My 1968 C-20 Golden Anniversary Project

[GerhardH]

Today I was trying to repair my ammeter, but lost. Maybe somebody can help!
The ammeter was showing nothing from the beginning as I bought the car. was studying all the information about them here in the forum (vettevet etc.) and today was starting to investigate.

1. I tried directly with a nearly empty battery connected to the gauge, great action on the pointer

2. Than I was doing the same far away on the fuses, same great result, than connected the fuses again (measured before ok) and measured directly on the ammeter. Both contacts showed plus, means connected.

3. My shunt (The battery charging wire) and the "Splice" are looking original.

So after reconnecting I saw that indeed the ammeter act, if I switch on the light with no running engine slightly to "D" discharge and if I start the engine slightly to "C" charge, but only 0.03" from middle (zero).

Ist this normal or what can be wrong?

[Steeveedee]

I went and checked on my truck. With the engine off, turning on the headlights barely moves the needle. I know that the system works, because when I hook up a low battery it reads about half way up on the "C" side of the meter, which is about 30 Amps, as I have a 63 Amp alternator.

[tdangle]

At least yours works in the correct direction. If I turn my lights on with the engine not running it moves toward the C side and running with a low battery it moves toward the D side. Backwards, and I've verified all the wiring.

[68Gold/white]

I bought a volt meter conversion from a member here. Believe is user name is TBONE...it eliminates the amp meter. I like THAT!!! An amp meter doesn't tell me enough...

[RichardJ]

Steeveedee posted,
>> I know that the system works, because when I hook up a low battery it reads about half way up on the "C" side of the meter, <<

A voltmeter will not tell you that.

"0" volts is a voltage reading. It may not be what you think you need to see as a reading, BUT it is telling you that the current being used by the truck is being replaced by the output of the Alt and is maintaining a fully charged battery.

If you periodically check the Ammeter, just as you do your other gauges and suddenly it starts reading higher than normal, it may be time to start shopping for a new battery.
In my experience, when the Ammeter starts reading, even a needle width higher each day, you have somewhere in the neighborhood of 2-3 weeks before that battery is history.

A voltmeter will not tell you that.

[GerhardH]

Thank you guys, so far I'm happy that probably the system works. The only think is that you cannot easily see if the gauge is working, because it is all the time at nearly 0. But found a way to check after a good advise: The heater blower is sucking alot (together with lights and hazard flusher , at least than I get 3 needle widths to D.

Regarding the voltmeter, I like to add one later, because both information together cannot be bad. But C and D I like to have too, see comments above.

Regarding wrong direction on the gauge, assuming change both wires on the gauge terminal will correct them.

[GerhardH]

So next side job done: Steering gear changed, it was easier than expected but my time commitment was 10 hours, I have done this the first time.

Also good advises from
TX firefighter: http://67-72chevytrucks.com/vboard/s...d.php?t=614332.
Power Lee steering: https://leepowersteering.com/pages/h...entify-gearbox

Lesson learned:
Needs time
Pitman arm puller works great
Reed carefully the bleeding instruction.
You should have the right tool (socket for the pitman arm nut 1 5/16")

There is are difference between 7802644L (first design) and 7802644 (second design)- look e.g. for Edelmann spare Kits explanation: "The only difference between the two gear boxes is the Input Shaft Seal, the earlier models have a 13/16" OD Input Shaft and the later models have a 3/4" Input Shaft OD."

[GerhardH]

Some more pictures

Pitmanarm puller
Open wrench 5/8 and 11/16

[GerhardH]

5. Fill power steering pump with new fluid recommended for your vehicle,
6. While having someone watch the fluid level and adding fluid to the pump (Keep fluid above top of pump casting) crank the engine over using the ignition switch.
...
10. While you are cranking the engine over, turn the steering wheel lock to lock slowly at least 4 times to bleed the system, if you see any bubbles or foam enter the pump; stop and let the system rest until all bubbles has dissipated.

Have done alone and to fast :-(
Bubbles foam noises and additional waiting time.

[GerhardH]

Still not realy a clue which pump I have with this 7802644L. For sure Saginaw "S"

Assuming, but needs more measurements:

SAGINAW 800/808 GEARBOXES

This is the most common GM steering gearbox found in cars and small trucks from the 1960’s into the 2000’s.

The difference between the Saginaw 800 and the Saginaw 808 is the size of the piston. The 800 has a 70mm piston and the 808 has an 80mm piston. This is easy to measure from the outside of the gearbox. If you measure the end cap, the 800 is roughly 3” and the 808 is just under 3.5”

[GerhardH]

Will count the splines later to have a clear pictures.
Look at the rag joint, only 1/4 with splines.

After pulling the pitman arm, loosen the screws from the rag joint and loosen the 4 holding bolts the removing of the steering gear was not a big problem.

[GerhardH]

Diameter 3.5" means Saginow 808.
Length approx. 12.1 "
4-hole “H” mounting pattern. (approx. 5.675", 2.875", 4.4")

[GerhardH]

Inverted flare

[GerhardH]

some shaft measurements
pitman: 8 spline betwen the blind spline (Total 4 blind and 32 spline)
input shaft 13/18 (0.8125") and 36 teeth but counted 31 because of the flat part without teeth.

[RichardJ]

Whether you are pulling a pitman arm, tie rod, suspension component or steering wheel, it is always bad practice to remove the nut while using the puller.

Turn the nut to the end of the threads, then use the puller to pop the taper loose. This prevents any possible damage to the threads and prevents any parts from flying.

Old style PS bleeding method does work for these old Saginaw steering boxes, but the more modern method of using a Hand Vacuum Pump to suck the air out of the system, does a much better job of preventing damage, especially to the pump.

[GerhardH]

Excellent advise, thank you so much!

Got also an advise regarding the coupler teeth, see here:

http://67-72chevytrucks.com/vboard/s...d.php?t=810616

It seems that there is just 1/4 of the circle with teeth.

Joke: See the wire. Is this called drive by wire?

[GerhardH]

Some investigation about the power steering hoses:
Typ inverted flare, got the new one from PICKMUP in SS (stainless steel):

http://67-72chevytrucks.com/vboard/s...d.php?t=545846

Returen line is without hose (use 3/8" hose and clamp)

Return hose will normally need to be cut to length
High Pressure Line: Inverted flare fittings, one 5/8"-18 and one 11/16"-18
Return Hose: 5/8"-18 inverted flare fitting.

5/8“ = 0.6250“
11/16“ = 0.6875"

[GerhardH]

Today more investigation regarding timing.

First of all I believe that this distributor have no advanced stop pin and advance stop bushing by construction (stop is simply end of slot). Correction: No additional adfvance stop button, just the two main in the slots without bushings).

Second I believe that this distributor have not any kind of plastic wear buttons (the weights ride on the center plate directly).

Third I believe that the weights have a little bit of wear, but not serious, more or less still round.

Fourth I believe that the springs are absolutly to strong, see also measurements.

Measurement with vacuum pump on the vacuum advance canister:

Target:
AR23
START 5-7 inHg,
Max. advance distributor degree 7.5° (15 crank degree) , Max inHg 11-12.5.

Measured (initial timing is 10 crank degree)

07@10 7 inHg @ 10 crank degree
08@13
09@16
10@19
11@20
12@24
13@24
14@24
15@24

Means measurement meets target/specification.

Initial advance

Found out that I cannot advance more than 10° crank because the advance canister collide with the carburetor, have to change the plug wires on the distributor by 1 and check/adjust again. (By the way you need a 9/16 spanner)

Mechanical (centrifugal) advance. (vacuum advanced plugged)

Removed springs test advance = 50 crank degree at idle (as initial is 10 crank degree the distributor is able to advance by max. 40 degree), putted back the springs:

10@ 900
10@1000
11@1500
13@2000
14@2500
15@3000
16@3200

this is definitly not enough, wrong springs/weights what else need more material and investigation-

[GerhardH]

So back to the engine build. Happy to have cylinder head stands (Sealey VS1555.v2)

Heads are back from machine shop. Checked the surfaces and fitment (control by fine grinding with grinding paste)- ok

Valves from Manley inserted with a little bit grease on the stem.
Intake 2.020", 11/32 stem diameter, 4.880" length, #10650-8
Exhaust 1.600", 11/32 stem diameter, 4.910" length, # 10649-8

Than first measurements with the valve spring height micrometer 1.400 to 1.800 (SUM-900032), lost a couple of hours with wrong measurement because the valve retainer in my new kit is smaller in diameter than the stock one, therefore the retainer goes in the micrometer and the measurement was wrong.

Used Valve spring and retainer kit SUM-174001. (and this was wrong need SUM-174000 , see #146)

Some test measurement with the valve spring tester, found out difficulties to determine, the right shims,

[GerhardH]

Investigation which shim diameter I need?

[GerhardH]

Lesson learned :
Do not use wrong spring retainer (not keeper) for measurement!
Found out wrong kit ordered : need SUM-174000 for 0.344" stem diameter instead 0.307 " stem diameter. Slip of the pen-expensive-hurt

[GerhardH]

Still struggle with the shims. In the meantime I prepared the first turning of my engine after 60 years. Result: Without issues, perfect.

Changed the oil filter adapter to SUMMIT SME-2015
USED a melling oil pump SUMMIT SES-3-60-08-005 (Melling M-55A)
Oil pan SUMMIT SUM-G3500P
Dip stick SUMMIT PRO-66116
Oil pan gasket is from gasket set SUMMIT FEL-PRO 260-1000AT
Oil filter is MANN FILTER W 936/5

[GerhardH]

Later I will think about the pressure. Should I take the high pressure or modify to stock pressure with the additional spring in the package. My tendency is going to stock.

Lesson learned:
Is not possible to install the oil pump shaft from TOP. Ok disassembled the oil pan again, its all training.

If you preoil the engine the oil is coming out heavily on the connection for the oil pressure gauge- closed with a screw

[cornerstone]

I remember building my first engine Gerhard. It was a rewarding experience for a teenager. I made several mistakes but still really enjoyed it. All of your experience from former jobs as a machinist have given you a strong understanding of the exact tolerances required to do the job right. That American engine will run better than new... now it has German engineering as well!!

[GerhardH]

Hopefully it will run !!!