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Car Underbody Preservation

Mullardman

Mullardman

Moderately extreme...
I have an 04 2.0 L Honda Civic Type S which has only just gone over 51000 miles. It is plenty quick enough for me, returns reasonable mpg and has proven exceptionally reliable since I purchased it s/h about 3 years ago. A couple of tyres, brake pads, a single lamp bulb and a new exhaust are all it has had. If I can get another ten years out of it it could well turn out to be my last car.

Barring some ridiculously expensive and catastrophic failure of either engine or electronics, I can see this thing just going on and on.

Which brings me to my question. Whilst underneath the car at an surprisingly efficient and well run Qwik Fit place getting the exhaust replaced, I noticed a bit of surface rust here and there underneath. Nothing too dramatic, and much of it on components that could if necessary just be swapped out, but it got me to thinking... Would it be worth having someone treat the underneath of the car? If so what with? Waxoyl springs to mind. Would this be a) effective and b) worth the effort/cost?

Any views?

Mull
 
given road conditions in UK, salt and damp etc, undoubtedly yes.

Suggest you have a look around on the Retro Rides forum, and probably on Pistonheads. There are many alternatives. Getting the 'real oil' from those dedicated to keeping old iron running, or preserving it for future generations, should be worth the effort.

Speaking of real oil, I knew some old blokes back in the 80's who'd paint the undersides of their vehicles with old engine oil, drive them up and down dirt roads in summer, and let them bake in the sun. not environmentally friendly. little or no rust, though!
 
Waxoyl is fine and relatively cheap but it does require thoughtful application. It is no good just brushing or spraying it on, willy nilly.
It obviously works better the earlier in the life of the vehicle it is applied.
The surfaces need to be clean and dry (despite what is says on the tin) and things like brake and fuel lines need to be unclipped, coated and then clipped in again to avoid localised corosion that will make the rest of the exercise pointless.
Lips in wheel arches etc need to be fully cleared of compacted mud/dust etc. Waxoyl will not soak through it and will just sit on top.
I usually clean/ wire brush/pressure wash, dry, unclip, clean and coat and then replace or where it is not possible, metal brackets etc, force as much in and around with a brush and then spray over the top.
Done properly you will see no corrosion on brake pipes etc However finding someone who will do it properly and not just spray a quick coat on once your back is turned is a different matter.
Of course the real enemy is corrosion from within the body cavities rather than directly from underneath.
Waxoyl do a pump for cavity waxing but it is all rather hit and miss. However with illuminated pencil cameras for the pc for about a fiver you can have a look inside some of the sections if so inclined.
It makes the world of difference when spraying to make sure the wax is warm and liquid by standing the tin in a bucket of hot water for 10/ 15 minutes and keep shaking the tin every few minutes.
For brush application it is better cold but mix/shake really well first as it does separate in the tin.
Bilt Hamber also make a variety of excellent products for the same application.
 
I'm guessing you don't want to go mad with the cost of this, and I suspect that the problem is more the steel nuts and bolts, suspension arms etc.

I would suggest nothing more than using a spray can of wax, that you apply yourself simply by reaching under the sills/wheel arches.

I use Bilt Hamber spray on wax. I think it is called UC or something. I have applied it on my new car simply to avoid cosmetic corrosion of the screws/bracket etc.

I doubt you will see significant structural corrosion on your car, but a wax will definitely make it easier to remove fasteners etc. without having them rust into place.
 
I'd go for Rico's idea as using ones own oil in this recycling way is a decent green effort IMO
 
I've been using this for years:

http://www.amazon.co.uk/dp/B0043ZWCN6/?tag=pinkfishmedia-21

I'm careful not to breathe in the vapour when spraying (obviously). It's a little thinner than Waxoyl so penetrates as it goes on, but it stays there. Can't recommend it highly enough. Can also be brushed on where spraying is inconvenient/wasteful.
 
This site contains affiliate links for which pink fish media may be compensated.
Thin waxoyl with diesel, smelly but ensures it gets into EVERY nook & cranny.

Used Dinitrol (www.dinitrol.co.uk) on my Moggie, very good stuff and have a variety for different circumstances.

I've got an '02 1.7 VTEC Civic Coupe, 65K, pristine pretty much. This is now making me think that I should follow your lead! 2.0L......nice!
 
I've had tremendous success with Fishoilene, also smelly but gets into every nook and cranny, leaching in. However, it's not underbody protection. I've used in sills, doors etc. It's made from fish oil, as the name suggests. Once the solvents have finished evacuating (a couple of weeks), it's odour-neutral.
 
Don't apply anything that may prevent box sections ventilating/draining as they should by design. If you look closely, you will see odd holes or jogglesalong welded seams, these are to drain the electrocoat solution during manufacture and fulfill the same purpose in service. Cathodic electrocoat used these days is remarkably effective as long as the surface is not breached through scratches etc. But don't make any box sections watertight, as water will be held inside with inevitable corrosion starting from spot weld joints
 
Rico said:
Speaking of real oil, I knew some old blokes back in the 80's who'd paint the undersides of their vehicles with old engine oil, drive them up and down dirt roads in summer, and let them bake in the sun. not environmentally friendly. little or no rust, though!
Click to expand...
What do you mean? We all did. Every Mini, Escrot Mk 2, Crapi, they were all oiled up underneath to try and slow down the tinworm. Garages used to do it for a fiver. The snag with oil is it murders your suspension bushes. Waxoyl is kinder. One tip, other than what Steve Watkin says, is to avoid taking it out in the wet for a few days, otherwise if it's still soft the water spray will take it off.
 
stevec67 said:
What do you mean? We all did. Every Mini, Escrot Mk 2, Crapi, they were all oiled up underneath to try and slow down the tinworm.
Click to expand...
Thing is, most of that came for free via strategic leaks from the '60-70s British Sump/ Breather mk.1. Almost as effective as the vertically-split crankcase that did-for the British motorcyle industry... ;)
 
Just like to say a big thanks to all who have made suggestions.

I do routinely use a bit of old oil here and there. For e.g., I had the rear bumper off the car last year and noticed some surface rust on the steel cross member which supports it. 2 minutes with an old paint brush and a bit of old oil made that a bit less susceptible to corrosion.

But, I will investigate the various products suggested. (Dinitrol... that's a name I haven't heard for 40 years!!) More to the point I'll see if I can find either someone who will do the job properly, or somewhere I could access a lift and do it myself. I don't go in for rolling about under cars on the drive these days. Did way too much of that in the past.

Mull
 
stevec67 said:
What do you mean? We all did. Every Mini, Escrot Mk 2, Crapi, they were all oiled up underneath to try and slow down the tinworm. Garages used to do it for a fiver. The snag with oil is it murders your suspension bushes. Waxoyl is kinder. One tip, other than what Steve Watkin says, is to avoid taking it out in the wet for a few days, otherwise if it's still soft the water spray will take it off.
Click to expand...

down here, we don't have salt. at least, not on the roads. Where I live, it's pushed around in the air, by the wind. usually at velocities between 35 and 160 kiliometres per hour
 
Yes on Waxoyl, stopped corrosion dead on my Alfsud Ti back in the '80's. Probably had all the good stuff taken out now though due to environmental restrictions. If its surface rust underneath, then a coating of underseal may be more effective.

Good luck !
 
Wow a Type S low miler. Keep it!!!! I bought mine at 21,000 miles in '07, traded it in last year @123,000 having spent a huge £200 on repairs in 7 years. 1 fuel injector (+diagnostics, etc.) I absolutely belted round the place, with the original battery, original suspension, exhaust, you name it! The air-con was clogged somewhere (some twit removed the dust covers in its early life, but other than that all working brilliantly. Blew the odd bulb; I reckon the wiring to the headlight connectors wasn't marvelous, so spent about £20 on bulbs in the last few years.

Don't skimp on oil changes or spark plugs... or brake pads, 'cos it flies! I used the standard EBC pads and they were ace.

Oh, final joyous recommendation, Dunlop tyres. I used SP2000 [there are many close equivalents in their range] having tried many others. Awesome.

Sorry, bit off topic!
 
Thanks for the enthusiasm Linds. Yes, it is a nice car to drive and as I said, plenty quick enough for someone rapidly approaching septagenarian status. I change the oil and filter annually, which is about a 6000 mile interval. I use Castrol Edge. Not touched the plugs. Not even sure how to get at them. Just fitted two Dunlops and will fit two more before winter kicks in.
The exhaust broke just in front of the box. Not bad after 11 years.

TBH, I haven't seen another one.
 
Yup. My top tip is when spraying it in sills and other hollow sections thin it with paraffin or white spirit, then it seeps into cracks better. It is a bit hit and miss as Steve W says but I take the view that if you squirt it into box sections every year or so you'll get most of it sorted out one way or another. We aren't talking the last remaining Maserati Birdcage after all, if we were then you'd certainly be getting every last millimetre coated. Instead we're just talking about slowing down the inevitable corrosion on a car used regularly.

One final tip - I slather the brake pipes in grease, it's one less thing to fail an MoT on.
 
I had heard that old engine oil contains acids, and possibly other unwanted combustion by-products which might cause rather than prevent corrosion. Any truth to this?
 
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