'72 frame/underbody pics, what is incorrect/missing?

[Douglas M.]

I know of the following issues:

All ground straps seem to be missing.

Exhaust hanger mount at rear of trans has a broken ear.

A clip is broken that holds a trans cooler line to the front crossmember.

Trans lines seems to be too low next to oil pan, I think a bracket is missing?

A wire retaining clip that holds wires to solenoid seems to be missing.

On the pic showing the lower radiator support, is the ~1.25" wide black reinforcing strap between the air dam and body supposed to be there? or it that an add on?

On the one pic, showing the top of the fuel tank, what appears to be a vent hose (maybe 2-3' of hose) coming out, is all coiled up on top of the tank, it that normal?

See the broken cable connector hanging down off the trans linkage? I was told some sort of cable connects to the steering column? What does that do


Please list anything you see that is wrong/incorrect. I know about the shocks.

[Jim T.]

Re: '72 frame/underbody pics, what is incorrect/missing?

Douglas I have a 68 and 70 so my answers are based on my Corvettes.

The L-shaped steel bracket at the front bolted to the crossmember is original and there should be two of these.

Ground straps, my 70 only does not have ground straps connected to the muffler clamps like my 68. The important gound on my 70 goes from my engine block on the passenger side to the frame. I believe I can see yours. There is also a ground that connects to one of the starter retaining bolts.

The automatic transmission lines on my 70 has a bracket hanging from a oil pan bolt supporting the tranmission lines and is rubber lined steel bracket.

Another bracket attaches to the frame above the lower control arm and retains both transmission lines.

Also have the bracket on the starter solenoid to retain/support wiring.

Did not see the picture with hose on top of the tank. My 70 has two fuel lines. One is a supply fuel line to the fuel pump from the connection on the bottom of the fuel tank. The other fuel line is a reutrn fuel line that connects to the top of the tank from the fuel fuel pump..

A drain hose from the rubber surround of the fuel tank neck to the rear bumper, fits on the inside of the vertical portion of the passenger bumper. Don't remember how many ties are used to retain it.

Enjoy your 1972.

[Paul O.]

Re: '72 frame/underbody pics, what is incorrect/missing?

Doug

1. On a 72 only 1 ground strap at the Left #1 body mount.
2. If you are speaking of the 8th photo that is normal.
3. The check valve was added in 1971 it is the fuel vapor connection tank to the charcoal canister the upper hose looks to be a replacement along with the clamp. The valve has a float ball inside that prevents raw fuel from entering the charcoal canister just vapors.
4. That cable is for the steering lock when the car is in the parked position and the key in off.
5. Rear caliper brake lines are hand made not typical.
6. Rt exhaust tip is a service GM replacement.
7. Rear strut rods appear to be later service replacements large head.
8. The exhaust pipe hanger on an A/T is configured different then a standard trans.
9. The bolts holding the front air dam are installed reversed and should have blacked finish nut on the front side and bolt head facing to the rear.

That is what comes to eye just quickly.

Paul 18046

[Douglas M.]

Re: '72 frame/underbody pics, what is incorrect/missing?

Thank you.

This is a pic of the top of the tank with the vent hose. The pic doesn't show the vent hose all coiled up, just its connection at the tank/black box. I can't actually see up there, this is a spy cam shot. OK, so one of the hoses shouldn't be coiled up,and should drain on a rear vertical bumper piece.

Where does the other hose on the black attachment box go to?

Thanks,
Doug

[Douglas M.]

Re: '72 frame/underbody pics, what is incorrect/missing?

Doug


3. The check valve was added in 1971 it is the fuel vapor connection tank to the charcoal canister the upper hose looks to be a replacement along with the clamp. The valve has a float ball inside that prevents raw fuel from entering the charcoal canister just vapors.
4. That cable is for the steering lock when the car is in the parked position and the key in off.

Thank you very much!

Re #3, the black box is separator, one line is the overflow drain line and the other goes to the charcoal can. Got it!

Re #4, that is why I can put the car in gear when the ignition is turned off, an entire cable assembly is missing to the column.

All of my wrenching experience is on C1/C2, the newer cars with emission control and anti theft stuff is new to me. Gotta figure out why the alarm doesn't work sometime, also.

Amazing what gets done to a car in 40 years...

Doug

[Paul O.]

Re: '72 frame/underbody pics, what is incorrect/missing?

Doug on the drivers side of the frame you will have 2 metal lines 1 is the brake line the other goes from the charcoal canister it is below the vacuum tank to the fuel tank then points up and the hose is connected there.

Doug what Jim is referring to is the gas tank fill neck overflow hose that is at the rear valance by the bumper support rod. On the separator 1 line comes from the tank and the other goes to the line to the charcoal canister.

Paul 18046

[Douglas M.]

Re: '72 frame/underbody pics, what is incorrect/missing?

Doug what Jim is referring to is the gas tank fill neck overflow hose that is at the rear valance by the bumper support rod. On the separator 1 line comes from the tank and the other goes to the line to the charcoal canister.

Paul 18046

Got it.

Thanks for clearing that up. Wasn't aware of three lines attached to the fuel pump on the '1970's cars (in, out and vapor recovery).

The hose all coiled on top on the tank still needs to route down to the rear bumper.

Doug

[Edward J.]

Re: '72 frame/underbody pics, what is incorrect/missing?

Doug, The lower shock nuts appear to be incorrect, and it looks like a replacement idler arm as the factory ones did not have a grease fitting, and tie rods appear to be replacements.
If you want to take a look at my signature I have a photo bucket with some pic.s of my 72 under carraiage you can see what the correct nut looks like for the lower shocks.

In 72 I Think that the drain hose that the guys are talking about has one or two ties that attach to the vertical support bracket on the pass side.

[Kevin G.]

Re: '72 frame/underbody pics, what is incorrect/missing?

Doug,

One more item, not sure if the fuel tank has been removed and reinstalled but I don't see the anti squeak "felt" between the tank and rear metal frame rail? I believe it should be visible about 3/8" along the length. I just happen to inspect this very thing today for a friend on both my 71 and 72!

[Paul O.]

Re: '72 frame/underbody pics, what is incorrect/missing?

Doug on a 1972 base motor small block 2 metal lines for fuel passenger side 1 to the pump the other is a fuel return line to the tank. Drivers side 1 fuel vapor metal line tank to charcoal canister and fuel vapor separator check valve. Then at the fill neck is a scupper around the fuel fill neck at the back of the scupper is a drain opening and the a rubber hose is connected that runs from the scupper to the area around the rear exhaust valance this is to drain fuel over flow when filling and or water from rain or washing. The hose is then some times routed to the RT rear bumper support rod and drains through the down ward point part of the bumper or as we have seen just hanging and pointing straight down from the rod as yours maybe.


Paul 18046

[Michael W.]

Re: '72 frame/underbody pics, what is incorrect/missing?

Got it.

Thanks for clearing that up. Wasn't aware of three lines attached to the fuel pump on the '1970's cars (in, out and vapor recovery).


Doug

Doug, the third line on the pump is actually a return/bypass for fuel recirculation purposes in order to reduce or eliminate vapour lock in the fuel pump itself. The constant flow of fuel through the pump keeps the local temperature lower than would a simple in and out two port pump.

Should vapours accumulate in the pump, such as during during the heat soak period after shutdown, they would be carried back to the tank with the returning fuel instead of to the carburetor where stalling or no start may occur.

The vapour themselves are absorbed and later eliminated with the charcoal canister which is a independent system.

[Thomas H.]

Re: '72 frame/underbody pics, what is incorrect/missing?

Looks like the foam seal is missing in the first picture between the shroud and radiator.

Tom

[William M.]

Re: '72 frame/underbody pics, what is incorrect/missing?


Drain hose should be fastened to the bumper support rod with 2 black cable ties


Missing the 2 battery vent hoses