Remove old undercoat or not?

[TKR514]

I'm doing my first Z restoration. I removed the front and rear suspension and fuel tank. There is no rust underneith the car except for some minor surface specks close to the rear bumber mount.

Can I just wash it and call it good OR do I need to strip the entire undercoating /paint, then repaint and reundercoat?

[St.stephen]

Well in all honesty I would say yes you need to remove the old undercoating. See, rust starts under the undercoating, so something that looks solid, when you hit it with a scraper will reveal another story. I found several places in the inner fender well and even in the firewall that had rust you could not see.

if you have the suspension off of the car already you are already halfway there. The car is probably never going to be apart more than it is now so why not address EVERYTHING now, rather than after the fact.

do a search on the site about this process. Escanlon, 2manyZ's, myself and a host of others have posted tips about the removal of the undercoating, rust prevention, and restoration.

Doing it RIGHT at this point, will surely help provide a long lasting, solid project.

[EScanlon]

Unless you plan to disassemble the car to this extent several times during the time period you own it, you might as well do it as thoroughly as you can afford, have the time available and are willing to do it. It will pay itself off over the years.

Yes you may find some unpleasant surprises.

I found that the "mild surface rust" on the floor pans was actually the beginnings of total rust through and in a year or so I would have had Flintstone brakes. My front fenders had a couple of minor "rust bubbles" under the paint, that turned out to be massive gobbs of packed rotting leaves / needles that were just holding nice moisture up against unprotected metal. Plus other incredibly joyful (note the sarcasm) discoveries.

Would I have been better off NOT doing it? I don't think so. Yes, it was a bear of a job having to do all that work, and the expense was not something I relished, but thankfully, I feel that it will make it that much easier to work on the car in years to come.

So ask yourself this, do you honestly TRUST that there are no problems underneath the undercoating? If so, leave it be and address it if and when problems arise.

Do a simple test, get a pressure washer and blast away the grime, oil, and other stuff that will come off. If you're lucky, you'll blast off the bulk of the undercoating and discover that there aren't any problem areas. That is what you want. Then do a proper undercoat following the directions and you will have satisfied yourself that there are no problems.

If on the other hand, you find problems, you will be extremely grateful to have caught them before they become killer items.

2¢

[PetesPonies]

I'm going to differ from the first two suggestions...but on a technicality. If the undercoated in truely uncracked, not loose etc, then it may not have to come off. That is the key though, is it really in good shape. The only way to tell is by scraping. But when you run across some that doesn't want to come off, well them I usually leave it. I do restoration work. It depends on your goal, but if a daily driver is the goal, then I find it acceptable. However, I reiterate, if the undercoating is really in good shape. Not loose, slit, cracked etc.

[EScanlon]

Pete:

I agree with you. However, of the 4 Z's I've had personal experience with, all of them had either had the undercoating "retouched" or seriously scraped off due to high centering on obstacles, poor jack placement, or whatever.

At that point, I go back to my statement of "TRUSTING" that it's ok. I like to "Trust....but verify.".

2¢

[Nigel Mulvey]

Do it once do it right!

(May be George Bush Snr should have followed that axiom).

[Bambikiller240]

Originally posted by Nigel Mulvey

Do it once do it right!

(May be George Bush Snr should have followed that axiom).

Yeah, maybe then we wouldn't have his PINHEAD son trying to force the US into a battle that the rest of the world doesn't seem prepared to support the US in fighting.

We should have taken Saddam out the first time.

[TKR514]

Hey, I just want to keep my car running...

I (Like GW Bush) don't care what France thinks :-)

[ZmeFly]

jsut do it :cross-eye

[Ivan]

yes might as well, heat gun and a scraper works good