Finally started to build "Portalcat" and have a very nice Tomcat frame on a very good chassis. I am cutting off all the crap and beefing up a few bits and thought whilst I am at it, why not seal up all of the surplus holes. This will stop crap getting in but will prevent it from drying out from condensation etc. Is there any scientific reason for those holes to be there?

Would the expanding builders foam stop condensation if you filled the chassis up with it? Or would it add alot of weight on a big scale like this?

Sounds like a good idea to mee. Would stop crap getting in.

In my mind it will cause the chassis to rot quicker, as any moisture will get held against the chassis rails and not dry out.

Martin

I used to be a boat builder and can confirm mpb is right. The stuff acts like a sponge and will stay wet for a very long time. You would need closed cell foam and I don't think you can buy it in liquid form so unless you fancy mixing a few hundred thousand polystyrene beads with glue and pouring it into your chassis I'd forget this idea.

Having seen how that foam traps moisture around gas flues I'd say no as well...

I thought about expandable foam, when I first did my chassis but decided against it for 2 reasons

1, the moisture trap

2, how would it react to any future welding of the chassis,

it would be interesting to see how much a chassis weighs when nice dry/empty and uncompeted or dunked regulary in mud and water, and say in a couple of years time, when like my chassis no matter which hole in the rails I poke a srewdriver or similar they all feel full of wet mud.

Another point worth noting is that I'm in the process of breaking a 200Tdi Disco but before I do we are going to do a good muddy playday before weighing in the body, if its wet through and full of mud underneath it could fetch more than it did when it was new with scrap at the price it is, leave the window open, get the seats wet.

I seriously think Alan leave it alone, or perhaps put more holes in where a lance could be inserted to wash out the muck, if its full of mud and weighs a ton it will help it land on its wheels if you roll it.

See you soon mucker

I once had a leaf sprung 1964 Austin Gipsey that started life in the Uk and was driven overland out to Australia through varying damp,humid and salty environs. The chassis like a landRover was constructed from thin sheetmetal but without any holes. Although the bodywork virtually rotted off the chassis the chassis itself was structurally sound and rustfree.Way back when Leyland aquired both Austin and Rover they should have rationalised and fitted LandRover bodywork onto Gipsey chassis and mechanicals.
Bill.

if you waxoiled the inside of chassis and covered the holes you'd keep the mud and moisture out
and should last

Why noy just galvenise it?

When I had the 90 I drilled them out to hose pipe size. After playing parked on the drive which had a slope and washed out front to back.

You could seal the upper holes and just leave the bottom ones with a removable style of wading plug?

Mark

I agree, if your going to the expense of portals, and a tomcat frame wouldnt it be worth getting it galvanised?

The chassis and frame are built and needs a lot of work welding cutting etc as the build progress's. I think I will just weld patches over every hole to seal it completely.Maybe leave a plugged hole at either end so I can fire some oil in there when it is finished.

yeah, just make a big bung at one end, then spray in a mix of diesel and wax oil with a paint gun, works a treat

i'd leave holes in it so **** can be blasted out, imho, regardless of how well you seal it, **** will still get in.

anyway, how is the truck running? get home from the 90degree ok?
si

The chassis on my truck now has all the holes and there is about 6 mm of crud in the bottom of the chassis rails, no way of really getting that out. Adds weight and increases corrosion.

Truck is good, both are running better thanks

How about welding up everything, and adding the drain plugs suggested above, so that if anything does get in it can be removed / flushed clean and also drilling and tapping for a couple of breathers to stop condensation? could run them up with the other breathers nice and high, should be good.

Allan get yourself a drain cleaner for the pressure washer
easy as anything to clean chassis out

http://www.amazon.co.uk/Karcher-Drain-Clea...m/dp/B000HOJ9BK

I suppose it depends on how well you can seal the chassis. So many mounting points and holes etc, I'd lean towards tony's suggestion. I'm also made up cos I have a drain cleaning nozzle for my jetwash! Roll on the weekend, good thinking that man.

a 20mm hole in the rear x member is perfect for cleaning the entire chassis rail

ps recognise this Mr Kemp?

Hi Allan

How about seal it totally, in front and rear weld in some off them the big screw things from oil drums I think they are 2" diameter, just cut them out off scraped drums, then you can remove them for inspection and you can give it a good spray off waxoil inside.

Just my thoughts.

Regards

Ole.

i'm still toying with the idea of brazing some metal hose pipe fittings to the front and rear of the chassis legs and widening a couple of the drain holes in the chassis legs for drainage - so after a good play i mud i can just clip a standard hosepipe onto the fitting and turn the tap on.
go for a coffee and ciggy and come back and swap the pipe to the other chassis leg and jsut leave it to run through.

Can you really get a drain cleaner the whole length of the average chassis ?

What about the strengthening plates inside the chassis rails etc.?


I would have thought closing all unnecessary holes is a good start.
Before you have a truck attached to it, seal all remaining holes that will be used in a temporary fashion (Duct tape / mobile welding on a roll type thing) and then pump loads of thinned / warm waxoyl into the chassis rails from the front.... (May be wise to do one rail at a time..)

Generally move, jiggle, invert, shake, rotate the chassis to try and get waxoyl contact with all internal areas..... Then drain excess waxoyl....
(I would suggest using something like Niges cat to wipe off the excess on the outside if any ooozes out.....Oh and definitely use someone elses drive / land...)

Do same to other rail... Allow to cool / set and build truck around chassis.

All holes will be either sealed by you or sealed with bolts through / to chassis rails so minimal water should get in, and if any does it will probably evaporate before it penetrates the waxoyl coating.

Or fit a very small jet engine to the front of each rail.. When the interns get wet, fire up the jet engines to cook the chassis rails from front to back, drying any wet areas in the process....


Neil

Neilyes easily there are no plates blocking the chassis
the drain cleaner hose fires the water backwards as well as forwards this drives it along
I clean the 90 chassis regularly it really is simple but effective

Nice to know that Tony.....

Great idea too! LOL


Neil

Alan,

Unless you can make the chassis rails airtight, you will get condensation in the rails and they will rot from the inside out.

Given Land Rover's build quality, I wouldn't put a lot of money on all their welds being airtight......

I would follow Tony's lead personally.

How things change , I had just resprayed it after fitting bling Mach 5's and wider aluminium wheel arches. Evolution, its a wonderful word..

I'd leave the holes on the bottom, My first landy was a S1 Trialer. I rebuilt it when i was 16. one chassis rail was completly rotten from front to back (the bottom and a third of the way up the rail ) The other was fine ! when i stripped the chassis down and cleaned it up for repair i found the main chassis drain hole on the rotten side had bin welded over !!

You could pipe your engine breather into the chassis so any burnt oil vapour will condonsate in your chassis !

Paul