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505 Adams Drive / Rockville, IN / 47872

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Helpful Tips
Welcome to our Tips section. We appreciate your interest and hope that you find our advice helpful. If you have any questions, please do not hesitate to ask!


The Few Way's To Better Manage Your Time

Clutter can slow you down by distracting you from what you want to do. Take control, begin in one corner of the garage and straighten it up. Afterward, give yourself a reward for your good work

Do you keep "to do" lists that run on for pages and pages The most effective managers identify only three top priorities each day.

Before you begin a new hobby or pastime, consider eliminating an old one you've outgrown. Better yet, get rid of two.


Fender Interchange

1967 GMC&Chevy fenders are the same, 1968 Chevy &1969-72GMC Fenders are all the same,and1969-72 Chevy Fenders are all the same.All of the above fenders can be made to bolt to the other years and models that are not the correct interchange but this does mean body lines will not be correct for hoods and grilles.




Crank Pilot Bearing Removal

Fill opening of pilot bearing and behind with grease take a bolt slightly smaller than opening and wrap with a single layer electrical tape place bolt at opening filled with grease and tap hex end of bolt with hammer.You may have to remove bolt occasionally to place more grease in but the hydraulic action of the bolt trying to fill the area behind bearing the grease occupies will slowly force bearing from end of the crank with minimal effort.:)

Swapping A Idiot Light Dash Out To Gauge Dash

The following is for a gauge dash this gives the numbered position of the wires in gauge dash and followed by what it supplies, then number from idiot light dash you move wire from.
1-Black with white stripe 18g(alternator) This runs from the 12g R wire from voltage regulator and should have 1-4amp inline fuse.
2-Tan (Brake warning light) Original position 2
3-Pink (Fuel Gauge) Original Position 7
4-Tan(Fuel Gauge) Original Position 4
5-Empty(not Used)
6-Dark Green (Temp. Gauge) Original position 5
7-Black(ground)Original Position 6
8-Gray(cluster light feed) Original Position 12
9-Medium Blue (Right turn) Original Position 11
10-Lt. Blue (left turn) Original Position 10
11-Lt. Green (high Beam indicator) Original Position 9
12-Black/w brown stripe 18g use wire ran from the junction block near battery mounted to passenger side fender with 1-4amp inline fuse located at junction block end.
Remove the wires from your loom plug and place the colors in the # on plug that corresponds with the color from list above. You will need to replace your idiot light temp. gauge for a temp. sending unit with gauges. The black and white wire feeds from the 12gRed wire off back of alternator and requires the use of 1-4amp inline fuses, this wire you need to make and run. The DARK BLUE wire that was originally in #1 position should be deleted because this was the idiot light for the oil pressure.


Ignition Switch Removal For 72 and Earlier
  Place key in off position, disconnect battery cable. Insert a small stiff wire into small hole in lock cylinder face and push. You will feel slight pressure as you depress the pin inside. While holding in on wire rotate key and lock cylinder Left( counter-clockwise) and remove cylinder by pulling outward. You are now able to remove ignition bezel and ignition switch from dash by rotating bezel Left (counter-clockwise) and then remove wire loom plug from rear of ignition after lowering.


Headlight Switch Removal
   First disconnect your negative battery cable to ensure headlights do not drain battery during switch removal. Reach behind dash and on upper side of headlight switch near dash face you will feel a spring loaded button depress this firmly while you pull out the switch knob. Once switch shaft and knob are removed you can remove switch bezel by rotating to left (counter-clockwise), and then removing nut behind bezel. Lower switch from dash and unplug wiring harness.


Vacuum Gauge Use
Connect vacuum gauge to base of carburetor to full vacuum source at idle. Then monitor your readings and compare readings to chart below. 

1-Steady gauge reading from 17-22 indicates normal engine in good condition.

2-A intermittent fluctuation at idle indicates a ignition miss or sticking valves.

3-Needle fluctuates as you increase engine speed indicates ignition miss, blown head gasket, leaking valve or weak valve springs.

4- Steady needle that drops at regular intervals indicates burnt valves or improper valve clearance, (the needle falls when bad valve is in operation).

5-A drifting needle goes high then drops goes high then drops in a steady movement indicates minor intake leak or improper carb adjustment.

6- A low reading but steady from 10-16 indicates late ignition or valve timing, low compression, stuck throttle valves, leaking carburetor or intake gaskets or a big cam.

7- Needle vibrates heavy at idle but becomes steadier as engine speed increases indicates worn valve guides.

8-A gradual drop in reading at idle indicates blocked exhaust system or excessive back pressure in exhaust system.
      That's troubleshooting with one.  Now for fuel mixture adjustment with one.
 Disconnect vacuum advance at distributor and plug vacuum line, start motor with timing light and a RPM gauge attached and set idle and timing to correct settings. Connect vacuum gauge to full unported vacuum at base of carburetor, now shut motor off and turn both idle mixture screws all the way in but be sure that you only use light pressure as you can turn the idle mixture screw past being lightly seated by twisting hard and then you are damaging the idle mixture opening with the needle causing it to flare the opening trashing a good carburetor body so please only lightly seat the needles. now back each out 1 1/2 turns, restart motor and check idle and timing and adjust as necessary to correct settings, now back each needle out slowly a 1/4 turn each alternating between the 2 until you reach the highest vacuum reading, check and adjust idle speed and timing, now repeat step one of backing idle mixture screws out alternating between the 2 a 1/4 turn at a time until you have reached highest vacuum reading again. Continue the process adjusting timing/RPM/idle mixture screws until you have no changes occurring and have reached highest vacuum reading possible. You have now optimized your timing idle mixture adjustments. Reconnect your vacuum advance while disconnecting the RPM gauge, timing light, and vacuum gauge.
 Ok now for monitoring fuel consumption with a vacuum gauge. 
 Connect the vacuum gauge to full unported vacuum and run vacuum line long enough for gauge to be in cab. Go for a drive monitoring the vacuum gauge. When you have high readings you are getting the most fuel economy possible, when you have low readings fuel consumption to efficient combustion ratio is lowered. By easing into your gas pedal rather than moving it rapidly you will notice vacuum readings stay higher which increases MPG

67-72 Cab Weatherstrip Installation

For the vent window seals you will need the Vent Window repair kit to install it as they use a blind rivet to install them and can not be installed with the use a regular rivet as it will cause problems with clearance.

If you are purchasing the kit with glue on door seals you will need the weather strip adhesive to attach the door seals.
For all door seals you should also apply to exposed portion of seal and the adjacent areas of door and cab surfaces after installing DC4X silicone spray or similar spray ( armor all) to prevent the door seal from freezing to door when moisture is present when freezing weather is expected to prevent ice forming and freezing the seal to the door. Prior to installing door seals you should make sure that there is between 5/32"-3/8" gap between the door and the metal flange that the weatherstrip attaches to prior to installing the seal, after door weatherstrip install you should cut a 45 degree angle in either end of the bulb portion of seal where they meet under the door seal to allow trapped air to escape.

For the installation of the division bar felt you will need common motor oil to apply to the metal allowing easier install of the special rubberized backing on the division bad felt so then after installation the oil softens and absorbs it in the specialized rubber coating causing it to swell and lock its-self in place making a nearly perfect water tight seal.

It's also recommend using a silicone spray in glass run channel of division bar felt and on glass run channel its self to facilitate easy rolling up and down of the door glass window.

For the windshield & rear window seal you'll need to apply caulking to the window lip opening prior to install to help in sealing the weatherstrip permanently to the windshield & rear window opening then apply weatherstrip cement beneath the outer lip after install. This all helps to prevent moisture entering and cement helps rubber to stay perfectly flat.

GMCPauls Truck Parts

505 Adams Drive / Rockville, IN / 47872