[sootieoil]

I am slowly piecing my 7.3 back together from a scored rear cylinder, that dumped diesel into my oil, so far I have a fresh .020 block and a turbo reciprocating assembly, that I still have to massage and assemble, I wonder if I fill the coolant passages half way with Hard Blok filler after I done the boring and honing, will it be an issue? Why did I wait till now to think of this???:icon_rolleyes:
always happens this way. since these engines are a little thin I don't see any problems doing this. anyone else thought of this? also anyone have a good set of bare casting heads?

 

[Squid63]

You would be losing a lot of cooling capacity. Hard blok is good for short runs, i.e. pulling or drag racing, but for going down the road, I think it would just lead to problems.
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[arthurgoboom]

I too believe you would lose cooling capacity. It probably would never show up in the water temp but the cylinder wall would get hotter, and possibly score the piston again. It'd be nice if you could get an 1/8" coating through the entire water jacket, but I don't believe it works like that.

 

[icanfixall]

The area this would work the best is the top portion of the cylinder. Thats where the most wall flexing takes place just after combustion. Not the lower section of the cylinder. Just run a good coolant and if it doesn't have the SCA in it add that. I dought you will ever have a problem with the cavation issue if you run Evans Waterless coolant. Its expensive but it works.

 

[asauer]

I'll third the opinion that it will overheat. If you figure on filling 50%, that doesn't leave much cylinder wall to coolant passage surface area to evacuate heat out of the cylinders. An 1/8" coating on the cylinder walls would be nice in theory, but again, you would completely remove any heatsinking abilities from the cylinders to the coolant. I agree with icanfixall- put it back together, and pray for the best the way it is.

 

[sootieoil]

I use Evans coolant already, I kind of agree that the top portion of the cylinder needs the strenght so a 50% fill might not be as beneficial. as far as the cooling goes I dont worry about that much, I never had problems after I used Evans, alot of the heat in the lower end of the engine is absorbed by the oil wich inturns goes into the cooling system via the oil cooler.

 

[cdnsarguy]

If your doing boring better do sleeves too..........

 

[sootieoil]

If your doing boring better do sleeves too..........

too late boring done did. now punched out .020, originally the block was purchased new in 1997 and I put 120,000 until now, always had a fresh change of coolant for the first 4 years. Evans the remaining years.
yea I know new sleeves would be better but I think I can slide. I know the history of the block since new.

 

[FreightTrain1107]

If your doing boring better do sleeves too..........

Yeah, no kiddin', I'm surprised the shop even punched that block out. They must not be too familiar with the 7.3 IDI. We had one years ago that was bored out and that motor died in 30K from stress cracking at the top near the deck.

 

[Justin C.]

I'm way behind on this, but there are a lot of engine builders who fill these blocks as much as 1/8" below the deck with hard block. They say it has no effect on daily driving and towing. It seems to me like it would, but I've heard several say you'll never know it was done.

Justin

 

[icanfixall]

Ok... Filling the block to a level 1/8th inch below the heads is really stretching the believeability issues. I would need to see this done and see it driving while towing a load up a grade in the summer.... I just can't see a filled block cooling enough. I am interseted though.. This reminds me of the Slick 50 adds. Run without the drain plug in place and not hurt the motor after slick 50 installed and drained out.:nono: