MTFCA Forum

I know it's a little late for this question but if you remove the elbow from the side of the engine block will that allow all the water to drain out, or at least enough that you don't have to worry about cracking the block when the temps get below freezing?

Just before I picked my engine up from the rebuilder last November, he ran it on a dyno, hooking a water hose to it for cooling. Other than letting the water drain out when we disconnected it and loaded it on the trailer I didn't do anything else to it. About the time it got really cold I broke my leg so nothing was done to the engine after that. With a lot of time on my hands lately I got to thinking maybe I screwed up by not blowing it out with compressed air.

Today I got into my barn and shop for the first time since the accident. I inspected the frost plugs on the engine and they were all in place. Stuck my finger in the side outlet and it was dry. Should I be concerned?

I have a new radiator which has not been installed so there is nothing to worry about on that end.

Tim, glad to hear you're mended !! far as I've ever reckoned, the Model T block will be safely drained when the system is completely drained. No need to remove the inlet casting even. Could be problematic if the engine was laid on its right hand side before everything drained out, but I'd be willing to bet more than I can afford to lose that your block wintered through just fine.

In most situations, small amounts of water with plenty of surface area will not break things when frozen. If the water has room to expand, like in an ice cube tray, no damage occurs. If enclosed with little air space, that’s when things start to go bad. For an operational engine, the inlet and outlet freeze first due to their exposure, effectively sealing the block and setting one up for damage. A loose engine or bare block that has been “tilt” drained should have no issues.

Keep crankin’,
Eric

I always drain the car hot any water left will evaporate with the heat in the block we have done this since 1960 with no problems

The "frost plugs" are not to protect the block from freeze expansion, they are welsh plugs used to close off the block openings from the internal mold access passage.

Sounds like I dodged the bullet this time... I'll know for sure when I fill it with coolant It was hot when it was drained and did sit for a month or more before temps would have gotten below freezing. All to the good I guess.

I didn't know that about freeze plugs...I always learn things on this forum. Thanks!

While it's true the plugs were a production feature, it's also true that they will get pushed out if water freezes in the block - whether it saves the block from being cracked is a wild card. Sometimes they escape damage, other times not.