M-7 235 vs M-7 235B

Trigear? Taildragger? Fixed pitch prop? Which Engine? ...anything related with model selection considerations and questions about buying a Maule
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Hawgsforever
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M-7 235 vs M-7 235B

Post by Hawgsforever »

Looking at several M-7s for purchase and looking for insight on the different years/models.

Wondering if anyone out there has any insight on the differing handling characteristics of early M-7 235s with the long wing/long flaps/shorter ailerons versus a more recent M-7 235B with the "universal wing"/shorter flaps/longer ailerons.

Specifically concerned with takeoff and landing performance differences, stall characteristics, and roll control at slow speeds.

Thanks for any help from anyone who has significant time in both...especially if on bush wheels and floats.
Hawgsforever
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maules.com
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Post by maules.com »

There are subtle differences but not enough to base a purchase choice if you see a good one.
The long 33'8" M7-235 has the shorter aileron and longer flap thus can fly a tad slower at bottom end at the expense of roll control.
The 33'8" M7-235A has the 7" longer aileron thus 7" shorter flap.
The top skins on these wings is .020
The universal wing 32'11" M7-235B and M7-235C(wide gear) is slightly faster in cruise and slightly faster at stall, however rigging, drag factors(tyres), etc can make these differences imperceptible.
This universal wing has a stronger .025 top skin.
Micro aerodynamics VGs are a great aid for aileron and elevator effectiveness.
Many Maules are not rigged correctly for ultimate performance so this can make a big difference.
There are O540J1A5D, O540J3A5, 2400rpm, and O540B4B5 carb engines, the latter having lower compression to anable autogas but 2575 rpm so the long prop cannot be used.
There are IO540W1A5D and IO540W1A5 injected engines 2400rpm
There is IO540V4A5 injected 260hp 2700 rpm so no long prop
There are 8 different propellers available which also all make a Big difference

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Isaac
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Post by Isaac »

I agree with Jeremy. I learned in a 235B model on 31" tires and now fly a '84 235 on 35" tires for a living. My current long wing M7 is the most capable off airport hauler I have ever seen. I have flown another long wing Maule that wouldn't land as slow or cruise as fast as the B model I started in. I would take a known good preforming B model over an unknown long flap model M7.

Hawgsforever
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Post by Hawgsforever »

Jeremy and Isaac. Thanks for the insight and answers. I am working pre-buy A&Ps. Just wanted some insight whether the long wing vs universal wing aircraft were significant enough to sway a decision and it does not appear so.
Hawgsforever
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M7 235 engine

Post by Maule lady »

What is the difference between O-540 J1A5D and the O-540 B4B5 engines I have a 1989 M7 235.

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Post by maules.com »

J1A5D is 235hp carb 2400rpm 8.5 compression
B4B5 is 235hp carb 2565rpm 7.2:1 comp and thus can burn auto gas with no ethanol and needs STC. The Rpm precludes use of the 86â€￾ prop.
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51598Rob
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Post by 51598Rob »

So, max 82, or 84?
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Post by maules.com »

Max certificated prop length for B4B5 is 80â€￾ three blade and 81â€￾ two blade but MT dealer in Wisconsin can get their 83â€￾ approved I understand tho it’s pricey.
J1A5D and IO540 W1A5 can use the 86â€￾ two blade also.
Jeremy
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