fine and as far as I know itâ€™s been like this for a long time. Iâ€™m gonna call the factory tomorrow and see what they have to say. Thanks

crbnunit · Post by **crbnunit** » Tue Dec 18, 2018 10:42 am

I think this is correct. I believe gravity supplies the header thank and the fuel pump draws from the tank. There are smarter people on her than I am though. I don't remember a check valve on mine...

TimB · Post by **TimB** » Tue Dec 18, 2018 9:35 pm

see SL #31 or proper insatall

TimB · Post by **TimB** » Tue Dec 18, 2018 9:35 pm

see SL #31 or proper insatall

1piece@atime · Post by **1piece@atime** » Wed Dec 19, 2018 5:31 am

Thank you, That service letter is what I needed to see. Mine was put in backwards probably many years ago and I have corrected it. Now I just need to do some ground testing and hopefully get her back in the air. Itâ€™s been a month long annual and itâ€™s been interesting and expensive. New control cables, flap bellcrank brackets, fuel tank leak, many engine gaskets, many hinge bolt, headliner and replacement of the 1964 fuel lines. Good learning experience but I miss flying it.

freedom · Post by **freedom** » Wed Dec 19, 2018 8:50 am

since it costs nothing.. just blow in the vent line under the wing. if air goes in then you have installed them correctly.

crbnunit · Post by **crbnunit** » Wed Dec 19, 2018 7:05 pm

Interesting. I'll have to look at mine the next time I have that panel removed. I still don't remember a check valve on mine.

1piece@atime · Post by **1piece@atime** » Thu Dec 20, 2018 5:57 pm

Finally got the new lines on the plane tonight. After jumpstarting it off my truck it fired up and was running too lean. Next week we will put some gauges on it and get it tuned in. Gonna need a battery too. Whenever someone did the mod to comply with the service letter they put the assembly in backwards and must of adjusted the pressures to make it run ok.

HeavyLoad · Post by **HeavyLoad** » Sat Dec 22, 2018 10:01 pm

1piece@atime wrote:Finally got the new lines on the plane tonight. After jumpstarting it off my truck it fired up and was running too lean.

I had the same lean issue with a new overhauled engine. I had to following the contintal guide for adjustment.

Fuel return check valve. Help!

Fuel return check valve. Help!

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