Will underseal harm GRP?

[Loose Cannon]

I was wanting to freshen up the black in the wheelarches as it has been looking like orange and black rice pudding for a while. Bought some standard underseal/anti-drum type gunk from Autoparts then read on the instructions not to use on plastic parts; does that also mean Glass Reinforced Plastic parts?? The can says "contains Xylene" which I presume to be the nasty bit.

When I get a closer look at the original stuff on the car it looks more like paint than the trusty stuff you would have used on your rusting Mk3 Cortina. Should I chuck this in the bin?

[Jonathan]

Probably steer from that then.

I planned to do mine with some heavy duty black paint, either that or you can get some wax based sealants - try www.frost.co.uk

[Guest Troy Halliday]

I always use a product called Gravitex if that helps any.

[Loose Cannon]

Thanks for that, I looked it up on the net and it's made by the same people who make....POR-15! (Jonathan's lifestyle accessory )

[Tentenths]

Troy, do you use/recommend the aerosol or the brush-on version?

Edited June 14, 2006 by Tentenths

[Tentenths]

Ignore last posting... was confusing Gravitex with Gravigard

[Guest Troy Halliday]

Ah didn't think about that one I have always used an underseal Gun like this one Underbody Coating Gun. I would ask the supplier if possible as to his recomendations. I used it quite extensively on my car if you check out my Primer and Painting section in my photo diary you will see that I sprayed under the car, Bonnet , Boot and inside the car. I then sprayed over that with a Satin Black (makes it easier to wash of).

If you do get one of these guns mask up well as they can spray this stuff over quite a distance but it can be cleaned of paintwork with panel wipe before it dries quite easily. Oh and when it says ventilated area it means it. I was seeing pink elephants after I did my lot but then again I did do a fair amount in one hit. It always pays to buy a decent mask. It will last quite a while if you look after it and can stop almost all of the nasty chemicals getting in your lungs.

[nicksoldies]

I seem to remember reading somewhere that they used to underseal the inside of Elan and Europa wings to stop stones thrown from the tyres causing star cracks. It would be worth a call to the factory to confirm it is suitable.

There is an alternative called Stonechip which can be overpainted and forms a rubbery coating. It is best applied with a Schutz gun but you can buy aerosols. Whatever you use, check with the factory that it will be OK, they should know.

[markt]

Stonechips's my friend when I restore my cars... Haven't used it on the Esprit though, so can't vouch for 'stickability', but reckon it's a reasonably stable substance (I.E. no nasty chemical compounds)

I used it on a GT40 replicas body panels years ago. Haven't heard of any problems or reactions with fibreglass.

I'd say it's safe to use. Make sure the surface is sound, free of dirt, rust (that won't be an issue here) and spray-on. What I normally do is squirt on a coat of black enamel on top (the house hold stuff from any hardware shop). Gives a very clean look, repels dirt and soo easy to hose off. Finish has lasted for over 10 years and counting on one of my cars...

[Loose Cannon]

Thanks chaps, aforementioned shite is now headed for the bottom of the wheely bin, search on for "Stonechip".

[V8Esprit73]

I seem to remember reading somewhere that they used to underseal the inside of Elan and Europa wings to stop stones thrown from the tyres causing star cracks.

<{POST_SNAPBACK}>

Thats correct, they did and it worked very well!! Lotus also used to recommend that the same was done to the wings on a Seven to prevent them from star cracking also.

All the late Esprit's i've seen have the wheel arches coated in stonechip or similar from the factory, my V8 certainly does.

When it's knackered/ disturbed it peels off fairly easily to reveal the pink (!!) gelcoat.

Underseal won't harm fibreglass, just makes a bit of a mess and if you have to lie under the car on a hot day you'll end up covered in the stuff!!!

[Tentenths]

A year on and this has finally worked its way to the top of the list

Before I under/over order the paint anyone give any guidance as to how much will be needed for one coat on all four wheel arches? 1 litre enough?

Thanks

Edited June 5, 2007 by Tentenths

[russellbosier]

I did mine about a year ago. Quite amazingly I found some stuff in Halfords, cant remember its name but I still have the aerosol in the garage so I can find out tonight if you wish. It dries slightly rubbery, but not tacky, and from what I could tell appeared very similar to what was on the car originally. I did a quick touch up job with it, masking the outer edges and used newspaper to cover any areas that I feared may get overspray, and lightly sprayed round each wheel well - I didnt even need to remove the wheels to do this as there was sufficent room to get the aerosol in and spray. It blended very well in colour and texture with what was there originally and I was very pleased with the results.

[Tentenths]

Sounds just the job Russell. I'd be most grateful if you could confirm what you used

[russellbosier]

Hi James. Just had a look and it is black Hammerite Stone Chip Shield that I used. Comes in a large red coloured aerosol can.

[KENCO]

I have used duplicolor truck bed coating on many parts for many vehicles, just recently a fiberglass front spoiler on my 87 Ferrari Testarossa, came out great! Comes in black aerosol , and leaves a slight textured finish, very durable and tuff!

[Tentenths]

Thanks for that Russell (and Ken), much appreciated

[Loose Cannon]

Well, plucked up the nerve to bother Brian Angus with this domestic trivia, and he helpfully confirmed Lotus' product for stoneshielding the arches is called "Brushguard S1519" made by Dunlop.

Only found one supplier on the net selling in 5L cans, but a request for a price was ignored, so it's back to the Waxoyl product suggested before.