Hard block vs girdle vs both

boss300 · Oct 8, 2022

Hello all,

I currently have a 99 7.3 with 250/100’s, s369sxe, cryo’d forged rods, and otherwise stock bottom end. It just broke the crank somehow (haven’t pulled down yet to inspect) and am going to build another engine. I want to upgrade the bottom end and was wanting opinions on using a girdle with main studs, hardfilling the block and using main studs with no girdle, or doing it all. I am concerned the hardfill will hurt my cooling capacity as this truck still tows a 37 foot travel trailer through the Carolina’s and Tennessee. Is a girdle with main studs worth it without the fill in order to keep the best possible cooling? I don’t plan to make over 600hp anytime soon.

Thanks

ToMang07 · Oct 8, 2022

I'd stick the the girdle if you're planning to tow.

Sent from my SM-G991U using Tapatalk

6.0 Tech · Oct 8, 2022

I agree, wouldn’t fill a street or tow motor at all. I’d do the girdle and studs together. Don’t think it will help with this current issue you had, haven’t seen many broken cranks on powerstrokes at all. That’s an odd failure to have happen.

Sent from my iPhone using Tapatalk

boss300 · Oct 8, 2022

Does the hardfilling help with main cap walk? Or is it just to keep the block from cracking under high loads?

As for my crank, I was in the slow lane on the interstate going 65 and it got really loud and started knocking and shaking. I had to go 2 more miles to an exit and it made it to a parking lot of a Harley shop. It never lost oil pressure on the dash idiot light gauge. Now I can move the balancer back and forth several degrees and the flex plate end dosent move until I take the play out of it and then it will spin. Don’t really know what to expect to find when I open it up.

Powerstroke Cowboy · Oct 8, 2022

I know of guys that DD and tow with the block partially filled. They say the key is to not fill it all the way up, as in keep it down below the deck by about two or three inches since that's where most of the heat is generated from the combustion.

I have no experience with it. But, I will be doing the same on my engine when I rebuild it. Partial block filled (have the stuff just waiting for the right time) and wither a girdle or a bed plate.

The idea (some of it that is) behind filling the block is to keep the block from flexing. That will cut down on the main caps walking and the block from cracking as well. Plus it will be better on the crank and main bearings as well.

6.0 Tech · Oct 9, 2022

On our last race truck, we were running a completely filled block, but had water running thru the heads. Jared from kill devil had told us to never exceed 150degrees in it, as the expansion rate of the pistons/block/fill were so different we could hurt it easily. Granted this was completely full, but I still think I’d be very Leary of driving any sort of distance on a partial fill

Sent from my iPhone using Tapatalk

Powerstroke Cowboy · Oct 9, 2022

I understand your concern. That was mine as well till I was told its just fine. It does seem to completely against what common thought would be.

Filling the block 2 inches from the deck was and might still be a common practice of swamps, even for DD pickups.

lincolnlocker · Oct 11, 2022

Or tame down tuning a little bit.

Racer71 · Oct 11, 2022

I ran short filled gasser engines on street for a few years. The filler is mostly to help with keeping the cylinders round and strengthens the mains some. In the sbf world before aftermarket blocks were readily available a main girdle with studs and a short filled block was the norm. I wouldn’t tow a bunch that way but diesels cooling demands are different.

lincolnlocker · Oct 14, 2022

Fill to the freeze plugs and bed plate/girdle it.

Powerstroke Cowboy · Oct 14, 2022

lincolnlocker said:
Fill to the freeze plugs and bed plate/girdle it.

That's going to be my approach, I will keep it below the plug used for a block heater though.

lincolnlocker · Oct 14, 2022

Powerstroke Cowboy said:
That's going to be my approach, I will keep it below the plug used for a block heater though.

Perfect

boss300 · Oct 15, 2022

There is a how to thread with pictures over on power stroke nation. That write up has it being filled halfway up the water pump ports. I was thinking of filling to the bottom of those ports so water pump flow is not restricted but would that put enough in it to make a difference? I’ve never paid attention to how far the water jacket goes below those ports.