Underseal us every where & rust - what to do??

[pockers]

In the process of trying to repaint my jeep and sort any rust, I have noticed the entire underneath - body & chassis has been undersealed some time ago.

This has split/cracked in places creating a water trap and causing rust with the underseal just flaking off.

 

At the moment the underseal seems to be doing more harm than good.

 

 

Should the under body even be undersealed?

Am I best removing the underseal, sorting any rust, prime , paint and then treat with waxoyl or

Is it best to remove the old then re underseal ?

 

Any advice greatly appreciated

Edited May 25, 2011 by pockers
Spelling mistakes

[Rover8FFR]

The waxoil product underseal is excellent as it stays flexible so won't crack. Just never clean with a HOT pressure washer as it tends to slowly dissolve and wash away. Thats what I was told.

 

If the underseal on your jeep is anything like the liquid tar painted on my old lightweight then removing it all would be a 'Bar Steward'!

[JOURNEYMAN]

Hi pockers,

when i re-built my lightweight land rover, it had a layer of solid underseal on the chassis and

body panels which had started to flake off. I found the easiest way to remove it was to take all

the loose bits off first and after softening the remainder with a hot air gun, i found it came off

easily. It,s a bit smelly and time consuming , but worth the effort when you end up with a clean

panel. All i did then was degrease the panels / chassis , prime them and spray a couple of top coats. I used black waxoyl in/on the chassis but left the panels painted. Any rust was obviously

treated before priming.

Hope this helps,

steve.

[Nick Johns]

 

 

Should the under body even be undersealed?

Am I best removing the underseal, sorting any rust, prime , paint and then treat with waxoyl or

Is it best to remove the old then re underseal ?

 

Any advice greatly appreciated

 

No Jeeps were ever undersealed, body underside should be painted as per the rest of the body, don't re underseal !!

Edited May 26, 2011 by Nick Johns

[pockers]

Many thanks for the replies

 

its a show vehicle & i dry store it over the winter so once the rust is sorted it shiould stay that way for a while

 

looks like i got some work to do but will be worth it

 

i'm going to strip off the underseal, sort the rust, prime & paint

[Nigelr32]

Just as a little extra advice...

 

If the underseal is Waxoyl based, Turpentine will remove it, if bitumen based, an old T-shirt soaked petrol will do a great job of the final clean up for you.

 

Nige

[Tony B]

I've done quite a few with ordinary black roof paint. Cheaper than all the specioal Chassis paint, and works just as well.

[trustmeimamechanic]

No Jeeps were never undersealed, should be painted as per the rest of the body, don't re underseal!!

 

Every ex Dutch M38 A1 that I have seen has layers of underseal sprayed on everything .

I spray under my Jeep and also my Landcruiser with a mix of new engine oil and diesel at the start of every winter - on the Jeep you can see where it seeps right through all the spot welded seems that are such a rust and water trap.

[Big ray]

Every ex Dutch M38 A1 that I have seen has layers of underseal sprayed on everything .

I spray under my Jeep and also my Landcruiser with a mix of new engine oil and diesel at the start of every winter - on the Jeep you can see where it seeps right through all the spot welded seems that are such a rust and water trap.

 

I have been doing exactly the same thing with my stuff since the 1980s with no problems,your right about the new engine oil with the diesel, used oil will just leave everything black. This is a good practice, people should know that even if they park their pride and joy under cover, unless the garage is heated they will very likely suffer from damp in the atmosphere over the winter months. I spray the mix over and under, on any metal thats exposed to the elements, being very careful around such areas as the transmission handbrake and the brake drums.

[Big ray]

Just as a little extra advice...

 

If the underseal is Waxoyl based, Turpentine will remove it, if bitumen based, an old T-shirt soaked petrol will do a great job of the final clean up for you.

 

Nige

Diesel will do the same job on bitumastic, and is not so volatile, just in case your friends smoke ????? , I know that its oil based and will have to be pressure / steam washed after, but it might be better than a burned out motor. Just trying to be helpful.

[pockers]

Right with show season coming to an end i've started on worthy the jeep

So far I've found:-

an air powered needle scaler gets the loose rust n underseal off

Electric paint stripper to soften the underseal(only soften and avoiding petrol tank - taking that out later)

The just scraping with a pallet knife - the awkward stubborn bits I've used an old but sharp wood chisel works a treat

Then using wire wool or Brillo pad soaked in petrol give it a scrub and hey presto nice clean metal! ( obviously not using

Paint stripper n petrol at same time!)

It's a bit time consuming but is cheap and works

 

Can any one recommend a good chassis paint? ( I know hAmmerite is no good) and where to get it

[paulbrook]

I have found that underseal falls into 3 categories; the black stuff that has hardened off - needle gun or air chisel with a blunt flat end and not too much pressure - if you are lucky it will rattle off in big sheets. Second is the same stuff but softer, in which case a hot water pressure washer gives excellent results (works on the hard stuff too). On my website there is a spitfire (car) that was covered in the stuff including under the bonnet (www.rustytrucks.com) which was all removed in quick time with these two methods. The third stuff is a rubbery compound which is virtually impossibe to get off except with an air chisel.

 

If you want to put anything on the underside (and I doubt you do) other than paint use the overpaintable stonechip.

[pockers]

Cheers

 

Just want to paint the underside in a gloss black but obviously want to use something decent if I'm goin to the effort of re doing it.

 

Have tried several auto shops but they dont do it,

Seen several chassis paints on flea bay but not sure of the quality. Any one used any of these?

Any one reccomend a paint/supplier (I'm Surrey/sw London)

[Tony B]

Your local Dulux colour centre! I've one across the road in Orpington, they are great at matching paint samples and the range of both metalsheild and woodseal paints is superb, very durable stuff. The other stuff I've found very useful on a vehicle which you do inspect regularly is balck tin roof paint. Keeps the metal sealed but if anything does start it's easy to strip treat and repaint. Also very economic. What I would do is make sure you use a good quality primer, and two or three coats. Afterall that does most of the protection the top coat is just for show.

[pockers]

Cheers Tony

 

I was warned off hammerite as it's too brittle.

Will the metalshield be the same or will it stand up to the job?

 

Primer wise i was thinking red oxide - good? Bad?

If bad what's a good one?

 

Many thanks again

[Tony B]

I've found the Metalsheild to be as tough as, well tougher than re-enactors boots.:-D Same with the woodsheild on the rwear floor. Dulux do their own range of primers, they also have a large technical help libary. It also very good cover

http://dulux.trade-decorating.co.uk/products/index.jsp

Edited August 26, 2011 by Tony B

[paulbrook]

There is a very good company that advertise on ebay by the name of Jawel. Give them a go..

[pockers]

FoUnd jawel paints - went with their etch primer and gloss chassis black -

they gave some good advice and were good on prices too. Got the paint just got to finish the preparation work

 

Many thanks

[paulbrook]

Oh and these guys are excellent too:

 

http://rust.co.uk/?gclid=CKX-1cifkKsCFYUntAodDle9tQ

 

I particularly recommend the epoxy mastic paint.

[rambo1969]

Must admit, i'm not a fan of underseal, water seems to get behind it and then the rust starts.

When I 1st buy an mv, I go to the local commercial steam cleaners and have the underneath steam cleaned, I then scrape off any remaining underseal by hand.

I then paint/spray the underside with standard black gloss, b&q/homebase etc etc. I find black gloss stops the mud sticking to it.

I then pressure was the underneath about 5-6 times a year to keep and mud/dirt at bay.

Of all the landy's ive owned, I have only had to weld 1, and that needed welding when I bought it.

Thats what works for me.

[Tony B]

A lot of service vehicles are never undersealed anyway. Reason being the stuff burns.

[Pete Ashby]

Oh and these guys are excellent too:

 

http://rust.co.uk/?gclid=CKX-1cifkKsCFYUntAodDle9tQ

 

I particularly recommend the epoxy mastic paint.

 

I'd second that, not cheap but with good prep and the right application this stuff does what it says on the can, mind you you don't get long to get it on before it starts to go off and just like any two pack........don't leave it in the gun !!

 

Pete

[paulbrook]

A lot of service vehicles are never undersealed anyway. Reason being the stuff burns.

 

Paradoxically (bearing in mind the threat where they are being used right now) the latest MAN SV's are undersealed with a sort of waxoil type stuff.

[paulbrook]

In have just relaised that I have put 2 or 3 posts in a thread about paint.......

[Tony B]

Paradoxically (bearing in mind the threat where they are being used right now) the latest MAN SV's are undersealed with a sort of waxoil type stuff.

Water based stuff is preffered now, dosen't burn. The MOD approved Vactan is terrific rust killer /proffer/ primer. I was lucky enough to be given a load. It is very economic to use as about 1 1/2 litres will do a LWB Land Rover chassis twice over. I first applied the stuff to the Dodge about 4 years ago now, no rust has come through...yet.

http://www.paco-systems.co.uk/vactan.html

[paulbrook]

I too recommend Vactan - and also the thinner Fertan (I did my Mack chassis with that). But users of Vactan in particular should ensure that there is plenty of thickness (the recommendation is 60 microns which is pretty thick - at least three and probably 4 good coats) or else you will be disappointed.

 

Fertan can be put on with a garden spray and then you can pressure wash the excess off bringing off all the loose rust , it is brilliant for complicated stuff like suspension and springs and so on (in fact I am going to experiment with the underneath of a landrover soon). It is also supposed to be v ery good for spraying inside box sections. But unlike Vactan it needs to be overprimed.

 

I will ask those in the know, but I am pretty certain that the SV underseal is not water based. But then again I have been wrong before.

 

Off to watch some paint dry now...