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Author Topic:   concrete - hard block ?
dluna
Dirt Freak

Total posts: 334
posted December 13, 2004 02:48 PM  
I just called my engine builder to remind him that I had not drained the water via the drain plugs before I took the motor out and up to his shop for refreshing and learned something new about my motor. I didn’t get to speak directly to the engine builder, but the guy I talked to told me it was a good thing I didn’t try to beat out the drain plugs on the block. I tried a few different things on each side of the block and finally gave up before giving back the engine. He said the block has “concrete” in it…then called it Hard Block later on. Can someone explain to me what exactly is going on here? He said there was a small amount at the bottom of the cylinder walls. I am a$$uming we he is talking about the Block Filler that I have read about here and there. He said I would not be able to remove the drain plugs. So, it’s a good thing that I ran plenty of Antifreeze through it before pulling it out.

I would just like some more info on how this “concrete” works and some pros/cons of it. Again, I’ll make the assumption that it is in place to help support the cylinder walls. Engine is a 30 over 383.

I never have claimed to be too smart on engines.

Thanks!

leapinlizard
Dirt Freak

Total posts: 402
posted December 13, 2004 03:11 PM  
Hard block is a name brand for filling the bottom of the block with a epoxy and letting it harden to concrete like hardness. The filler shorten the distance between major support structures and prevent's the cylinder walls from balooning or flexing. Drag racers often fill the entire block while street and circle track can't afford to displace the coolant so they often opt to half filling like yours. In short, it' a way to strenghten the block producing stiffer walls for power production.

autoshop
Dirt Freak

Total posts: 298
posted December 13, 2004 04:31 PM  
was it concrete or filler, If it was concrete it's a commonly called pour rock . It the same a fence post concrete it sets up the same you pour the bottom of the block with the rock and add water until the rock comes out the freeze plug holes then you knock in the freeze plugs and let it set until the rock hardens.

leapinlizard
Dirt Freak

Total posts: 402
posted December 13, 2004 07:25 PM  
Another interesting tid bit is you have to machine the block after filling because the filler of whatevertype will expand and deform the walls. Machining will correct this.

dluna
Dirt Freak

Total posts: 334
posted December 16, 2004 11:49 AM  
All I know is that the name brand was "Hard Block" or something similar. So…I guess I am still wondering the pros / cons of this stuff. I think I’ve found one con, which is that we can’t actually drain the block via the freeze plugs. Will using this stuff lead to cooling system problems? We finally got our system figured out halfway through last season. Now we run a thermostat and we typically don’t see much over 190 or so…unless I go “off-roading” and bend the nose piece down, blocking the air flow. So I guess it isn’t causing too many cooling problems, but I’d just like to hear more about it.

Leapin, you mentioned the expansion of the walls during fill, but how does the filler react to the many heat cycles that the engine goes through?

THANKS

juliaferrell
Dirt Freak

Total posts: 370
posted December 16, 2004 08:50 PM  
www.hardblok.com

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