suspension pan maintainence

[tahoe_snow]

I've been working on the front of my car this spring, and one area I'm taking a close look at is the suspension pan.

I've inspected it pretty closely, but based on a lot of threads on this board, I am concerned about the long term health of this panel.

I am considering removing gas tank support to closer inspect, have any problem areas patched, and then por-15. From the bottom it doesn't look like a problem, but I understand this area fails from the inside out.

So my question is, is it worth drilling out the gas tank support just to do preventative maintenance on this part of the car?

TIA

[Rot 911]

Be helpful to know what year your 911 is, but in any event, if the pan is solid underneath I would just leave things as they are.

[Rich Lambert]

Whoa, that's a little exteme. If you're concerned about rust, attack the areas around the suspension attach points with an ice pick. If it doesn't go through, I'd leave it be.

[Zeke]

It's worth it to drill an inspection hole on each side. Get the plug your are going to use to fill the hole first. After you can see inside in the critical areas, treat accordingly. When it's ready you can get POR 15 in there in a variety of ways. I pour it in and blow it around with a long, curved air nozzle extension. I also load a neoprene hose with whatever preservative I'm using, insert to a target area and attach some air to disperse. I've gotten way up in the nooks and crannies on 3 cars now.

[bob tilton]

Originally Posted by milt

It's worth it to drill an inspection hole on each side. Get the plug your are going to use to fill the hole first. After you can see inside in the critical areas, treat accordingly. When it's ready you can get POR 15 in there in a variety of ways. I pour it in and blow it around with a long, curved air nozzle extension. I also load a neoprene hose with whatever preservative I'm using, insert to a target area and attach some air to disperse. I've gotten way up in the nooks and crannies on 3 cars now.

Clever.

[tahoe_snow]

Milt,

That sounds like good advice. The car is a 74. It is pretty clean, but the thing that makes paranoid about the suspension pan is that it seems there nothing to do until it is way too late. Plus there are some signs of battery leakage in the past.

I've gone through the bottom of it with pick, and it seems solid. Only thing that bothers me is that I can hear some loose metal banging around.

Where would you recommend drilling the inspection holes, and what size?

Thanks again...

[Zeke]

As I said, depending on your local supply situation, look for some suitable plastic plugs. Maybe around 1" to 1 1/4". I made up an extension for my shop vac that is a series of smaller hoses. I can go down to about 3/8ths ID and suck debris out of the smallest places. I'll use compressed air at the same time to move all the loose stuff around eventually getting vacuumed up.

Next step is phosphoric acid. Put it in with the same hose tricks. Watch for spills and spray. Watch your skin and eyes! You could drill some small drain holes at the bottom, but most of the cars had factory drain holes. It's just the usual rust abatement process.

[RWebb]

pic of where to drill holes?

[Zeke]

I would drill them above the a-arm mounting points. Since you are drilling in the tank support, there aren't too many choices. The mounting points are low points as well, so that seems to be where the rust is. Or what I called "critical areas."

[tahoe_snow]

This seems like a good plan. I'll see if I can source some plugs. I'll let you know how it goes.