My GMC at Home
Langley, British Columbia, Canada

Transmission overhauled at Dura-Built in Rocklin, CA.
Caspro 3.50 power drive was installed. Shift Kit was also installed.

As the transmission had quite a bit of metal in the pan it was considered best not to use the transmission cooler that is in the radiator. An external cooler was installed as sole cooler instead.

Regular ATF was installed by the shop. Synthetic was installed at first check and filter change.

Downtime was 3 days.

Fifty miles from home a big bang and rough running. Limped it home by keeping idle rpm up but staying below 40mph.

Found #6 cylinder exhaust valve gone. Top of piston damaged, but no hole(s).

Had the heads rebuilt. All parts replaced with new. Exhaust crossover was welded shut.

Upon reinstall, compression was good. Howell TBI was removed and Rance EFI was installed at this time.

Compression:
#1: 153, #2: 138, #3: 145, #4: 138,
#5: 140, #6: 137, #7: 140, #8: 135

A 20/20 hindsight note: Compression was done with fuel pump active. This means that cylinder walls got washed down with fuel with resulting inaccurate compression readings suspected.

Compression:
#1: 136, #2: 134, #3: 138, #4: 136,
#5: 136, #6: 135, #7: 137, #8: 135

Installed four bagger suspension system.

Rear bearings repacked.

Left/Front Rear Wheel Cylinder replaced.

Left/rear Rear Wheel Bearing had most wear.

Onan Genset: New ring gear, points, plugs and started cleaned.

Chassis Lube
Oil 15/40
Filter: Fram Teflon DG25
Front Wheel Bearings greased

Front Tires to Bridgestone R265 LT215/85R16 E rating (10 ply)
Front Alcoas polished and balanced.

Installed rear Disc Brakes

Compression:
#1: 125, #2: 120, #3: 130, #4: 125,
#5: 120, #6: 130, #7: 120, #8: 125

#7 with open throttle: 150

Change AC clutch bearing.

Modify alternator +12 Volt to insert a flexible connection as strain relief for the #4 cable.

Installed Fuel Pressure gauge.

Installed combination RPM/Vacuum gauge.

Oil changed to 5/50 Castrol Synthetic.

Oil Filter changed.

Transmission changed to Synthetic. Filter changed. Additive added.

Chassis Lube. ( Front Bearings not greased )

Compression:
#1: 145, #2: 120, #3: 136, #4: 120,
#5: 131, #6: 120, #7: 130, #8: 115

Additional reading of #1: 120.

Comments: Fuel appears to dilute ring seal. All plugs wet after first. Compression was taken with one plug out at a time.
Sequence: 1,3,5,7,2,4,6,8,1.

Gap checked to 0.080. Only 1 or 2 (unknown which) were slightly less.

NEXT COMPRESSION TEST: Disconnect Fuel pump prior to test.

Transmission modulator adjusted 3/4 turn out. (anticlockwise)

Steering box adjusted 1/2 turn in ( clockwise)

Oil changed: 5/50 Synthetic
Filter changed
Chassis Lube
Front Bearings: checked grease, didn't take any.

Parking Brake tightened 3/4 turn

Compression:
#1: 135, #2: 155, #3: 150, #4: 155,
#5: 162, #6: 145, #7: 162, #8: 157

Additional #6: 150. This was the cylinder that made an exhaust valve disappear.

Compression was done with fuel pump disconnected and all plugs out. Sequence: #8 --> #2 and #7 -->#1.

Plug gaps ok. #1, 3 and 2 showed rich.

Installed Auxiliary Vacuum Pump, AV10 Engine Monitor, Ragusa Step and other Ragusa goodies.

Final Drive fluid changed to Synthetic. Ragusa Cover installed.

Fuel filter changed. Some metal flakes in filter.

Spark Plugs replaced with R46SZ at 0.060 gap.
Used a gap of 0.080 prior to this.

Lubed Parking Brake worm gear.

Compression:
#1: 152, #2: 150, #3: 140, #4: 147,
#5: 133, #6: 145, #7: 150, #8: 143

Plugs condition:
#1 - Lt Brown
#4 - Gap: 0.055
#5 - Brown / Gap: 0.057
#8 - Lt Brown+ / Gap: 0.055

Plugs regapped to 0.060

#5 replaced.

Timing Chain replaced.

Cam Shaft "button" installed.

Mondello Water Pump installed.

Thermostat replaced with Mondello restrictor.

Alternator mounting bracket modified with studs used for mounting instead of bolts and .25 inch of spacer installed to improve belt line-up.

New Delco rebuilt Alternator installed. Ser# 1972724, 321-136, 18E8. Purchased in Sacramento. Ford E7AF-10A352-AA pulley installed with Loctite 640 on shaft and 242 on threads. No lock washer used. (no room).

LH Exhaust gasket changed. FelPro 1439 was used.

Battery Combiner installed. Alternator to Battery cable replaced with #6 size. A second combiner will be installed to charge the engine aux/boost battery.

Prior to this change the rear (house) battery and the aux/boost battery were always connected in parallel, perhaps contributing to frequent battery failures of the aux/boost due to the mis-match to house battery.

Each battery bank is now on it's very own.

Battery status indicators installed on engine and aux/boost battery.

Second combiner (50 amp) installed between main and aux/boost battery. To actually use the boost battery will be by normal switch/relay in the coach.

New caliper installed on right rear/rear.

New Master Cylinder installed (Raybestos). Brake pedal went to floor even after re-bleed. Front brake reservoir was colored redish. Old MC was leaking on the vacuum booster side.

Debating re Raybestos/Wagner versus Cinnebar/GMC.

Installed new transmission filter, transmission cooler with fan and a transmission fluid thermostat.

Rebuilt rock guard.

Rewired the coach charger with #6 wire and cleaned up house battery wire connections.

Wired up the regular/high output selection switch on coach charger(s).

Added AC outlet in Generator compartment, connected to the unused 20 amp breaker on GenSet.

Installed E-Meter connected to house battery.

Did a short neighborhood test drive.

Brakes ok (with Raybestos MC).

Water temps too low (133 degrees). Removed Mondello restrictor and installed 180 degree Robert Shaw thermostat.

Caspro Steering Damper installed.

DOA Combiner replaced.

Installed remote switch for Combiners on glare shield so that batteries can be combined manually or forced to "no combine".

Installed monitoring lights for electric fans on glare shield so that there is a positive indication when they get turned on by thermostat or manually.

Various rewiring & cleanup. Installed a drip protector inside driver side front access door to protect fuses and terminal strips.

One hour test drive.

Front Calipers and Pads replaced.
Calipers: Wagner: L80940 / L80941
Pads: Wagner Severe Duty, Carbon Metallic: SX52

Steering Damper was loose. Retightened and ground to increase clearance to Final Drive pan.

Chassis Lube, Oil & Filter changed.

Installed additional tailpipe ring.

Front Bearings: Right added none, left: a tiny bit.

Changed LH exhaust header gasket to a Mr Gasket. (It failed 1000 miles later and was replaced with a Felpro).

Compression:
#1: 140, #2: 142, #3: 136, #4: 140,
#5: 137, #6: 142, #7: 144, #8: 140

Plugs condition:
#1-4 - Brown
#5 - Black
#6 - White
#7 - Brown / Gap 0.065
#8 - Black / Gap: 0.058

Reinstalled plugs switched and with Dielectric paste

Chassis Lube, Oil & Filter

Hatch rebuilt to accommodate Offenhouser intake manifold.

Air intake relocated to behind alternator.

Wheel nuts retourque'd

Air to 65 pounds.

Problems on trip: Lost lower LH shock nut. Replaced with self locking nut in Prince George.

Alcoas changed (recall)

Tires: Michelin XPS 10 ply ( Load Range E) inflated to 65 pounds. Wheels were balanced with TireSentry transmitter in place.

Installed SmarTire monitoring system.

Rear bearings had slight play. Reseated all. Tightenedd to 50# and backed off 1/6 to insert cotter pin.

Compression:
#1: 170, #2: 155, #3: 162, #4: 160,
#5: 162, #6: 171, #7: 164, #8: 161

Plugs condition:
#1 & #5 - Black, rest brown. No white.

replaced with new plugs at 0.060

Chassis Lube
Oil & Filter

Rear brake pads at 50%

RR Caliper/Pads normal (Caliper and pads changed recently as old one was dragging)

Replaced City water connection and check-valve.

Changed O2 sensor to Bosch 13077

Fuel pump was on for the first few turns of the engine.

#5 Wire needed crimping.

EGT on 4 & 6 went 60% of normal heading up to Merritt. Cleared up itself.

Steering box and shaft changed (Caspro).

Power Steering filter added.

Oil and Filter changed.

Front Bearing greased (carefully)

Changed Master Cylinder
Booster
80mm Front Calipers
New Front Brakehoses

#5 darker but not fouled.

Changed Fuel Filter (Old had water and some dirt trapped)

Tranny filter (in pan) changed
Tranny in-line filter changed
New Ragusa Tranny pan installed (Old: rock damage)

New Plugs: R46SZ .060

Changed Oil and Filter after running engine to normal temp.

Ran GenSet

Trip to Costco

Ran GenSet and A/C

Ran a few miles, all smooth.

Ran GenSet

Ran it to temperature.

Used only GasketMaker on Ragusa pan

Changed LF shock as it seemed stiff and may have exerted extra pressure on the bracket.

Chassis Lube
Final Drive checked: OK

Removed external Tranny filler/dip-stick and re-installed original.

Air Filter & Oil Breather cleaned and re-oiled (K&N)

Oil & Filter changed

W/S Washer cleaned out and water stray point repaired.

Wiper tick: arm is hitting on Master Cylinder.
Bent sufficiently to clear.

Weighed the coach

Fuel: full
Fresh water: 90%
Holding tank: normal empty
Load: Ready for travel:

Front set: 3968
Rear set: 7716

Front set, front seats loaded: 4321

Front right: 1918
Front left: 2028

Rear right: 3792
Rear left: 3902

Have adjusted tired pressures to front: 60 and rear 55 lbs. Ride is much better. Will keep an eye on tire temperatures via SmarTire system.

Added some roof sealing to the from Cap area. Hopefully that's where we were leaking. Used PlastiKote.

Engine battery replacement: original tray badly rusted.
Installed new engine battery tray (Ragusa)

Installed two fresh engine batteries (Wal-Mart)

Using Trojan T-105's

Decided to use the 20 amp as this one will be on all the time and I wanted it quiet, without cooling fan. Installed with remote and a temperature sensor above the unit to enable monitoring.

Engine:
Oil (Mobil 1 15/50)
Filter: Fram PH25

Tires: Front - 61.5, Rear - 57

#5 plug: low EGT, black, gap was good. - Changed.

#8 checked - good burn.