On December 29th we
decided to head back out into the wilderness and bash around, rather than
installing the new parts from Lada World, and this time we took Andrew and Robb
out who followed in the SVT Raptor. Driving along, the Lada performed very well,
able to climb the rolling hills and maintain the 100 kph speed limit with ease.
Once we hit the trail head it became pretty clear that the pathways were much
too narrow to run the wide Raptor without serious paint damage, so we parked it
and everyone loaded up in the Lada.
We toured around the fresh snow
and made it further than before, but the deep snow and extra load made for hard
going, and we retreated and took a break back at the normal bivy site. We had
gotten the engine pretty warm, but everything held, the overflow coolant
bubbling like a witch’s brew in the degas bottle.
After enjoying a nice fire and a
hot beverage, we mounted back up and prepared to roll out for home. Soon after
we got under way, we noticed the Lada wasn’t acting quite right, it refused to
idle and the air-to-fuel ratio was excessively lean, even at idle. Driving, it
lacked the power to cruise properly and stalled out when approaching stop signs
and bump restarting with the clutch was necessary to keep it alive. Shawn began
to wonder if the mixture screw had come out of adjustment, and once we pulled
home and checked it, he was more than right. Our mixture screw had not only
come out of adjustment, it had fallen out of the carburetor and was lost
forever.
To fix this, we visited the
junkyards later in the week searching for an old Volkswagen with a similar carb
to harvest parts from. We had very little luck locating any carbureted vehicles
so we had to settled for two options, one from a Ford Motorcraft 4-barrel,
(needle style) and another from a Toyota 20R 2-barrel (blunt style). Back at
the shop both of these screws fit in carb, and were even in the right thread,
but it wouldn’t be quite that simple. The Ford screw allowed the engine to idle
correctly but when adjusted to 14.7 AFR we only had one or two threads engaging
the carb body, it would surely vibrate loose and be lost, just like the
original, we moved on to trying the Toyota one.
This one bottomed out with making
any impact to the overall idle mixture, so Shawn figured we could profile a
“needle” into this blunt ended bolt and maybe have something workable. I
remembered a method I had used in place of a lathe for crudely turning down
sockets to fit in tight areas and set up a similar rig. The angle grinder was
flipped onto its back and clamped in the vise, the bolt was chucked up in an
electric drill, and from there each of us ran a power tool. With each spinning
in the same direction it was a simple matter of picking the angle of the cut,
15 seconds later we had a nice fine cut needle.
Tested on an idling engine it
worked perfectly, small adjustments allowed progressive changes to the idle
mixture and soon it was pegged at 14.7 and behaved very well, all of the
previous hesitation and bogging had
vanished, the retention spring ensured this one was unlikely to fall out.
After a positive road test we
sized up the next project, installing the Lada World supplied Layshaft and
donut flex coupler.
The night of January 11th,
2013 we began work on what would serve to be the most involved Lada project to
date, starting with the inspection and assessment of the differential. As you
may recall we had serious issues with the center differential thrashing about
under load and we had been able to confirm that the layshaft was indeed
striking parts of the body, once we removed the center diff mounts and
interior, the problem became very obvious.
The floor had been heavily over
the years and had cracked where the passenger side center diff mount was
located, and judging by the severity of the damage, we were in for some
reconstructive work.
The original floorpan is very
thin 18 gauge metal, with a studded backing plate of similar thickness that was
spot welded to the floor for hanging the differential. On top of all this rode the
front seat mount, a lot of load on a small area which clearly wasn’t up to the
task. We built a rough list of materials, sheet metal, 1/8” thick plate, rust
convertor paint and spray in rubber bed liner for sealing the floor.
Later the next day we had all of
the materials in hand and set to work, Shawn expertly repairing the torn floor,
then a large patch was made with a number of holes for plug welding to the
transmission tunnel. Once anchored, the reinforcing patch was heated with a
torch and hammered to match the contour of the transmission tunnel, and then
plug welded and allowed to cool. This gave us a very strong patch with a very
crude from of heat treating. The new center differential mount was made from a
much larger piece of 1/8” plate with was placed on the fresh patch, stitch
welded securely. Two holes were drilled from the underside to locate the new
mounting studs, which were made by simply dropping two correctly sized bolts in
from the top and welding the heads to capture them.
Finally the seat mount was placed
back on top and it too was welded into its original spot. The driver’s side
seat mount received a similar treatment as it too was damaged, but not to the
point of the passenger side. A coat of rust preventative paint sealed the metal
from any corrosion while the spray in rubber bedliner was used to glue the
underlay into place.
The photos tell the tale:
 |
| Original mounting plate shown, not for reuse. |
With the center differential mount
problem solved, it was a very quick matter to install the new CV layshaft and
the upgraded guibo isolator. Inspection of the old parts found the universal
jointed layshaft in good condition, but the rubber donut isolator was certainly
shot, it had many deep cracks that ran 1/3 of the way or more through the
material.
 |
| Better than new! |
With everything back together it
was time for a road test, and after a slight center differential alignment
adjusted the Lada was again better than ever before. The driveline shake was
gone and power delivery to the wheels was much smoother overall.
Soon it would be time for another
off-road test!
