Birty Dastards Jeep Club

Tech Forum => Workshop => Topic started by: Brynjaminjones on July 28, 2013, 10:42:43 AM

Title: "Rustproofing" the underside of an XJ
Post by: Brynjaminjones on July 28, 2013, 10:42:43 AM
I've been thinking about this for a while, but thought it's time to actually do something.

The underside of my XJ is currently in fairly good shape (I think!) with no real rust. However, the paint/coating on the "frame" rails is starting to flake away in a couple of places as it didn't much like the pressure washer. :banghead:

I'd like to treat the whole underside somehow, to minimize the potential for rust to start, and to cover up the gaps where the paint (or whatever it is) has flaked.
I'm a bit clueless about this, so what options are out there, and what's the best to use??
Title: Re: "Rustproofing" the underside of an XJ
Post by: eastryjeep on July 28, 2013, 11:12:30 AM
Waxoil or similar as you can see when it gets damaged or if some nastiness starts on the metalwork beneath the protection. Its for this reason alone I now hate the thick black gloop you can buy because its going to be too late to do anything if its all masked up covering the rot!
Mind what you put above the exhaust run as that will need to cope with heat and warm salty water in winter, I use aluminium or zinc based paint there after a good going over with the Kurust.
Title: Re: "Rustproofing" the underside of an XJ
Post by: Bubba on July 28, 2013, 11:37:34 AM
I strongly like spraying mine with old engine oil its free works well too



Yes I know its v old school backwoods but  heyhoo
Title: Re: "Rustproofing" the underside of an XJ
Post by: Hillbilly on July 28, 2013, 12:21:07 PM
 :iagree: Downside is it can drip for a while so best not park where a few oil spots might cause a problem.
Title: Re: "Rustproofing" the underside of an XJ
Post by: UKJeeper on July 28, 2013, 02:37:59 PM
I strongly like spraying mine with old engine oil its free works well too





Still thinking of getting a Landy then? (it sprays itself...)
Title: Re: "Rustproofing" the underside of an XJ
Post by: XJ Fan on July 28, 2013, 06:35:24 PM
:iagree: Downside is it can drip for a while so best not park where a few oil spots might cause a problem.

He has an XJ - I'm sure no one will be worried about a few more oil spots......
Title: Re: "Rustproofing" the underside of an XJ
Post by: Brynjaminjones on July 28, 2013, 07:22:24 PM
 :imwitstupid: My XJ does like to mark her territory (intermittently)...
Title: Re: "Rustproofing" the underside of an XJ
Post by: Dave69 on August 23, 2013, 08:31:20 PM
Clean each bit then paint with chassis enamel or smoothrite
Title: Re: "Rustproofing" the underside of an XJ
Post by: bgbazz on August 23, 2013, 09:12:39 PM
If you keep the inside of all cavities free of crap..Gaz recently bought himself a solution to help with this, so just ask him about that. The flaky bits on the outside need to be buffed off with a drill wheel or similar and treated with a dose of Hammerlite or whatever the other guys are using.
It's the unseen collection of moisture and crap which will do the damage!!
Title: Re: "Rustproofing" the underside of an XJ
Post by: JamesH on August 23, 2013, 09:21:18 PM
I've been going through mine for all the reinforcements I've been doing and the rust spots are hard to find. I cleaned mine done, removing underseal, then paint, then galvanised layer and all looked fine. It was only when I was welding that a few spots were obviously rusting because it just popped and wouldn't weld.

From this I'd say the previous advice about cleaning the inside regularly was best. Obviously treat any rust you can see but otherwise I'd say just slap some underseal or black hammerite on where the factory underseal has come off.
Title: Re: "Rustproofing" the underside of an XJ
Post by: tag on August 24, 2013, 01:14:14 PM
I use hammerite  underseal,    good stuff !  not the usual horrible  underseal,  its mixed with waxoil  easy to brush on hardly any drips  it has a waxy  buttery texture, never sets or drys been using it  a few years...... :icon_winkle:

Title: Re: "Rustproofing" the underside of an XJ
Post by: Ditchd on August 24, 2013, 05:30:39 PM
On several vehicles for a long time I've been using the Hammerstein under seal as above, it's excellent. Then covering with several thinned layers of black waxoyl via a cheap electric sprayer.

Never had any problems at all with underside corrosion apart from when enthusiastic use of the under seal blocked a drain hole on the SEAT sill .....lesson to be learnt I guess
Title: Re: "Rustproofing" the underside of an XJ
Post by: Mike2909 on August 27, 2013, 10:42:43 AM
I have used this product for quite a few years with astonishing results  Fertan . http://fertan.co.uk/fertan-vp-index.htm

I use it as an undercoat on to bare metal, rusted metal, and then use the waxoyl products on top. Having owned Alfas  :010: for years I became quite an expert in rust  :017:.

I learned about this product from a friend who buys and sells boats and he showed me the results he had with it.
Title: Re: "Rustproofing" the underside of an XJ
Post by: Fizz on August 30, 2013, 07:55:04 AM
If you got an airline I bought a schutz gun and didvthe underside of mine with tetraschutz
Title: Re: "Rustproofing" the underside of an XJ
Post by: gazjeep on August 30, 2013, 07:05:57 PM
Got one of these to feed down the inside of the chasis rails on the TJ. works wonders flushing out all of the build up of off roading crap

http://www.amazon.co.uk/Karcher-Drain-Cleaning-Hose-attachment/dp/B005NZAHH8

Then bought a garden sparyer like this
http://www.amazon.co.uk/Litre-Action-Knapsack-Pressure-Sprayer/dp/B00CSM54JK/ref=sr_1_2?s=electronics&ie=UTF8&qid=1377885878&sr=1-2&keywords=garden+sprayer

Spayed de-watering oil (got plenty at work) inside the chasis, will repeat the excercise after cheapfest
Title: Re: "Rustproofing" the underside of an XJ
Post by: bgbazz on August 31, 2013, 07:55:46 AM
Got one of these to feed down the inside of the chasis rails on the TJ. works wonders flushing out all of the build up of off roading crap

http://www.amazon.co.uk/Karcher-Drain-Cleaning-Hose-attachment/dp/B005NZAHH8

Then bought a garden sparyer like this
http://www.amazon.co.uk/Litre-Action-Knapsack-Pressure-Sprayer/dp/B00CSM54JK/ref=sr_1_2?s=electronics&ie=UTF8&qid=1377885878&sr=1-2&keywords=garden+sprayer


The drain cleaner thingy is the bit of kit I mentioned in an earlier answer Bryn

Spayed de-watering oil (got plenty at work) inside the chasis, will repeat the excercise after cheapfest