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-   -   Anyone recognise this cable? (https://67-72chevytrucks.com/vboard/showthread.php?t=843600)

Belsh 04-07-2023 01:53 PM

Anyone recognise this cable?
 
4 Attachment(s)
So today I've had my first chance to get a good look over the truck and it seems its been cobbled together to sell! Ive found 3 things so far that I'm not sure of hoping you guys can help me out

First 2 pics this cable is connected into the trans casing and the other end is loose in the engine bay. Can anyone tell me what it is?

Also in the third picture is what looks like some sort of vaccum chamber and next to it a pipe with rubber connector on the end. Any ideas?

Then finally in the last pic this was finger tight so I've nipped it up with some grips, is that correct? Be good to know what it is also, I'm new to the mechanics of big american engineering just incase thats not already obvious :dum:

Grumpy old man 04-07-2023 02:03 PM

Re: Anyone recognise this cable?
 
The vacumm canister should be attached to the hose in the picture . It's a modulator valve, The transmission vacuum modulator valve determines how much load is on the engine so the transmission can shift properly. It has a vacuum line that connects to the intake and measures the amount of vacuum in the engine. the forth picture is the speedometer cable , it should be snug so it does'nt leak ,

geezer#99 04-07-2023 03:00 PM

Re: Anyone recognise this cable?
 
That’s not a tv cable grumpy.
That’s a detent cable (kick down) for a turbo 350.

Another thing I see in your pics.
The rad fan you have.
They are well known to blow apart.
Best to find a better one.

Grumpy old man 04-07-2023 03:10 PM

Re: Anyone recognise this cable?
 
Quote:

Originally Posted by geezer#99 (Post 9194409)
That’s not a tv cable grumpy.
That’s a detent cable (kick down) for a turbo 350.

Another thing I see in your pics.
The rad fan you have.
They are well known to blow apart.
Best to find a better one.

Good eye ! :chevy:

Belsh 04-07-2023 03:17 PM

Re: Anyone recognise this cable?
 
Many thanks for that Grumpy, I've got a whole lot to learn!!

Belsh 04-07-2023 03:21 PM

Re: Anyone recognise this cable?
 
Thanks Geezer, shame about the fan as its just about the only new bit on the truck but I dont fancy it exploding on me so I will get that changed!

Where does the other end of the detent cable attach to? Thanks

geezer#99 04-07-2023 03:37 PM

Re: Anyone recognise this cable?
 
To a bracket beside the carb on the drivers side.
Take a pic of your carb. Both sides and the front.
Also a better pic of your engine compartment might help find other problems.

Belsh 04-07-2023 03:58 PM

Re: Anyone recognise this cable?
 
Thanks for your help Geezer, I'll take some pics in the morning and get them posted

HotWheelsFan 04-07-2023 04:55 PM

Re: Anyone recognise this cable?
 
Not to point out a correction, or step on other's responses :)

Speedo cable leaks come from bad seals... It should not leak, even if you remove or unscrew the speedo cable.


You have the correct forum for learning, and I share your sentiments. I love the information here.

Bob

Rust_never_sleeps 04-07-2023 07:31 PM

Re: Anyone recognise this cable?
 
1 Attachment(s)
Here's how the TH350 kickdown cable attaches on the driver's side of mine, with just a washer and a snapring(or perhaps "circlip" in the UK). Throttle rod is in the foreground attached at the left. Yours may not look like this, but the link to the tranny cable will be similar

ghackett1 04-08-2023 09:54 AM

Re: Anyone recognise this cable?
 
You also need a new tranny mount. Yours appears to be cracked.

Belsh 04-08-2023 01:16 PM

Re: Anyone recognise this cable?
 
5 Attachment(s)
Hi Geezer, I've attached pics of carb and engine bay, looks to me like i will need a bracket to support the detent cable to the carb?

Belsh 04-08-2023 01:19 PM

Re: Anyone recognise this cable?
 
Quote:

Originally Posted by ghackett1 (Post 9194610)
You also need a new tranny mount. Yours appears to be cracked.

Crikey yes I can see that now you say, you've a very keen eye!! Thanks

geezer#99 04-08-2023 03:09 PM

Re: Anyone recognise this cable?
 
Nice pics!
First off.
I’m wrong about your rad fan. Not the dreaded flex fan. That one is good.
Number two.
Here’s a link on your kick down bracket.


http://67-72chevytrucks.com/vboard/s...d.php?t=648493


Another safety hazard.
Move that fuel filter from above the headers.
Fuel line should be straight ahead and down in front of head.

Belsh 04-08-2023 03:35 PM

Re: Anyone recognise this cable?
 
Quote:

Originally Posted by geezer#99 (Post 9194686)
Nice pics!
First off.
I’m wrong about your rad fan. Not the dreaded flex fan. That one is good.
Number two.
Here’s a link on your kick down bracket.


http://67-72chevytrucks.com/vboard/s...d.php?t=648493


Another safety hazard.
Move that fuel filter from above the headers.
Fuel line should be straight ahead and down in front of head.

Thanks Geezer, your help is greatly appreciated

BROWN 70 04-08-2023 06:21 PM

Re: Anyone recognise this cable?
 
hi, looks like you need the edelbrock bushing in the thottle linkage connection. I had to help a buddy fix his on a 57 nomad. otherwise the throttle is very sloppy. good luck, chuck

yuccales 04-08-2023 07:50 PM

Re: Anyone recognise this cable?
 
Quote:

Originally Posted by Belsh (Post 9194665)
looks to me like i will need a bracket to support the detent cable to the carb?

Unless my eyes are fooling me, in your last picture I think your throttle return spring is hooked up to the bracket?

BROWN 70 04-08-2023 09:16 PM

Re: Anyone recognise this cable?
 
x2 post 17

Accelo 04-09-2023 01:01 AM

Re: Anyone recognise this cable?
 
Post 10 is the early cable end. The 1969 through 70 style. I believe it changed n 71.
If he can find the other end of the cable take a picture and I can identify the end type.
Clearly shows the later style bracket in the picture (1971 -up). You are also missing the stud where the cable/or slide/ attaches to the carburetor. If you can get it back to the way it was engineered the transmission should shift down like it was designed. You will need the vacuum line connected. It is more important to the function of the transmission than the kick down cable.

'68OrangeSunshine 04-09-2023 01:13 AM

Re: Anyone recognise this cable?
 
Mr Belsh, you appear to have looped the two vacuum ports on your AFB-type carburetor together.
The vacuum port on the passenger side should be connected to the vacuum hose from the distributor vacuum canister output. The one on the drivers side should be capped -- except when connected to an external Vacuum Gauge when doing a tune up.

And the speedo cable connectors on both ends should only be a firm finger tight. I'll use pliers to loosen them if they're stuck, but one shouldn't need to crank it.

'68OrangeSunshine 04-09-2023 01:17 AM

Re: Anyone recognise this cable?
 
Quote:

Originally Posted by geezer#99 (Post 9194686)
Nice pics!
First off.
I’m wrong about your rad fan. Not the dreaded flex fan. That one is good.
Number two.
Here’s a link on your kick down bracket.


http://67-72chevytrucks.com/vboard/s...d.php?t=648493


Another safety hazard.
Move that fuel filter from above the headers.
Fuel line should be straight ahead and down in front of head.

Hey Geezer -- I like Flex Fans. The one on the 292 in my '68 C/10 Stepside was new in 1977 and it's still fine. I think I even have a lifetime warranty on it.

Belsh 04-09-2023 02:26 AM

Re: Anyone recognise this cable?
 
1 Attachment(s)
Quote:

Originally Posted by '68OrangeSunshine (Post 9194827)
Mr Belsh, you appear to have looped the two vacuum ports on your AFB-type carburetor together.
The vacuum port on the passenger side should be connected to the vacuum hose from the distributor vacuum canister output. The one on the drivers side should be capped -- except when connected to an external Vacuum Gauge when doing a tune up.

And the speedo cable connectors on both ends should only be a firm finger tight. I'll use pliers to loosen them if they're stuck, but one shouldn't need to crank it.

Hey 68, I've only just bought the truck and my experience of engines is limited thus I'm finding this place absolutely invaluable!! Sorry for the quality of my attached pic but does it show what you are saying about the connection from the carb to the distributor?

Also on the speedo connection can i get a new seal for the end of the cable into the tranny or do I just need a new cable? The speedo needle flickers badly when driving (like when youre doing 30 it bounces between 20 and 40 as an example) I havent had time to research it yet as getting it safe to drive is my first job!!

geezer#99 04-09-2023 08:51 AM

Re: Anyone recognise this cable?
 
Keep at it, making it safe.
Brakes and steering. Brakes being first on the list.

Here’s a link to the speedo housing leak you have. The housing has two o-rings. The bigger outside one which seals the housing to the tailshaft and the smaller inside one that seals the driven gear. Likely yours is the inside one leaking. Best to replace the complete unit like the one in the link.
Also the bouncy speedometer can be caused by old dried grease in the cable itself. The cure is removal of the inner cable and cleaning out the old grease and relubing.


https://www.classictransmissionsolut...ter-turbo-350/

Accelo 04-09-2023 10:26 AM

Re: Anyone recognise this cable?
 
The inner seal is an actual lip seal. Typically they leak because the lip runs on a plastic gear and wears a groove in the plastic shaft.
I have never seen the outer "O" ring leak. Replacing the seal and the gear will fix your leak. You will need the color or tooth count of the gear as they very by application. Only hand tighten the speedo cable to the adapter. It is not a sealing service and it will still leak no matter how tight you get it. I have even observed them with Teflon tape on the threads. Nope it didn't work.

Belsh 04-09-2023 12:36 PM

Re: Anyone recognise this cable?
 
1 Attachment(s)
Quote:

Originally Posted by geezer#99 (Post 9194868)
Keep at it, making it safe.
Brakes and steering. Brakes being first on the list.

Here’s a link to the speedo housing leak you have. The housing has two o-rings. The bigger outside one which seals the housing to the tailshaft and the smaller inside one that seals the driven gear. Likely yours is the inside one leaking. Best to replace the complete unit like the one in the link.
Also the bouncy speedometer can be caused by old dried grease in the cable itself. The cure is removal of the inner cable and cleaning out the old grease and relubing.


https://www.classictransmissionsolut...ter-turbo-350/

Thanks Geezer, I'll get that ordered up and I'll try your suggestion for the bouncy speedo whilst putting the new seals on.

As for brakes they're driving me up the wall, I know there's a problem with the front driver side as the drum is soaking inside but I just cant get the spacers off to get into it. Tried leverage and heat and neither working. Have ordered an impact driver so hoping that will do the trick!


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