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To Decrud Or Not To Decrud.....

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78MGB

78MGB

Jedi Hopeful
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Greetings,

Looking at the ole engine bay and underneath the MGB, I ponder , is it best to decrud or not decrud the machine? Not the worst, but there is oil etc. Can find the grease certs with ease, but there is this "film" /ubbthreads/images/graemlins/wink.gif on the engine and underneath. To do so would mean some sort of undercoating. A PO did an undercoating I assume, but it is not everywhere. Another example why prep work is 90% of a job well done perhaps.

So, leave it alone or decrud, that is the question to the group. If you say decrud, what is the best method to do this and what to do with the decrudded (is that a word scrabble fans) underside? Thinking about a Simple Green soaking, rinse, and undercoat in a can. How long should I allow for drying before spraying?

Thanks for your input.
 
I'm not a fan of undercoating. It's great for a while, but when it gets old it hardens and cracks. That's when water gets trapped in there and feeds the rust maggots. You don't know what's going on until you fall through the floorboard one day.

I'm definately a fan of keeping the engine bay clean. Let it go too long and it's impossible to shine up again. I use minimal cleaner and water with a couple different shaped brushes to scrub away the grime. Better to scrub more than to flood the engine with degreaser. If it's really bad you just don't have a choice.
 
Depending on the extent of crud, a simple cleaning and undercoating works well.
Undercoating is like any other topical covering it will age and crack but if you keep it clean and intact it works well.
I use a pressure washer with the PSI setting reduced to clean off the undercoating and then inspect it while it's drying. If I find any bubbles in the metal, I clean it off, repair and recoat.
They only started using salt on the roads around here in the last decade so the accumulation of road grime and salt on the underside is not as bad as colder climates.
Every car I've rebuilt from the north or east has had underside damage from bad to horrible if it had undercoating or not.
I use a NAPA labeled undercoating that I find works quite well at protecting the underside and lasts a good amount of time.
I've bought several Fred Flintstone cars in the past (I presently have a 74 Nova with a steel plate where the hole in the driver side floorboard is but it was just a rice rocket killer that I bought for parts) and I've always put undercoating on the wheelwells and critical seams on the underside at the least.
 
Hmmm...good point on the undercoating. So, what is your #1 way to protect the underside. Assume you are putting on something like Waxoyl and wonder how often you would apply.
 
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