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General control line discussion => Open Forum => Topic started by: Robert McHam on November 12, 2009, 10:55:45 AM

Title: Why won't my engine keep running? A beginner's lament.
Post by: Robert McHam on November 12, 2009, 10:55:45 AM
When so many of us started out with hollow logs as a first or second
attempt at flying, I found how a simple mistake can just ruin our
perception of certain brands of engines.

I recently acquired this cool little Scientific Zig Zag which most likely
has never flown or flown very little. Either way, I found two problems
that can be attributed to this particular plane.

First the stock fabric hinges were completely doped over which would
make the control stiff and almost nonexistant.
Second, the tank was mounted upside down and at a strange angle locating
the pick up tube to the inside of the circle. Of course this would
severely restrict engine runs, giving the impression there might
be an engine problem.
The engine in this case is an AMF Wen Mac Mark XI 049 and could have been
the brunt of many an ugly comment!

Since the tank was buried in the fuse and unseen, one could only assume
that it had been installed correctly.
The only reason I know it wasn't is because the plane was in need of
repair when I purchased it and the wing had been broken from the fuse.

I have to wonder how many little slip ups were made and never found out or
corrected contributing to the ill will towards engine brands, fuel or the
hobby in general!

Robert
Title: Re: Why won't my engine keep running? A beginner's lament.
Post by: Robert McHam on November 12, 2009, 10:59:02 AM
I really should add the shot of the tank.

Robert
Title: Re: Why won't my engine keep running? A beginner's lament.
Post by: Bill Adair on November 12, 2009, 01:21:56 PM
Looks like the tank was cast in a solid block of Ambroid cement !!!  ;D

Are you going to remove it, and install it properly?

Bill
Title: Re: Why won't my engine keep running? A beginner's lament.
Post by: John Stiles on November 12, 2009, 01:35:13 PM
Maybe somebody put the fin on upside down and the wheels....... LL~ JK ;D
Title: Re: Why won't my engine keep running? A beginner's lament.
Post by: john e. holliday on November 12, 2009, 03:35:43 PM
Yes I have seen planes like that in which the person did not read the instructions or misinterpreted them. n~
Title: Re: Why won't my engine keep running? A beginner's lament.
Post by: Robert McHam on November 12, 2009, 04:16:24 PM
Looks like the tank was cast in a solid block of Ambroid cement !!!  ;D

Are you going to remove it, and install it properly?

Bill

Heh! Bet he had to make an extra trip back to the hobby shop for more Ambroid to finish the job!
Instead of "apply cement sparingly" he slathered it on.

Had the wing seat been intact I probably would have never found out what I know now. I have already removed it as it would never work in that position. Also the tank is  a #3 perfect tank which has a capacity of three quarters of an ounce.
Doing the math, 8 CCs (the size of a Golden Bee tank) is just over one third of an ounce. Three quarters is just too big in the first place. I think I just want to restore it for display for now with no tank at all. Someone went overboard with all the cool paint colors and put a lot of work into his "masterpiece" I respect that.

Robert
Title: Re: Why won't my engine keep running? A beginner's lament.
Post by: Chris McMillin on November 18, 2009, 12:06:50 AM
Wen Mac Hot Shot MK XI's are pretty good runners. With a Cox 6x3 or 6x4 and 25 to 30 percent nitro they chug along very well. I always thought it was the Wen Mac propellers and fuel that made them seem weak. I used Cox stuff on everything, Cubs and Atwood Wasps, etc.
On 35 to 42 foot .008's that tank is enough for the AMA pattern. Golden Bee tanks aren't enough for the pattern.
Chris...