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1977 : Diagnosis?

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Old Jul 7, 2014 | 03:06 AM
  #1  
Giant_Robot's Avatar
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Default 1977 : Diagnosis?

Hi everyone has been helpful sofar in these forums, I have a 1977 coupe project here:

Engine block has these numbers stamped on it: 8 6 - 4 2 passenger, 328249 7 GM, 1 3 - 5 7 driver, firing order 18436572, 3638 stamped light upfront on passenger side.

Unsure if it is original #'s matching or not, assuming not, would just like to know what it is exactlty. not concerned with being original parts or resell value at all just want it to run well.

here is the current engine setup, some of you may have already seen the fuel filter on the passenger side outside the frame. Here is some more photos to show you what im working with.

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overview of all my issues:
speedometer/odometer not working.
some other gauges not working also.
vacuum lines (have been cut)
currently am raising the lights and lowering them by hand.
horn is removed/disco'd from the steering wheel.
fuel filter in wrong location. (suggestions welcome after seeing the photos)
power steering leak(front driverside)
auto-windows are gummed up and slow to rollup if not with help.
no ac

let me know what else you see here that may help me get this project complete, as in 'a somewhat reliable/drivable non-show vehicle'.

thanks
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Old Jul 7, 2014 | 08:59 AM
  #2  
Rotonda's Avatar
Rotonda
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Joined: Sep 2006
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From: Rotonda FL
Default

overview of all my issues:
speedometer/odometer not working.
some other gauges not working also.
vacuum lines (have been cut)
currently am raising the lights and lowering them by hand.
horn is removed/disco'd from the steering wheel.
fuel filter in wrong location. (suggestions welcome after seeing the photos)
power steering leak(front driverside)
auto-windows are gummed up and slow to rollup if not with help.
no ac


speedometer/odometer not working. - your photos don't show the area, but 77's were typically equipped with cruise control. If yours is, the transducer is probably shot. Transducer is located on left side engine compartment and identified by two cables screwed into it. I solved this problem by replacing the two stock cables (trans to transducer and transducer to speedo) with a single cable from a non cruise car.

vacuum lines (have been cut)
currently am raising the lights and lowering them by hand.

Replace all vacuum lines as a start, then you can begin to diagnose your headlight problems. If there are many, you may want to consider converting them to electric using Ford Probe or Miata motors. Do an advanced search for more info.

fuel filter in wrong location. (suggestions welcome after seeing the photos)
FIRST PRIORITY!! Extremely dangerous! Inspect your fuel supply line. It is a 3/8 diameter METAL line that runs along the right frame rail (on top of the kick-up by the right rear wheel and along the inside of the rail under the passenger compartment). If it is rubber or has rubber splices, it needs to be replaced with steel OR, at a minimum, braided stainless. The position of the current fuel filter makes it very vulnerable to damage by road debris and subjects it to vibration and heat (from brakes) that can deteriorate the rubber hoses. Any breach will drain all of the fuel from the tank, and the plastic in the Corvette will only feed any fire.

power steering leak(front driverside) - You have this in common with virtually every C3 owner. I finally resolved the issue by installing a modern Borgeson/Jeep 600 steering box. The original GM design is a high maintenance design with many failure (leak) points.

auto-windows are gummed up and slow to rollup if not with help. - Pull the glass , clean and lubricate the tracks and install new rollers.

no ac - A big topic with C3 owners (do a search). Early 77's came with GM's VIR system. Late 77's came with the current, more modern orifice tube system. Mine was an early 77 and I elected to install a Vintage Air system (see my previous write-up on adapting Vintage Air to a 77). If you have a late 77, you can restore it to function with cleaning and new parts - again, do a search for all of the necessary for this restoration.
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Old Jul 7, 2014 | 11:36 AM
  #3  
scottyp99's Avatar
scottyp99
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Joined: Mar 2008
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From: Oxford MA-----You just lost the game!!!!
Default

I've already lectured you about the wonky fuel line in another thread, so I'll just move right along and suggest that you check out this link in regard to your headlight problems:

http://forums.corvetteforum.com/c3-t...tem-works.html

Once you understand how the system is supposed to work, you'll see that it is actually fairly simple. No need to spend exorbitant amounts of money on electric actuation and such. Just fix the existing system, that's all.

Scott
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