Need help, speedometer doesnt work..

[oldblue1968chevy]

3 spd on the column, 3 hole guage cluster/stock guages.

When I bought the truck it was working, after I bought it I was crawling around under it and noticed PO or someone may've cross threaded the speedo cable. Anyway it worked so I didnt mess with it.

Fast forward-I pulled motor/tran for a 350 out of a 72 GMC. Swapped em out cleaned and painted stuff and ever since it hasnt worked.

Do I need a new cable? I was under there earlier undid the cable put it back on etc, backed truck out of garage and Needle still stayed at 0.

Thank you

[oldblue1968chevy]

Actually, I just lied to you guys, It worked for about 50 miles after I got everything back together, THEN it quit.

Thanks

[67chevy1series]

hahahah your funny it did that after 50 miles lol

[oldblue1968chevy]

Anyone besides rick?

Lol just kidding But really any ideas what it would be?

[Maxxd07]

I believe they have a little "key" in them and if that wore out you may have problems. Unhook the cable on tranny and spin it while someone looks at the gauge seeing if it works.

[AirSpeed]

Disconnect the cable from the speedo and go for a drive, check to see ifthee cable is turning, you may need to push it in a little to make sure it's engaged at the other end, if it's not turning you may have stripped the square socket that the cable sits in in the tranny. On my 69 granny four speed I have an adapter that mounts to the tranny, it has the same problem, the little square socket was stripped. I cleaned it out and filled it with some JB weld then pushed the cable in, when it hardened it formed a square socket again and lasted 15 years.
If the cables turning check the socket in the speedo to see if it's worn, you should be able to spin the speedo by hand to make sure it's working.
Posted via Mobile Device

[oldblue1968chevy]

^ Thanks i'll have the GF of lil sis watch the guage while I spin it (from trans side)

What could break? Would it be bad if the lil thing on the inside of the cable came out a few inches? (It did when I had it off, i shoved it back in )

[oldblue1968chevy]

Thanks! I"ll try this all tomorow

Is the 'stripped thing' fixable without jb weld lol I"ll letchall know the results tom. evening! Thanks!!!!!!!

[AirSpeed]

[QUOTE=oldblue1968chevy;4414153]Thanks! I"ll try this all tomorow

Is the 'stripped thing' fixable without jb weld
Yes, you could buy a new gear, that's what the cable slides in to, it's made out of nylon, you can get a new one from "ClassicParts", you will need to count the teeth on yours in order to get the right one.
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[oldblue1968chevy]

OK, A very kind member sent me his old speedo cable (he went LS). My cable was broken in half (inner).

Well, I took it apart,cleaned and lubed it, and got it instaleld on my truck today, Hooked up to speedo end and turned with my fingers, It worked! So I hooked it to trans and backed truck up and went forwards, nothing.

I took the little barrel shaped thing out of trans (loosened 7/16 bolt) and took the barrel out, trans fluid came out so I shoved it back in and came inside.

Tomorow I'll double check everything (Unplug from dash, and see if its moving, and unplug from trans and spin via finger to see if its moving) I cant wait till this is fixed, I can calculate mileage/when to change oil better.

Thanks

[oldblue1968chevy]

Okayy..

I went out in the cold and sat in the truck with heater running..

I unscrewed the cable from the back of speedo, and drove the truck, the cable turned!

So, my theroy is..That the cable isnt engaging @ both ends (I can spin speedo needle from trans end, and the cable turns @ guage end.

So what can I do to get it to engage @ both ends?

Thanks!

[67chevy1series]

buy a speedometer rebuild kit a company called ''help'' makes it i have one but you need the old one to rebuild and i dont have the old one

[oldblue1968chevy]

Well,I think its all working fine, its just not connecting on BOTH ends, only 1 at a time..

I'll play again tomorow

[67chevy1series]

ok sounds good

[AirSpeed]

Are you maybe cross threading the connection behind the speedo and not getting the cable to seat all the way? Its easy to do when reaching up behind the dash! Maybe your cable is to short, I know some of those rebuild kits reqiure that you cut the cable to length and crimp a new end onto it, maybe your cable is a little to short? I can't imagine what else could be wrong.
Posted via Mobile Device

[oldblue1968chevy]

Its a 'used' cable from a fellow member..

I dont think its crossthreaded but could be, but it turns the needle if i roll it with my fingers under the truck..

[CUSHE63]

Ours didn't work when we got it (350, auto trans).. the po gave us another cluster and cable... When I took the cable off the tranny, I looked in the hole and didn't see the plastic gear on the trans shaft. When we removed the engine/trans, I removed the nose cone and saw that the clip that holds the gear in place was broken and the gear was moved forward not making contact with the drive gear....tha is why it didn't work.

Steve

[AirSpeed]

Originally Posted by oldblue1968chevy

Its a 'used' cable from a fellow member..

I dont think its crossthreaded but could be, but it turns the needle if i roll it with my fingers under the truck..

I would check both ends and make sure they are threading all the way in. Does the cable you have have a crimped on piece at one end? Or does the cable itself have the pressed square shape? If it's one that has the crimped on end, the other guy may have cut it a little short, his housing could be a little longer than yours, if it's just a little short it could keep it from engaging.
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[oldblue1968chevy]

Its a plastic rubber style.

The trans end is good and speedo end is good (good/working)

Its just not engaging @ both ends..

[AirSpeed]

Originally Posted by oldblue1968chevy

Its a plastic rubber style.

The trans end is good and speedo end is good (good/working)

Its just not engaging @ both ends..

The inner cable has plastic ends? I've never seen one of those. I bet it's just to short and when the outer sleeve is attached, only one end of the inner cable is engaging. You can get a new, universal inner cable at any parts store for about $5-$10, it might be worth just getting a new one.
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[oldblue1968chevy]

No no no, the outer cable (cover) is plastic or rubber (not like the one that came off the truck that was metal)

I may have to get a new one, any idea how much should be sticking out at both ends?

[oldblue1968chevy]

It works, I wasnt going fast enough to test it I guess

New cable=solved problem!

Thanks USMCCHEVY FOR THE CABLE!!!

[usmcchevy]

Originally Posted by oldblue1968chevy

It works, I wasnt going fast enough to test it I guess

New cable=solved problem!

Thanks USMCCHEVY FOR THE CABLE!!!

No problem man!