I have finally started to tear into my KG7H after having it sit for several
years in the basement. When I found it, it was just a pile of parts sitting in
a box. Someone before me must have run a little lean with the oil, because one
of the connecting rods snapped and sent needle bearings flying everywhere,
virtually destroying the block and crankcase. With the help of some of our
members I have been able to acquire all the parts I need to start reassembling
the engine. All that's left is to order some gasket sets, and odds and ends
from Grubbs. I will be compiling a sort of "blog" on the restoration
as I go. Every so often as more work is completed I will send in another entry
to our webmaster to post including pictures and a little note on how the
project is moving along. So without further ado, here is my growing story. If
you have questions or feedback, contact me at
here
I will be happy to hear from you.
My original pistons had large gashes in them from the needle bearings that the
engine ingested. I ended up sourcing a new set from an MLC member.
Here is the
way I received them. The first step in this project was to clean up the
pistons. I soaked them in ACDelco Cleens for a day and then used a 3M pad to
remove all the carbon deposits. I used an old broken ring to clean the ring
ridges. Once they were clean of carbon, using a combination of a hand held
dremel and product called DurSol, I
polished them up.
Part Two
Alright boys. I know, I've been slacking. A LOT has been done since the last
update, and I haven't been taking as many pictures as I should have. Either
way, I'll explain what has happened so far and include as many pictures as I
have.
I recieved my order from Grubbs for all the gaskets and odds &
ends I needed for the engine. Picked up my paint for the engine as well. Now
that I had all the parts ready to go, it was time for reassembly. I took the
block to the machine shop for a couple of helicoils in the waterjacket and
chased one of the spark plug threads that was really tight. I had to source
some used needle bearings for the connecting rods because the ones I had left
were so badly pitted. I then chose the best rods in my possession to use on
the engine.
I started by installing new roller bearings on the crankshaft with a press,
then the new torrington bearing in the crankcase. Next I cleaned up the reed
cage and installed it on the crankshaft. I then installed the crank into the
crankcase. I used two washers between the reed block and the crank throws as a
shim to keep from bending the reed stops while pressing the crank in. I then
installed the upper and lower seals. Then on went the rods. I coated the
bearing races of each rod with assembly lube and then laid all the roller
bearings in and carefully installed the rods. Next went the pistons and wrists
pins. The needle bearings kept falling out as the wrist pin went in, so each
wrist pin took a couple tries.
Now time for honing. I put the block in the Varsol tank and left the varsol
wash on the cylinder as I used the stone hone on a drill. Each cylinder ended
up taking a lot of passes to get the rust out of the cylinder.
I then installed new rings on the pistons. We set the crankcase in the vise
with the pistons facing up. Then installed the head gasket. I used a 2x4
between the piston skirt and crankcase to keep the piston from moving as I
lowered the block down on the pistons. I pressed the rings in with my fingers
and a small screw driver as I lowered the block onto the pistons. It required
a helper, and we really could have even used another set of hands. Once the
block was lowered onto the pistons, it was bolted to the crankcase. I then
installed all the parts onto the block. Intake blocks, exhaust port covers,
waterjacket cover. Once everything was bolted up I taped up the exposed
portion of the crank, as well as the carb opening so that it was ready for
painting.
Next step was to pull apart the gear foot and make sure everything is good to
go. I had the tool to remove the rear cone. The cone is reverse thread for
those taking one of these apart. I placed the prop shaft in the vise and
lightly heated (with a propane torch) the housing around where the waterpump
cup was seized in. I then hit the housing back with a rubber mallet and the
propshaft and bearing all came out as one piece. I then stuck a wrench in the
housing to hold the nut on the end of the driveshaft. I gave the shaft a turn
with a pair of pliers and all of that came apart no problem. I have left all
the torrington bearings inside the housing because they seem to be in good
shape and they look like a real PITA to change. Its a good thing I decided to
take apart the foot and check it out. All the blades on the impeller were torn
off and the roller bearings were cooked.
I have also rebuilt the magneto now. Removed the old cracked coils, took every
nut and bolt off the mag plate, put it in the varsol tank and got it looking
like new. I soldered new spark plug wires onto the new coils. I used a
dielectric grease around the solder and around the coil boot
opening to keep the moisture and corrosion off the solder. I then cleaned
up the points and installed new condensers. It's actually a pretty easy job
with the mag plate on the bench.
Now that the powerhead was all together there was a lot of prep work for the
paint process. The tower, gearfoot and clamps were all roughed up with a 3M
pad and then washed thoroughly. The tank and lower cowls took a lot of paint
stripper two remove the rainbow of colours that had been painted on them over
the years. I then used a conditioning disc on a die grinder to clean off the
residue. Then many coats of Bondo on all the major dents were applied. I then
sanded smooth. All the small steel pieces were either put on the wire wheel or
sandblasted to remove any rust before painting.
I used a self etching primer on all the lower unit pieces, and then painted
them a Dull Aluminum finish. 2 coats were all I could get out of
the can of paint.
My next installment will explain the major headache the tank and tank ring
have been and why the purist motor collector will hate me for hacking up the
ring. = )
Part Three
Someone along the way had used this gas tank as a football. It had massive
dents in it, and in hindsight, really wasn't worth fixing. A lot of Bondo was
used to smooth everything out. Also, the tank stud holes had been drilled and
tapped larger. The holes had also been drilled right through into the tank,
which meant i had to seal the studs in somehow so they didn't leak gas. I
ended up finding exhaust manifold studs off a Ford that fit larger holes. I
threaded them in sealing them with J B Weld. Now that the studs were taken
care of, i had to drill out the holes in the tank band to match the larger
studs in the tank. Once that was done everything was bolted back together. It
was a tight fit!
The tank and cowl were then shot in self etching primer and painted
with Peter McDowells amazing paint (note the plug for Peter paint). It
actually is amazing stuff. I wont paint another motor with anything but that
paint. Hard as nails and goes on really nice. Well worth the money.
The tank band was first wet-sanded over and over to remove as many
imperfections as possible. A simple Crappy Tire Dremel tool was used along
with polish to buff it. Once the desired shine was achieved i used a very
small modeling paint brush to do all the lettering in red paint. 2 or three
coats were necessary.
Bolted my carb on, set up the mag and then installed the tank and cowls!
Thats about it. It is pretty much done except for a few small cosmetic
details. Thanks for following along with the build everyone. I now have to
decide if i am going to keep it or sell it. I'm still trying to save up for a
condo!
