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engine rebuild

Posted: Wed Sep 28, 2005 4:51 pm
by diescher
Hi

I´m restoring my porsche 911 2,4 S (1973). And now I´m beginning to rebuid the engine. I have a question.
What´s the better way to clean the engine case? Can I blasting the engine case? What do you recommend?

Regards

Posted: Wed Sep 28, 2005 5:06 pm
by willbrown
Good luck with the re-build :P

Do you mean detailing the case (exterior) or is it split and you need to clean the internals? Either way if it's '73S the case will be magnesium so treatments are limited.

Posted: Wed Sep 28, 2005 5:16 pm
by diescher
I mean the exterior and the internals.

thanks

Posted: Wed Sep 28, 2005 5:27 pm
by willbrown
Blasting doesn't seem to be a good option. Ultrasonic may be the way to go.

Check out this thread for more info: http://forums.pelicanparts.com/showthre ... +crankcase

Posted: Wed Sep 28, 2005 5:27 pm
by davidppp
hello Dieter.

DO NOT blast the case.

It is literally impossible to ensure removal of all the tiny fragments of loose metal and highly abrasive oxides which result, not to mention the blasting media them selves..

Even blasting with anhydrous salt crystals, (itself easily dissolved out of course) leaves the same problem with the residues..

If any deposits on the metal are not removed by normal solvents, and medium high pressure water, you can forget about them, as they will not come loose and damage your new engine..

Loosening them with media blasting is creating a problem..usually for purely cosmetic reasons.

If the case is pretty clean internally, its well worth trying to keep it that way, as muck is more easily introduced then removed..If the case is full of gunge inside, you should remove all the oilway plugs and use long soft brushes down the oilways with solvent..

You will need to take great care when doing the oil bypass mod, plugging all holes...

The most common thing is people forget to remove and properly clean the oil spraybar in the cam cariiers..these are surprsingly often blocked..and its not a bad idea to take off the cam covers on first startup to check them..makes an awful mess..but gives peace of mind..

Kind regards
David

Posted: Wed Sep 28, 2005 5:33 pm
by Gilbert '71 T
As everyone else says DO NOT blast the insides as the beads(sand) will stick to anything oily and that could really ruin your day, then you'll need a soak tank big enough and full enough of something like Piston Kleen to entirely rid the case of beads, and the chances are you would have buggered the case by blasting the anyway

If the case is split then just use a very good de-greaser for the whole thing. if it's not split then I'd be inclined to be synical about it and just clean the exterior parts that are visible with de-greaser (just the underneath then)

Things like camshaft towers, end covers, fan/housing can be blasted and look good if there's not much corrosion, I've done mine (valve covers are new though) soaked them in some carbon remover/sprayed with wd40 afterwards and they look pretty nice. note that I didnt bother with the case as it's not visible, Zinc plating is a nice touch as well for all the other bits and bobs.'Bling'

Image

Good luck and let us know what you do.

Posted: Wed Sep 28, 2005 6:24 pm
by Mat2.2t
Thats gonna be one nice car!

Posted: Wed Sep 28, 2005 8:47 pm
by Barry
Darren, I'm sure I can see a gudgeon pin circlip down that dizzy drive hole?!? Just split the case and have a quick look would you :P :wink: .

Looking good!

Posted: Wed Sep 28, 2005 10:04 pm
by Gilbert '71 T
Barry wrote:Darren, I'm sure I can see a gudgeon pin circlip down that dizzy drive hole?!? Just split the case and have a quick look would you :P :wink: .

Looking good!
but it's holding the case together :lol:

Sorry diescher, hijack over