Engine cover finish

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pkempen
Posts: 3
Joined: 16 Jul 2024 05:43
Location: Looe/England

Engine cover finish

Post by pkempen »

The fuel tap on my 31/2 Sport has been leaking and the fuel has taken the black finish off the clutch cover, which was a surprise! I was thinking of getting the engine covers powder coated. Any had any experience of this, or know what the original finish was?
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Daddy Dom
Posts: 519
Joined: 16 Nov 2006 19:48
Location: Auckland, New Zealand

Re: Engine cover finish

Post by Daddy Dom »

I had mine done in random satin and it looked great.
There's no sense in labouring over any original finishes on these bikes as they vary far too much.
DD
MRC 3082½
3potjohn
Posts: 1335
Joined: 02 Jun 2007 13:58
Location: Devon

Re: Engine cover finish

Post by 3potjohn »

Petrol seems prone to eat away at anything. One of mine has a black finish which had some bubbling/pitting. I have sprayed that case with black gloss heatproof paint- either Halfords or Simoniz . Looks fine but am very careful to avoid spillages.
Guess the coating route is more resilient. I could get mine redone at “bloke down the road” who left some blast material on a cast wheel spoke last time.Good with gates though.
bikercarr
Posts: 4
Joined: 20 Apr 2024 19:09
Location: Tavistock England

Re: Engine cover finish

Post by bikercarr »

The only way that you are going to get a fuel and oil resistant coat of paint is by applying 2-pack which uses 2 ingredients (as the name suggests) - a resin and a hardener.
Every other kind of paint (including Halfords and Hycote Petrol Resistant paints) uses a hydrocarbon variation of petrol as a solvent which evaporates after application. Obviously when petrol is re-introduced it 'melts' the paint.

If you don't want the hassle of buying separate 2-pack paint and hardener it is possible to purchase 2-pack (2K) paint in a can - but in my experience make sure that you buy the kind which has a ring-pull to mix the 2 ingredients. The other 2K paint in a can (with no ring-pull) claims that it air dries but I have had no success with it - a waste of money.
Personally I have used one pack paint - Simoniz Tough Paint in Satin Black as it seems to offer more protection than other one pack paints and won't rub off if your boot scrapes against it. It's cheap enough and there's plenty in one can to do both engine casings - keep a bit to overspray later if petrol does find it's way onto it. I use Simoniz etch primer first.
mad muller
Posts: 192
Joined: 19 Aug 2011 11:29
Location: liverpool, england

Re: Engine cover finish

Post by mad muller »

When I rebuilt the engine I had all the casings blasted to remove all the black factory paint finish which looked awful to be honest and left it all alloy which is not correct I know for the year but it looked to good to paint in my opinion , if it's originality your going for maybe it's worth taking to a decent spray shop and go for what they use on the jap bike casings it will prob stay on a lot longer than modern rattle can water based piss they call paint nowadays acrylic etc , I know cost dictates and as you can prob guess iam not a fan of painted engines but prob a more long term fix.
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Parker3865
Posts: 145
Joined: 13 Sep 2022 18:16
Location: Brentwood
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Re: Engine cover finish

Post by Parker3865 »

Cerakote?
Morini 250 2c rebuilt from a box of bits.
rossguzzi
Posts: 457
Joined: 23 Jan 2019 14:21
Location: Perth W/Australia

Re: Engine cover finish

Post by rossguzzi »

Possibly VHT Caliper paint. Spray on then bake. If it can withstand brake fluid ......
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