Autpometer gauge install... some info and a few questions

[84 400]

Okay I did this swap over the weekend. It is pretty easy and nothing to be afraid of. Just take your time and do things right.

First some questions...
1) I put these in a 1977 K10 with a th350 automatic and np205 transfer case. Does anyone have a part number to a speedo cable that will work for this application?
2) Before doing the swap my Water temp never got above 180 on the factory gauge. On the auto meter gauge it has read as high as 210 and normally goes down to 180. I have a 180 degree T stat in the truck. Is something wrong or is this a safe operating temp?

Important notes:
-Make sure that you use removable connectors or a bulk connector if you ever want to be able to remove the dash.
-Be careful how you route the wires
-A 73 to 1979 dash bezel is not the same as the 81 and up models. The 81 and up will not fit!!!!! right with the older style dash pad

Okay and now the best info that will make your swap easier then mine was..

For all trucks there will be a bulk connector that is labeled with 18 ports. 73-76 used different color wires and different wire locations then 77 and up trucks. Since my truck was built in 77 it actually used a 1976 harness which there is no info on the internet about.

1973-1976,77
1. Light Green - High beam
2. Gray - Instrument cluster lights
3. Black - Ground
4. Pink - Power when ignition on
5. Pink - Power when ignition on
6. Tan/ White Stripe - Parking brake (jumper to 17)
7. Tan - Fuel sender (jumper to 18)
8. Dark Green - Water temp
9. Black - Ground
10. Light Blue - L turn signal
11. Dark Blue - R turn signal
12. Pink - Power when ignition on
13. Empty
14. Empty
15. Black - Ground
16. Pink W/ Stripe - brake warning light
17. Tan/ White Stripe - Parking brake (jumper to 6)
18. Tan - Fuel sender (jumper to 7)

Keep in mind my truck does not have an electric choke nor does it have a "fasten seat belt light" It did have a separate 2 wire bulb for the "4wheel drive lock " light but since I installed a different transfer case and twin sticks this wire was disregarded.

On 77 to 87 models:
1. Light Green - High beam
2. Gray - Instrument cluster lights
3. Black - Ground
4. Pink/ Black Stripe - Power when ignition on
5. Tan - Oil sending unit
6. Pink/ Black Stripe - Power when ignition on
7. Pink - Fuel sender (jumper to 18)
8. Black - Ground
9. Dark Green - Water temp
10. Black - Ground
11. Light Blue - L turn signal
12. Dark Blue - R turn signal
13. Empty
14. Yellow - Fasten seat belt
15. Medium Blue - Choke
16. Pink/ Black Stripe - Power when ignition on
17. Tan/ White Stripe - Parking brake
18. Pink - Fuel sender (jumper to 7)

I did not have a dash harness out of a TBI truck (1987) so I do not know how that would vary if it all.

Hope this helps!

Other good sources:
http://www.73-87.com/7387garage/inte...ge_surface.htm
http://www.73-87.com/7387garage/inte...s_recessed.htm

I used a smaller speedo and tach then most and mounted them to the factory brackets. This eliminates the angle issues others have by surface mounting but it does not look as clean. As mentioned above I have no finished pictures because I need to cut my stock dash bezel to fit the four 2 and 5/8 and install it. The 82 dash bezel i used would not mount to my older style dash pad. The 3 led's on the top are for (p brake, high beam, and brake pressure). For turn signals I went to radio shack and found some larger LED's that pushed securely into the arrows from the back side.



The fuel gauge is pegged in both pictures because my sender got messed up offroading.

[3r!c84]

the fuel gauge problem is it has a short some where in the system

[84 400]

Originally Posted by 3r!c84

the fuel gauge problem is it has a short some where in the system

In that case i need to trace some wires. Thanks for the tip. The gauge will read lower when gas level drops. thats why i thought the sender got messed up from all the bouncing and slams it has been through off road. then again it does have a ****ty splice down by the tank...

[motornut]

if the sending unit is shorted to ground it goes empty,no connection to sending unit does that

[Orange77]

what if the unit reads almost half when the tank is full and goes down from there and sometimes spikes up like its working then goes back?

[84 400]

Originally Posted by motornut

if the sending unit is shorted to ground it goes empty,no connection to sending unit does that

SO your saying it is a open sending wire? It is strange the tank always worked great until One offloading trip when it mysteriously stopped. The only wiring issue is one splice . Aside from that the only other option is the sender itself. Do i have this right? As can be seen the original gauge was reading way over full before I did the swap.

[motornut]

seems like open
in high school,everyone wanted a drive home,i had a switch under the dash that grounded out the sending unit(72 ventura)
get a few bucks from the ppl go to get gas.click the switch after the car was off,pump get back in and you got gas.
thats why i think it's open lol

[3r!c84]

Originally Posted by motornut

seems like open
in high school,everyone wanted a drive home,i had a switch under the dash that grounded out the sending unit(72 ventura)
get a few bucks from the ppl go to get gas.click the switch after the car was off,pump get back in and you got gas.
thats why i think it's open lol

HAHAHA

smart man

[MTCK]

There is a wire from the sender to ground at the tank. If that connection is open you will get the 3 oclock reading.