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Bob_pipedream

Active Member
Hi all,

Quick three questions before I reassemble my carb.

Does anyone have a pdf of the service manual for the MA-4SPA?

What torque do I do the throttle body to bowel screws to?

Has anyone used a smear of fuel lube on the gasket when assembling the throttle body to bowl?

Thanks,

Bob
 
manual

I have the service manual. Send me your email address. I purchased a rebuilt engine for my 7a that hadn't been run for a couple years. I tried cleaning the carb (boiling in a solution and new gasket kit) but I wasn't happy with my engine performance. The minor adjustments on the carb didn't give me the power I wanted. I finally bought an overhauled carb from Spruce and gained 10 knots. Don't know if I didn't put the carb back together properly, I did have help from a knowledgeable mechanic, but I couldn't get proper operation. Just a personal experience for thought. Randy
 
Be careful...

Bob_pipedream said:
Hi all,

Quick three questions before I reassemble my carb.

Does anyone have a pdf of the service manual for the MA-4SPA?

What torque do I do the throttle body to bowel screws to?

Has anyone used a smear of fuel lube on the gasket when assembling the throttle body to bowl?

Thanks,

Bob
Click to expand...

...to get the mixture control in its well in the bottom of the carb during assembly. For whateever reason it is slightly misaligned and needs to be guided in. The shaft is a spring, so it is possible for the brass piece to wind up outside the well. If it winds up outside you will have no mixture control and no idle cutoff. (This carb was originally used on John Deere tractors and modified for aviation use with installation of the mixture control)

When I confessed the mistake to my A&P, he told me he made the same mistake on the first carb he overhauled too.

LarryT
 
Thanks all,

Randy, I have sent PM with email address.

Given the SB on leaking gaskets between throttle body and fuel bowl, I will torque the screws up to 50 in/lbs and then leave it over night and just before installation I will re-torque them as it seems that the gasket can compress and cause leakage issues.

Still not sure whether to use a very thin smear of fuel lube on the gasket surfaces though?
 
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Carb Assembly

Bob,

When I installed new floats, the Tech Counselor who helped me used fuel lube on the gasket--just a light smear. He said it would help keep the gasket from sticking to the carb housing next time it was disassembled.

John Ciolino
 
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