To strip or not to strip, that is the question?

[drcoastline]

While stripping the tar off the the floor I came across some rust around my pedal cluster. I scrapped around and wire brushed a bit. It feels ok. I dont want to remove the cluster just yet so I went under the car with my grinder and a cupped brush. Wired the under body coating off the area. Looks good no issues from the bottom. So I don't think I have a major rust issue in this area. For good measure I squirted on a liberal amount of metal prep.



I moved over to the passneger side and found a small rust through near the tunnel. So I went under the car and found this. I am going to cut back to good metal and weld in a patch.



While under there I removed the skid plate and looked around. Checked all the suspension points. They look good. In time I will remove the parts to inspect more thoroughly repalce busnings, clean things up a bit and so on.

I noticed under the battery tray the under-coating was loose and bubbling so I used my scrapper to see what was happening. Some surface rust but the area feels solid. I went back up top to check things out. A bit of rust around the edge of the gas tank support.



Thinking this could be a problem I removed the tank and found nothing.



I am going to strip the battery try area, metal prep the bare metal. POR15 the tray area . Lay in a piece of commercial grade rubber roofing for the battery to sit on, paint and call it day.

Do I have any reason to do anything on the tank support other then clean it? reseal the edge of the tank an drop it back in? I will give the tank a once over. clean it, paint it or hit it with a light coat of SKS before returning it to it's home.

Opinions please. Any "while you are there" comments are also welcome.

Thanks.

DR

[PropellerHead]

You're doing the right things. Catching this type of damage before it causes more serious problems. For the surface rust, get a wire wheel and perhaps even a grinder to get all the rust off. Then prep, seal and paint. You can use POR15 products or a good epoxy sealer and it will be ready for paint.
You would be much wiser to remove the pedal cluster and ensure you get all the surface rust dealt with or it will simply ruin your work and eat the metal under what you've so wisely investigated, etc.
The through hole will require cutting, patching, etc. as you've already figured but is a realtively easy fix at this stage it appears.

[boba]

Originally Posted by PropellerHead

You're doing the right things.

You would be much wiser to remove the pedal cluster and ensure you get all the surface rust dealt with or it will simply ruin your work and eat the metal under what you've so wisely investigated, etc.

+1 One thing to keep in mind is that you may have had brake fluid in that area in the past which would make it worth the time to remove, clean and repair. You have done such a thorough job, why skimp now.

[ghost1001]

looks like my pedal area prior to stripping and rebuilding....I had zero rust issues, just surface. I think people get into the car with wet shoes and water drips there and sits....hence rust.

I agree that at some point you should remove the cluster to get it all....

before

after

[500_19B]

You will want to assess the possible rust damage that may lurk in the void between the fuel tank support and the suspension pan. The fuel tank support is the metal pressing just ahead of the fuel tank, and incorporates the battery tray. It is VERY common for battery acid damage to exist in that void as people often only clean what they see when a battery leaks. The bottom of the suspension pan in this area is where the lower control arms mount, so it can potentially be a structural issue. Ultimately it can end up with the lower control arm mounts tearing off.

Of course, I hope you dodge that bullet, but you really have to check it carefully. I had VERY little visible rust in my battery area, but that void was another story. Look at the pics on the first page of my thread about this and you will see the areas I am describing.

Good luck!

Battery-area surprise! - Rennlist Discussion Forums

[la2mtl]

Is the removal process and refitting difficult? I was considering the job on my own, but the mechanism scares me... Is there a thread showing the procedure? The 'after' picture just sells it for me!

Steve

[NoLift911]

Do it now while it is cheap - or do it later when it's not....and worse. You are going in the right direction. I would wire brush all of that down to shiny so you know what you are dealing with.

My 02, I would pull that peddle cluster and wire brush all that off - also see what you are dealing with under the cluster and around it - intead of just a visual use something super sharp to poke around - ice pic, nail set etc - to the eye it may seem fine but if you start poking, it may reveal other stuff.

Again - just what I would do since you are "in there" and "in it"....

[shnewberry]

Wayne's book, 101 Projects for your Porsche has an excellent how-to for rebuilding the pedal cluster. You will want to do it after reading the chapter. It is project #40 in the book.

[drcoastline]

Prophead, ghost, boba, 500, P-Dawg

I will be doing the pedal removal in short order. I just don't want to remove it until I get a few other things back together. I have more checking on the interior floor and some rust repair welding on the back seat pans and finish the battery tray before I take more apart. When I take the pedal cluster out I will rebuild the cluster and refinish the floor under the pedal.

Am I missing anything else?

Do you think it is ok to leave the gas tank pan alone? Just clean it and replace the tank?

la2mtkll- I am assuming you are asking about the pedal cluster rebuild? I cant help with your question yet but when I do the rebuild I will post.

Thanks again.

DR

[drcoastline]

Shnewberry- Sorry posted before I saw your post. I agree. I will be rebuilding the cluster at the same time I clean the floor pan in the cluster area.

[moneymanager]

Pedal clusters are easy and cheap. Would not surprise me to find some serious rust underneath. Doing it now is the right thing to do.

[ghost1001]

The pedal cluster rebuild is a good weekend project, the hardest part is getting the roll pin that holds the whole deal together out (old) and in (new).

I suggest getting a perfectly sized center punch and driving it out with a hammer....mine came out with no issues. Back in is harder, 101 projects is good, but offers no advice in this area. I used a bench vise to "press" it back in, a hammer and punch will not get the new one back in, to use the vise everything must be perfectly square or it will not work...and then it takes serious force to push it in. I think a machine shop that has a press could make short work of this, but i like a challenge.

Further, upon review of your pedal cluster I see that your pin (circled below) is sticking way out one side of the main tube.....mine is not like that.

I think you should check that the pin is proud of the tube on the other side as well, if not this should be addressed as the pin could fail.

Do others agree?

Kevin

[500_19B]

Good catch! That pin definitely looks further out than I would expect, but it could just be that it is a longer pin than I have.

If you go the route of rebuilding with the popular bronze bushing kit, I would highly recommend not using the pin that comes with the kit (a conventional split pin) but instead buy the OE pin, which is a coil type and much stronger.

Porsche part number for the pin is 900 309 002 00, PET description is "pin 6 x 28"

This part number seems to be the same for early and late cars.

[drcoastline]

500-19B

Is the pin a one use only pin or can it be reused assuming I get it out without damage?

Does everyone agree I don't need to do any further work on the tank support?

Thanks again for all the input.

DR

[boba]

I cannot tell for sure from the photos, but did your car have AC and a front condenser? One of the photos looks like it might have.

Since you have everything out it might be worth it to see if you can find a bore-scope and have a look at the space under the tank support. The factory did nothing in the way of rust protection in any of the inter-panel space. So bare metal has been rusting since the day it was welded together. Now would be a good time to have a look.

[drcoastline]

Bobba-

yes it did have A/C at one time. That was the first thing I removed.

Where exactly should I be looking for this bare metal under the tank support?

[boba]

This is the top view of the front suspension pan.



The red section is the tank support.



On the original build the panels were welded together and the bottom surface of the tank support and the top surface of the suspension pan formed a void which remained bare unprotected metal. While the top of the tank support and the bottom of the suspension pan got primer, paint and undercoat. There are many of these voids in these cars where multiple panels form structural members with no rust/corrosion protection within the void. The cars literally can rust from the inside/out. The rockers are another area we see often.

With the addition of battery acid, plugged drain holes, and the instillation if the front condenser the front suspension pan is a hot spot.

The rust will be on the upper and lower surface of the void formed by these two panels.

Hope this is clear and helps.

[drcoastline]

Bobba,

I poked around per your advice. I didn't see any signs of rust. All seems intact as best as I can tell.

The photo attached is not from my car but one I found in the paint and body work forum. I think this shows the two pieces mated together that you speak of? Am I correct? If so the only gap in these two parts I could locate is the section I have circled.



After stripping the battery tray and surrounding areas the rust all appears to be surface rust. The rust I noticed from underneath that prompted me to strip the battery tray area turns out to be what looked like two screw holes that must have allowed some moisture in to loosen the coating. They have now been welded shut.

[boba]

I found this photo which may help to show the void I have been referring to. It also shows two holes which I hope are not the ones you welded up as they are drain holes and would be fitted with rubber inserts which keep water out but let it drain.

As you can see in the photo the tank support is just laying across the space where the tank would fit. You can also see some corrosion on the top surface of the suspension pan. This is within the void created by the two panels, tank support and suspension pan.

[boba]

OK, I found Curt's bore-scope of a 911 suspension pan.

YouTube - 911 Pan Inspection with Borescope!