The 1947 - Present Chevrolet & GMC Truck Message Board Network

The 1947 - Present Chevrolet & GMC Truck Message Board Network (https://67-72chevytrucks.com/vboard/index.php)
-   The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board (https://67-72chevytrucks.com/vboard/forumdisplay.php?f=4)
-   -   Restoring Rusty (https://67-72chevytrucks.com/vboard/showthread.php?t=645440)

69heavychevy 05-19-2015 10:50 PM

Re: Restoring Rusty
 
Could you post pics of your x pipe set up. I'm interested in doing a similar set up but concerned with clearance/routing issues. Thanks in advanced.

hatzie 05-20-2015 08:56 AM

Re: Restoring Rusty - Operation Tachometer
 
Quote:

Originally Posted by Titomars (Post 7175200)
yes it will. The gauge does not care how many tanks it is hooked through. The switching is at the tank selector switch.

The gauge is the same regardless of the number of tanks. I drew up a wiring diagram for someone that wanted to use three tanks. I believe it took 2 switches and 2 valves. :D

You may be interested to know... The basic damped air core movement is the same on all three small can gauges and for that matter the big fuel gauge. The parts that change are the bias resistor, bias resistor stud location, graphics, and faceplates. EXCEPT the 73-75 ammeter...
The small and large fuel gauges use the same bias resistor on the same studs.
You should be able to re-purpose one of the other gauges to fill the lower left hole using a set of gauge overlays and the correct bias resistor on the correct studs. It depends on whether you can find one of the three that has the correct mounting hole locations on the sheet metal face.

73-80 switch the sender through the dash switch.

81-91 use a motorized valve to switch the fuel flow. That valve has a switch to handle the gauge senders as well.

Gregski 05-20-2015 08:56 PM

Re: Restoring Rusty
 
3 Attachment(s)
the new printer circuit board arrived today from LMC truck $84 bucks delivered ~ expensive if you ax me, but we like to try and do things right before going Comando, meaning I considered wiring things up directly minus the circuit board, but decided we would make that our Plan B

special thanks to US Postal Service for putting in that air vent hole in the box to ensure this electronic component is properly ventilated - LOL

Gregski 05-20-2015 09:01 PM

Re: Restoring Rusty
 
1 Attachment(s)
and here they are side by side (ok top n bottom) for comparison, you get the idea

now keep in mind this is a comparison of the old '78 board and the new '78 board (my original '74 is still in the truck we will take a look at it later)

hatzie 05-21-2015 11:06 AM

Re: Restoring Rusty
 
They're performing black magic. Plating copper on plastic.
It's done with either metallic ink or vacuum deposition and a thermal laminator. Either way it's not easy and takes some pretty expensive specialized tools along with the skilled people to set em up.
$84 is pretty good.
How does the plate thickness at the contact connection points compare to the original GM part?

Gregski 05-21-2015 11:42 AM

Re: Restoring Rusty
 
Quote:

Originally Posted by hatzie (Post 7180510)
How does the plate thickness at the contact connection points compare to the original GM part?

Actually feels about the same, we'll see how well it works.

Gregski 05-21-2015 11:52 AM

Re: Restoring Rusty
 
1 Attachment(s)
dang it the local junk yards are having a 50% off sale yesterday and today but I'm not sure I'll be able to make it out there, sure could use a better radiator support

Chrispbrown36 05-21-2015 12:48 PM

Re: Restoring Rusty
 
Sweet jesus! Can ya pick me up a windshield?

Gregski 05-21-2015 01:24 PM

Re: Restoring Rusty
 
Quote:

Originally Posted by Chrispbrown36 (Post 7180645)
Sweet jesus! Can ya pick me up a windshield?

how much are they where you're at?

enaberif 05-21-2015 01:31 PM

Re: Restoring Rusty
 
Quote:

Originally Posted by Gregski (Post 7180563)
dang it the local junk yards are having a 50% off sale yesterday and today but I'm not sure I'll be able to make it out there, sure could use a better radiator support

To show our appreciation we are holding a TWO DAY Toolkit Members ONLY 50% OFF SALE on all parts pulled from the yard, this Wednesday, May 20th - Thursday, May 21st. The General Public Sale runs Friday-Monday, May 22nd through May 25th.

Still have a sale the other days :)

Gregski 05-21-2015 01:34 PM

Re: Restoring Rusty
 
5 Attachment(s)
picked up a couple of these plastic storage bin organizer thingies from Harbor Freight, they are normally $14 bucks but I found a coupon for $6, now I gave up on Harbor Freight tools a while back but I figure they can't screw up plastic bins too much, LOL

now maybe you can relate, I struggle organizing car bits, like fuses, washers, butt connectors, light bulbs (why do they insist on selling us two when all we need is one) nuts and bolts, cotter pins, etc, it seems like every little thing needs their special nook to live in, so there you go

also from time to time I just stand in the middle of my Temple (some call it a Garage others a Workshop) and I say why can't I find the altar, where did all this junk come from, where am I to rest by beer

and I take a moment and I try once again to get re-reorganized

Gregski 05-21-2015 01:42 PM

Re: Restoring Rusty - Engine Bay Pics
 
5 Attachment(s)
mounted the driver side inner fender today and figure I'll share a few most recent pictures (yes I said pictures and not pics, I speak 40+ year old, LOL) of the engine bay, with the inner fender and them purdy (for a while at least) long tube headers, oh and the painted frame rail

not back for a blond Pollack if I do say so myself, but we're not there yet...

Gregski 05-21-2015 01:45 PM

Re: Restoring Rusty - Engine Bay Comparison @ 8 months
 
2 Attachment(s)
what's that? Show us the original how we got it out of the barn from the church lady, so we can Stare 'N' Compare

here we go...

greg64 05-21-2015 02:15 PM

Re: Restoring Rusty
 
Wow, Greg, what a difference! Those inner fenders look great, considering the low-buck approach you took with them. Radiator core support next?

Gregski 05-21-2015 04:07 PM

Re: Restoring Rusty
 
Quote:

Originally Posted by greg64 (Post 7180750)
Wow, Greg, what a difference! Those inner fenders look great, considering the low-buck approach you took with them.

Thank you bud, low buck / high pride type a thing.

Quote:

Originally Posted by greg64 (Post 7180750)
Radiator core support next?

I think the bed will be next, going to take off the old one and drop in a new(er) floor

Gregski 05-21-2015 04:23 PM

Re: Restoring Rusty
 
5 Attachment(s)
Quote:

Originally Posted by 69heavychevy (Post 7178949)
Could you post pics of your x pipe set up. I'm interested in doing a similar set up but concerned with clearance/routing issues. Thanks in advanced.

Not sure if you find these helpful, it was pretty difficult to take them laying on my back and all (too lazy to jack up the truck) also I know the U brackets should point up instead of down so they don't catch on anything, and I had them like that the first time, and the second and third time, but after 74 adjustments I just left them where they wanted to hang, LOL

also please take my word for it that these pipes are fairly even and at the same height, it's these camera angles that make them look like Stevie Wonder did the install for me

Gregski 05-21-2015 04:43 PM

Re: Restoring Rusty
 
1 Attachment(s)
A SUPER RARE SITE... a clean workbench!

~Approach with Caution ~

enaberif 05-21-2015 04:58 PM

Re: Restoring Rusty
 
Quote:

Originally Posted by Gregski (Post 7180879)
A SUPER RARE SITE... a clean workbench!

~Approach with Caution ~

Mastercraft workbench at its finest!

Gregski 05-21-2015 05:22 PM

Re: Restoring Rusty - Work Bench
 
1 Attachment(s)
that's more like it...

Gregski 05-21-2015 05:28 PM

Re: Restoring Rusty
 
3 Attachment(s)
and so operation Tach You're It commences

there are three things to carefully disconnect before removing the gauge cluster

1. disconnect the mechanical speedo cable (cable looks and feels like the brake cables on your old 10 speed bicycle)

2. disconnect the mechanical oil pressure gauge by unscrewing a metal tube from the back, first undo the three screws that hold the gauge and pull it forward a bit (why it's called mechanical I don't know, it should be called hydraulic)

3, disconnect the thin ribbon cable that goes to one of the light bulbs, it may be an additional ground strap

Gregski 05-21-2015 05:34 PM

Re: Restoring Rusty
 
2 Attachment(s)
then we are left with some ugly cobra looking wiring harness

which for all intensive purposes we must study and learn, so here is the front side of the connector Pins #1 through #9 and their respected colored wires, we shall call this poor man wiring diagram side Uno

Gregski 05-21-2015 05:52 PM

Re: Restoring Rusty - Gauge Cluster Connection
 
1 Attachment(s)
ok lets check out the other side, here are Pins #10 - #18

Gregski 05-21-2015 05:54 PM

Re: Restoring Rusty
 
1 Attachment(s)
ok, so far so good, but here's where it gets interesting, I noticed that three wires loop from one side to the other, so wrap your mind around that for a minute

looks like the pink wire, the tan wire, and the tan/black wire are playing both sides (politicians are they)

Gregski 05-21-2015 06:40 PM

Re: Restoring Rusty
 
1 Attachment(s)
ok folks put on your detective hats because we have a situation, there is a lonely loose black wire it disappears into the wiring harness and appears to be headed towards the cluster connector, we must track it down

Gregski 05-21-2015 07:21 PM

Re: Restoring Rusty
 
ok, it appears the black mystery wire splices into another black wire that plugs in to Pin # 9 ie Ground, fair enuff, now we need to figure out where it was headed the other direction does it go to the fuse box, or screw into the dash somewhere?

enaberif 05-21-2015 07:51 PM

Re: Restoring Rusty
 
Are those the black wires for your ammeter that run from under the hood? Run a test with your voltmeter to test.

Gregski 05-21-2015 07:59 PM

Re: Restoring Rusty - Oil Pressure Gauge Upgrade
 
3 Attachment(s)
so one of the side perks of upgrading to a 1978 gauge cluster is that it has the electronic oil pressure gauge, so out with the old mechanical one first

the mechanical setup has a metal tube that runs from the back of the engine block under the distributor by the firewall and into the cab, and connects to the back of the mechanical oil pressure gauge, yes oil goes way up there into your dash and could possibly spray you in the face @ 60 PSI awesome - NOT!

motornut 05-21-2015 09:03 PM

Re: Restoring Rusty
 
Maybe the black could be seat belts ?
Among everything else grounded they usually went down to one wire about a foot from the cluster plug in

Gregski 05-21-2015 09:42 PM

Re: Restoring Rusty
 
2 Attachment(s)
alright so had to go out and buy an oil pressure sending unit, they come in two flavors cheap (ie $8.00) and the one I need ($36.00)

cheap = idiot light

expensive = with a gauge

Pretty much right off the bat I knew we were going to have a fitment issue, this thing is just too tall and bulky to fit under the HEI distributor, any of you wan to share pics of your electronic sending units? that would be much appreciated

enaberif 05-21-2015 09:52 PM

Re: Restoring Rusty
 
You need to get a 45 degree fitting with a 1/4 npt male to I think a 1/4 female of you have room behind the intake otherwise you will need a 1/4 nipple to 45 female/female.

motornut 05-21-2015 10:00 PM

Re: Restoring Rusty
 
2 Attachment(s)
yup i used an extender too

Gregski 05-21-2015 11:09 PM

Re: Restoring Rusty
 
2 Attachment(s)
Quote:

Originally Posted by enaberif (Post 7181217)
You need to get a 45 degree fitting with a 1/4 npt male to I think a 1/4 female of you have room behind the intake otherwise you will need a 1/4 nipple to 45 female/female.

you my friend are a gentleman and a scholar, I picked up just what you said, and ended up going with the 1/4 nipple (ie riser) to the 45 female/female elbow

problem = solved

thank you so much

Gregski 05-21-2015 11:10 PM

Re: Restoring Rusty
 
Quote:

Originally Posted by motornut (Post 7181227)
yup i used an extender too

dang them is fancy, I like those risers, and thanks for the pic of your [ahem] unit... sender unit, sender unit

Gregski 05-21-2015 11:14 PM

Re: Restoring Rusty
 
3 Attachment(s)
time to compare the 1974 Mechanical Oil Gauge to the Electronic Oil Gauge circa 1978

note no wired plug into the mechanical one, just one hollow metal tube, on the other hand the electric one has three wires going to it

the take away here is that the electronic gauge is only half the battle, it's useless by itself, you cant just wire it up and get results, it is the sending unit behind the scenes feeding it all the pertinent information, ie doing all the heavy lifting

Gregski 05-21-2015 11:33 PM

Re: Restoring Rusty - Oil Gauge Test
 
1 Attachment(s)
next it was time to test the Electric Oil Pressure gauge

here's how I do it

I set it on the battery and connect the negative stud (bottom most) to the negative battery terminal directly with a black wire with aligator clips on either end

I connect the positive stud to the positive battery terminal directly with a red wire with aligator clips on either end

Then I connect the third stud to the oil pressure sending unit directly

I make these direct connections on purpose, this is to eliminate any wire harness problems such as shorts or broken connections, as well as any bad fuses, keep in mind this is a gauge test and a gauge test only, we are not testing the entire circuit here

the goal is to keep it simple

Gregski 05-21-2015 11:38 PM

Re: Restoring Rusty - Tachometer Test
 
2 Attachment(s)
I test the Tachometer in the same / similar way

put the Tach on the battery

the Tach's blade terminals on the back are labeled, thank god, we have a positive, negative, and coil

so we aligator clip positive to battery positive

aligator clip negative to battery negative

and [wait for it] connect the coil terminal to the left terminal on the HEI distributor I think it says Tach on it, the other one is Ignition or power something like that

But I think we might could have a problem, I used my trusty (I love the darn thing) digital timing light to stare and compare the Tachometer reading to its reading, and I think we is a bit off, LOL

Gregski 05-21-2015 11:42 PM

Re: Restoring Rusty
 
A Take Away Lesson Learned so far people, and we all may appreciate this, it appears that it don't matter where the needle rests on the gauge when it is unplugged, like for example on them eBay pictures you are staring at going is that Tach jacked why is the needle resting on 15, or why is that oil pressure gauge needle in the middle of that gauge on this guys table at the swap meet, what I noticed is as soon as I send juice to it, by connecting the gauge to the battery, both positive and negative, the gauges 0 zero themselves out

enaberif 05-22-2015 12:18 AM

Re: Restoring Rusty
 
Does that gun do 8 cylinders? I only see 2 and 4 on the panel? Could be why its reading weird?

Gregski 05-22-2015 12:25 AM

Re: Restoring Rusty
 
Quote:

Originally Posted by enaberif (Post 7181414)
Does that gun do 8 cylinders? I only see 2 and 4 on the panel? Could be why its reading weird?

I think that's 2 stroke 4 stroke

enaberif 05-22-2015 12:27 AM

Re: Restoring Rusty
 
I thought 2 cycle and 2 stroke were the same thing.


All times are GMT -4. The time now is 05:51 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2023, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com