Thunderbolt by Bob Atwater, Seneca, South Carolina
16 November 2010 Update (Cont'd)
Boat on trailer being inspected by a Poodle.
Most of the fixtures/fittings from the mockup, except for
the drive train, are relocated onto and into the hull. Gauges
installed and wired.
Finally, the drive train is dropped into the hull. The
mounting holes in the motor stringers were predrilled using
dimensions and locations taken from the mockup. It was
necessary to relieve a couple of holes for a final fit.
The front of the big block is a bit closer to the rear deck
than anticipated. Overall, however, it went quite well.
View of the drive train after rebuilding the transmission.
Yeah, we managed to tear it up before the boat ever saw
water. Somehow there was a snap ring missing on the hardened
shaft between the engine and the transmission. Nasty noise.
I could not imagine trying to steer, shift and control the
speed all with two hands. Therefore, I installed the
"Hot Shot" foot throttle. It is very awkward to me
as it is for the left foot (will not fit for the right foot).
My friend has no problem.
The small cooler is for transmission oil. The tank is one of
two 10-gallon aluminum gas tanks frequently seen on Dune
Buggies. I could not find an off the shelf tank that would
fit down between the fames and motor stringers. Custom
fabricated tanks were outside my budget at this point.
The "Lake Test" in June 2009. I was concerned how
the Thunderbolt would sit in the water with a big block in
the back. Looked good.
Yours truly checking for leaks. I took the opportunity to
crank up the engine and check as much as possible while still
over the trailer.
In early 2010 I put the Thunderbolt in the water for its
maiden voyage. It was incredibly noisy, not just the engine,
but the transmission and v-drive. After a short run, trying
to shift from first into second, I thought had torn up the
transmission again. Frustrated, I put the Thunderbolt back in
storage.
My friend, Tommy, who owns Progressive Marine in Seneca
thought I was crazy when I started the project, but fell in
love with it as it came together. He asked if he could check
it out at his yard. He did. Then he wanted to test it in the
water. He did. This photo taken November 9, 2010, is the
third time Tommy has been in the water with the Thunderbolt.
We had a few minor problems to iron out initially and
adjusted the trim plates a couple of times. He is passing by
at a leisurely 80 mph turning 4700 rpm on a 12 "
diameter, 16 pitch prop and reports that there is plenty of
throttle left. He has no problem shifting from first to
second as long as he keeps the rpm over 3000 in first at the
time he shifts.
Going away! The Thunderbolt has been put up for the winter.
In the Spring, Tommy wants to see how fast he can go from
stop to full out. I need a better camera for that. We might
tweak it a bit trying a higher pitch prop. After that, I will
have to get rid of the Thunderbolt. I have two grandsons, one
presently with a driver's license and the other a couple
years away. There is no way they will ever be allowed behind
the wheel of the Thunderbolt which I expect will scream down
the lake at over 100 mph.