I am not going to go too in depth into rebuilding the L134 since there are
great instructions in the mechanics manual. I will take photos along the
way and give some pointers along the way. I am by no means an expert, so
some of you Jeepers out there may not agree with some of my techniques.
I pulled the
head while the motor was in the frame because I wanted to check the valves. |
To PROPERLY
remove the head studs, use a stud puller like this one. There are a
few others you can use. DON'T use vise grips. |
The stud
puller makes easy work out of pulling the studs |
Pulling the
oil pan and timing cover, I was surprised to find a chain driven timing
setup. In theory, my 3A should be gear driven. I'll have to do
some research. |
Well, the engine rebuild came to a screeching halt.
The motor I have is a WWII MB engine! The serial number is stamped on
the right of the block, and the timing is gear driven. It would be
wrong to leave this motor in my 3A, so I trying to locate a good civilian
L134. In the meantime, I will continue to work on the motor until a
civi motor turns up. |
The early 2A engines had chain driven timing. To my
knowledge, no 3As ever has this setup. |
The block is
upside down on an engine stand in this photo, but with the side valve
compartment cover taken off, you can see the valve springs. At the
top, is the mount for the oil pump. |
With the head
and studs removed, you can get a good view of the cylinders and valves.
Lots of carbon build up! |
I use this
vintage ZIM cylinder ridge reamer to remove the carbon ridge at the top of
the cylinder. |
With the
reamer in the cylinder, use a ratchet to turn it. It will safely
remove the ridge so I can drop the pistons out the top once I turn the block
over. |
Bottom view
of the motor with the crank removed. |
With a dial
caliper, I check the size of the main bearing journals and the connecting
rod crankpins. |
Standard main bearing journals
should be 2.3341" to 2.3331", mine were 2.314", a difference of .020".
Connecting rod crankpins should be 1.9383" to 1.9375", mine measure 1.908",
a difference of .030" |
Ahah!
It's all so clear now why I had low compression! |
|
Using a bore gauge, I checked for
out of round and taper. The deviance can be up to .005", and mine were
within spec. Cylinder bores should measure 3.125" to 3.127", mine
measured 3.155", a difference of .030. |
Found the
correct engine block today! Both the casting number and serial number
match for my year of 3A. I was able to trade the old MB block for this
one. |
The inside of
the engine looks good. The block was painted red outside and
inside - anyone ever see this before? |
I measured everything on this
engine and it looks like it has been rebuilt. Here are the specs:
The cylinder bores measure 3.145", which is .020" over. The main
bearings measure 2.325", which is .010" over. And finally, the
connecting rod crankpins measure 1.918", which is .020" over. |
There is
always the proper tool for the job. Here I use a valve spring
compressor designed for flathead engines. |
Before
grinding the valves, I made a rack out of a 2x4 to keep them in order.
I also use a hand valve lapper and some grinding compound. |
Coat the
valve in a little grinding compound, and drop it in the seat. |
Rotate the
valve tool between both hands.... |
...and
presto, a clean valve seat! A unground valve is on the right. |
Next up, I
honed the cylinders with a course grit stone, and finished up with a fine
stone. |
It's hard to
tell from this pic, but the cylinder walls are good as new! |
My hands were pretty greasy, so I
couldn't take too many photos! I installed the valves and springs and
adjusted the clearance, installed the crank with new bearings and rear main
seal. Next I installed the pistons with new bearings and rings, timing
chain and cover, oil pump, water pump, and valve cover. |
Here's what
the motor looks like right now. It's awaiting the head and oil pan.
The motor is painted the correct factory black. |
The oil pan
got a good steam cleaning as was painted to match the motor. |
Before
installing the head bolts, I cleaned out the threads with a tap. Then
each bolt was coated in anti-seize to prevent then becoming one with the
block. |
This is the
motor awaiting installation in the chassis. |
The original
Fram oil filter was treated to a cleaning and repainting. The closest
color match I found to the original Fram orange was some Chevy orange engine
paint. The result was a nice smooth close to original finish. I
will ad some reproduction Fram stickers later on. |
Finally!
The motor was ready to be dropped in the chassis. |
Eugene is
slowly coming back to life! |
I threw in
this before photo just for kicks. Sure looks a lot better now! |
This sweet
shot shows the literally new motor and components. The distributor got
rebuilt with points, condenser, cap and rotor. A new 6v coil was
installed along with all new wires and sparkplugs. The oil fill vent
tube is original with the correct style hose clamps. That Fram oil
filter sure looks good! |
Back view of
the motor... |
The new
stickers for the Fram oil filter showed up today from Walcks. Here's
what they look like installed. |
Looks pretty
good! |
|