Author Topic: DIY throttle cable questions  (Read 23880 times)

Offline txchainsawgogi

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DIY throttle cable questions
« on: February 04, 2012, 07:21:44 pm »
so, just replaced the carb in my 78 350 5.7L and man what a difference. i had rebuilt the original but felt like there was still something i had missed. it runs the best it has in probably a decade BUT now i've got a new problem. having installed a small throttle body spacer and lifting the carb ALMOST one inch, the old worn out throttle cable doesnt like being in a new position.

the plastic housing is literally rock hard and has no give to it, so when i raise it(even just slightly) it binds some where inside. i've tried lubing it but the lube never reaches the other end. i figure its gotta have some crap stuck in it. it also looks like its got atleast 5-6 inches of extra cable/housing coming out of the firewall.

short of just replacing it with a universal-cut-to-fit cable, can i just cut some of the slack and straighten out the line, then RE-CRIMP the little eyelet that hooks to the throttle arm? seems like that should be fine.

anyone ever have to do this? also…why would my cable be so frickin' long? im sure its stock.

Offline bd

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Re: DIY throttle cable questions
« Reply #1 on: February 04, 2012, 07:45:31 pm »
so, just replaced the carb in my 78 350 5.7L and man what a difference. i had rebuilt the original but felt like there was still something i had missed. it runs the best it has in probably a decade....

It's always rewarding when changing a component yields a big improvement!   :D

Quote
  ...why would my cable be so frickin' long?  im sure its stock.

If your talking about the 4-6" loop the cable makes between the firewall and the engine bracket, that's there to allow for engine movement.  Otherwise, engine lift might stretch the cable too tight or cause unexpected acceleration.  It also makes it easier to align the cable to the bracket.
Rich
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Offline txchainsawgogi

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Re: DIY throttle cable questions
« Reply #2 on: February 04, 2012, 07:52:45 pm »
but now that its literally rock hard…do you think i should replace it, or take SOME of the play out?

Offline bd

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Re: DIY throttle cable questions
« Reply #3 on: February 04, 2012, 08:21:19 pm »
To quote Bake74:  "The easiest and most obvious solution to any problem is 99% of the time correct."

From my perspective, you're asking kind of a subjective thing.  So as to better understand your problem, can you post a pic?  In the meantime, try working a good penetrating oil (like PB Blaster) into the cable housing, followed by a little TriFlo.  A little compressed air might help you work it all the way through.  "Rock hard" sounds like your existing cable is beyond using a heat gun to soften the plastic enough to reshape it w/o it breaking.

If the preceding ideas fail, have you exhausted your local sources for a NOS original cable?  Get a P/N from a GM dealer and then have them run it through their dealer parts locator system.  I just picked up an obsolete crossmember this way.  I would try to stay with an original cable if possible.
Rich
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In other words... if people learn by making mistakes, by now I should know just about everything!!!
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Offline txchainsawgogi

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Re: DIY throttle cable questions
« Reply #4 on: February 04, 2012, 08:35:06 pm »
i would look into OE replacements if my truck werent my daily driver. it is weird though how the sleeve got so aged and hard that now, moving it anywhere other than where it was causes binding. i'll try again in the morning to work some penetrant down the line but… a universal replacement might have to do.

Offline bd

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Re: DIY throttle cable questions
« Reply #5 on: February 04, 2012, 08:40:10 pm »
If penetrant doesn't resolve it, post your VIN w/o the last six digits (or PM me) and I'll try to find an OE P/N for you next week.  Best of luck!
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
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Offline timthescarrd

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Re: DIY throttle cable questions
« Reply #6 on: February 04, 2012, 09:35:45 pm »
I bought a new throttle cable for my 84 from o'rielly's direct OE-sytle replacement, ran about 16 bucks if i remember right. been runnin solid for 7 months now

Offline Donut

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Re: DIY throttle cable questions
« Reply #7 on: February 05, 2012, 08:38:40 am »
imo, replace it.  I wouldn't expect a 30+yr old cable to be welcome to change.
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Offline Blazin

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Re: DIY throttle cable questions
« Reply #8 on: February 05, 2012, 09:58:36 am »
I got one from NAPA about a year ago for my 86 K2500, and just picked one up a few weeks ago from Auto Zone for my buddies 85 C10. Niether one broke a $21 dollar bill.
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Offline bake74

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Re: DIY throttle cable questions
« Reply #9 on: February 05, 2012, 10:44:12 am »
but now that its literally rock hard…do you think i should replace it, or take SOME of the play out?

     If it is rock hard like you said, no matter what you do it will not soften back up, only break and crack all over.  For now you could cut end off like you said, remove some of the plastic and mount where you want.
    You could maybe take all the old plastic off and replace it with new plastic if you have the means.  If not you can do what I said above and order a new one and put on when you get it for safety reasons if not for anything else.
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Offline roger97338

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Re: DIY throttle cable questions
« Reply #10 on: February 07, 2012, 04:43:26 pm »
I went with a universal Lokar throttle cable for my truck. Follow the directions that come with it, and everything will work out perfectly.

Offline txchainsawgogi

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Re: DIY throttle cable questions
« Reply #11 on: February 07, 2012, 09:02:31 pm »
i got it out and replaced in a few minutes. muuuuch smoother now. that combined with new return springs and my pedal feels NEW again.

Offline bd

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Re: DIY throttle cable questions
« Reply #12 on: February 07, 2012, 10:09:47 pm »
Glad to hear you got it fixed and working right.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline beastie_3

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Re: DIY throttle cable questions
« Reply #13 on: February 07, 2012, 11:13:08 pm »

If your talking about the 4-6" loop the cable makes between the firewall and the engine bracket, that's there to allow for engine movement.  Otherwise, engine lift might stretch the cable too tight or cause unexpected acceleration. 

Engine movement haha. I did a brake stand once in my 66 mustang with a inline 200 and a motor mount broke. When the engine rotated, it pulled the throttle cable and i had to put it in N  to level it out. Luckily I was only a few blocks away. Kids!

Offline timthescarrd

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Re: DIY throttle cable questions
« Reply #14 on: February 08, 2012, 09:26:30 am »
Engine movement haha. I did a brake stand once in my 66 mustang with a inline 200 and a motor mount broke. When the engine rotated, it pulled the throttle cable and i had to put it in N  to level it out. Luckily I was only a few blocks away. Kids!

That's because you were in a ford :P