The car has a "unibody".... the entire metal structure is stressed to some extent. Screwing the cover plate securely will replace any stress absorbtion capabilities of the area you cut away. May be very minor, but the chassis should not have it's strength diminished. Additionally, in the event of a rear or rear quarter panel collision or a roll over, the impact and twisting of the chassis will probably pop the RTV loose, and now you have a gaping hole right above (or below if the car is upside down) the fuel tank...... potential for fuel to enter the passenger compartment.

I would strongly advise using a sealant AND using numerous screws or pop rivets to insure the panel stays in place.

I would also recommend that the cut out hole does not have any "square" corners..... they will serve as stress risers and promote cracking of the sheet metal. Radius the corners.

Super conservative... yes, as a licensed professional engineer, it would be irresponsible of me to state otherwise.

 

Makes sense to me... it'll only take a few more minutes to do the screws. I hadn't thought of the potential problems in a crash. We're going to put big radii on the corners, and I bought a set of air shears to cut it nice and straight too. The grinder and sparks right above the gas tank that I saw in so many videos made me cringe!

 

The links posted at the beginning of this thread seem to no longer apply. The 1st and 3rd links gave me a "page not found error" and the middle link went to the guy's car page on Car Domain with no information about the trap door that I could see.

 

Did you try the links in posts 102, 105, plus Kevin's photo in 111? Also see 84. Work backwards from the newer posts.

 

Yep, saw those. Ended up reading the whole thread.

 

KYWes, I did this job two years ago and chose to make a small cut in the shock support brace that stops you from making a sufficiently long door for the convertible.
I have a few photos but can't add them to this post. The cut I made is only to the horizontal flange part (1/2 inch max) of the support not the structural angle.

Even with this it was VERY tight fit to remove the pump and refit the pump, hoses and electrical connector. It did work but if you can lower the tank like referred to above it should work better.

I just checked my car and 25,000 miles later I do not have any cracking visible to the cuts on the support bar and the trap door I caulked then screwed in place with short self drillers is still nice and tight.

Good luck!

 

If you could upload the pictures using this procedure, it would be helpful:

https://www.camaroz28.com/forums/sit...28-com-699204/

 

Using the instructions kindly provided by Injuneer I (finally) sorted how to post pictures of the trap door in my convertible. I have an album located in my profile. I'll try to post some here too......





CamaroZ28.Com Message Board - squarehead's Album: Fuel pump trap door pics for 95 convertible - Picture



I hope this worked!

 

Squarehead, thanks for posting your pictures.

I went ahead and cut me a trapdoor. I elected to not cut into the shock brace as I did have the tank lowered from trying to remove it. I was able to reach through the hole and install the new pump.

Now I just have to find time to reinstall everything.

 

Hoping someone is currently active that can help.

I've got the trap door cut and the pump in.

I've printed out the diagrams from Shoebox's site regarding the evap lines.

I'm having trouble figuring out where the lines connect to.

Specifically the large tube with the purge valve that runs from the canister to where?

From my tank I've presently got the following lines going to:

Looking at the tank from inside the car with the lines facing the front of the car.

The far left line going to a short rubber hose and then to the evap canister; but to which port I'm not sure.

The second line from the left goes to a quick connect and then I've got it going to the fuel filter.

The third line from the left goes to a short piece of rubber hose and then to the tank vent.

The fourth line from the left goes to a quick connect and then to a line leading up to the engine compartment.

Sure hope you can help me out of my mess. I've looked at all the pictures in this thread but they only show the pump, not where they go to. I also can't trace Shoeboxes diagram's well enough to figure things out.

 

The factory line routing diagram sort of sucks.

Shoebox's diagram shows the canister, with the three connections labeled:

http://shbox.com/1/evap_system.jpg

1 comes from the tank

2 admits fresh air

3 goes to the purge solenoid on the engine bracket.

The fuel supply and return lines (quick connect) are different sizes (3/8" supply; 5/16" return).... should only fit correctly on the correct connections.

 

Fred, can you double check the accuracy of this diagram markup?

 

Looks 100% correct to me. About 1,000% clearer with the colors.

What is the brown line? As I recall, there are only two hoses to the canister? I can't check on my 94, because the EVAP has been deleted (track car) and the fuel lines are converted to braided SS.

I have a spare sending unit. I think I will supplement what you have done by taking a picture of the top and labeling the four pipes.

 

You're right the colors help tremendously. I was also wondering about the brown colored line. Also doesn't the sending unit in GaryDoug's post just show three lines coming off the fuel pump / sender? Everything I've seen it has four lines. Am I just missing seeing one in the diagram?

 

The 4th line is for the pressure/vacuum vent valve, and he has added a separate detail in the lower right corner.