Help! I may have cracked block/head/?

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GJCruiser

GJCruiser

10 Year 15 Year
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under Pike's Peak
This was first posted in the 55 section where one can see the progress on my 55 restomod build. I'm looking for ideas as to how to go about assessing what I believe may be a freeze crack somewhere?

Here's the painful story.

I'm pretty sure I cracked a head or a block or a ? Please help me gather an investigation sequence. Man, this is painful. If you've been following, you'll know I've not been on here for a while. After the deaths of two family members, we moved back to CO, (Springs) to be nearer to two daughters. Long story- not good- took two years of wife's and my lives. We're recovering.

I have come so far on the 55--new floor, brakes, axle, steering, bearings, AC prep-this thread is a part of it. This morning went to back it out of the garage where its been since we moved into the new house. Went to check fluids and found radiator low and started refill. Something's not right, radiator is not filling, floor is dry. I check oil to discover I'm filling the crankcase with water!

I had been driving it around Biloxi to gas stations, shakedowns, etc. on pure water. Before moving last October, I topped off rad with 50/50 mix, probably 1/2 gallon. Trailered the 55 behind U-Haul. You may remember the late October snowstorm and following cold. We we're in OK the worst night parked at motel-got damned cold. Lost all plants in back of truck. When we got keys to new place in the Springs, I backed the 55 off the trailer and parked it in the garage (unheated), where it sat untouched untill this morning.

We had two -15 nights in January but I don't know how cold the garage went to. I'm thinking it froze sometime then? Could something really have cracked internally? I'm in shock.

Short of a complete teardown, anyone know of any external investigations/ideas? Color me sick.
 
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GJCruiser said:
Short of a complete teardown, anyone know of any external investigations/ideas? Color me sick.
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There are a few freeze plugs in the block and head, theoretically, they will pop out before the block cracks. Look at those plugs, If they look normal I'd start it up and see how it runs, look for new leaks...
 
Pighead said:
There are a few freeze plugs in the block and head, theoretically, they will pop out before the block cracks. Look at those plugs, If they look normal I'd start it up and see how it runs, look for new leaks...
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I'm crawling under it and looking around. Looks good. Would not a bad freeze plug sent coolant onto the ground. The floor is bone dry.

More thinking. I'll bet the freeze happened the night outside in OK. I only drove it 40 feet from the trailer to the garage in Nov. I didn't notice anything different then and it would have taken the engine running to pump the coolant into the block, correct? I'm thinking the coolant couldn't travel just sitting in the garage?
 
I would use an antifreeze coolant system pressure tester to pressurize the radiator, pinpointing potential leaks. You can also run low pressure compressed air and use a stethoscope to help detect and pinpoint leaks. Simultaneously, I'd do a compression check of the engine to assess its overall health and identify or rule out any underlying issues. Upon detecting low compression in a cylinder, I'd pressurize the radiator to confirm if pressure is infiltrating the combustion chamber through the coolant system.
 
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Does this rig have an oil cooler.? That would be my first check. In any event dump the oil sooner than later. If the oil cooler checks out or if it doesn’t have one then…..
Drain the oil, leave the drain plug out and again, attempt to refill with water. If you see water coming out of the oil drain plug, then there is something more serious than a freeze plug.
If you had water running through the engine, your next step would be pulling the head….I’ve had head gasket leaks, that have filled cylinders but none that made it to the oil pan….
Anyway once the head is off and still no visual on a leakage source, pour water through the open block and if you still have water draining out of the block…..probably an internal break.
But oil cooler first, if installed.
 
If by adding coolant to the rad and it fills the crankcase with no pressure behind it while filling sounds pretty catastrophic. If the rad can be filled, then probably a pressure tester would be a good start along with a compression test and a simple cyldr leak down just by adding compressed air to an offending cylder and listen thru the crankcase, carb, rad to ID where it's leaking.
 
numby said:
Sorry but probably this^^^^^.

Your coolant mixture at 50/50 is not enough to prevent a cast iron block from cracking. 24-48 hours is all it takes. Freeze plugs do not always blow first. Ask me how I know :rolleyes:
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So where was the crack after it froze?
 
He states the cooling system was filled with water. Then found it was low and then tried to fill it with a 50/50 mix of coolant and water. He only added about a 1/2 gallon. Certainly not enuff to protect it from freezing. Sort of shutting the door after the horses had already left. You might pull the pan then have someone add water while under the engine and see if the water is leaking from the blk.
 
Thanks for the reponses. Yes, I admit there wasn't enough anti-freeze. I drained oil/water mix from crankcase so I can confirm water added to rad is going into crankcase without pressure Pulled all plugs ran compression test (@6200 feet)---130,85,110,95,110,110. I cannot fill rad. I do have an oil cooler, what is the failure mode there?
 
The oil cooler is on the side of the engine and uses coolant to cool the oil. I would check that 1st. If the cooler checks out OK, then you could have an internal crack in the crankcase. As I mentioned, you could pull the pan and watch underneath as someone adds water to the rad.
 
85 and 95 are a bit low, but I doubt that is related to the coolant issue. I’d stick a coolant system pressure tester on it next to see if you can pinpoint where the coolant is entering.

Where is the oil cooler and does it have coolant circulating through it? If so, pull those oil lines and see if coolant comes out of those ports.
 
I’ll post here as well in case you miss it in the 🐖 section.

High possibility you lost a freeze plug behind the rocker arm cover. That would dump coolant straight into the case and leave cylinders dry.

Photo stolen from mud:

1712696537907.webp
 
Mark Jennings said:
So where was the crack after it froze?
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It was a small block Chevy with iron heads about a month after having it re-rung. Two days at about 0º with coolant mixed for warm weather did it in. Cracked right across the lifter valley under the intake. Took me a while to figure out what was going on.

Edit: I was thinking there was a freeze plug behind the pushrod cover. With the way the water flows directly through the OP may have gotten lucky.

Not the same engine but the point is there's just no give in cast iron. I'm not quite old enough to remember the days before anti-freeze but my family dealt with with cars in the early part of the last century after transitioning away from horses. You drained your engine every night.
 
FJBen said:
I’ll post here as well in case you miss it in the 🐖 section.

High possibility you lost a freeze plug behind the rocker arm cover. That would dump coolant straight into the case and leave cylinders dry.

Photo stolen from mud:

View attachment 3603050
Click to expand...

FJBen said:
I’ll post here as well in case you miss it in the 🐖 section.

High possibility you lost a freeze plug behind the rocker arm cover. That would dump coolant straight into the case and leave cylinders dry.

Photo stolen from mud:

View attachment 3603050
Click to expand...
Of the various possibilities, this one looks like one of the easiest to verify and fix. Fingers crossed this turns out to be the case.
 
FJBen said:
I’ll post here as well in case you miss it in the 🐖 section.

High possibility you lost a freeze plug behind the rocker arm cover. That would dump coolant straight into the case and leave cylinders dry.

Photo stolen from mud:

View attachment 3603050
Click to expand...

I had no idea the those core plugs were there. Hopefully that's the problem.
 
Physicians are trained to utilize the “differential diagnosis” as a method of determining the cause of a symptom. This approach lists all of the possible causes and seeks to rule out as many as possible to determine the sole cause. Fundamentally, mechanics use a similar method. But it often makes sense to rank the possibilities in terms of difficulty and cost starting with the least expensive and easiest working toward the most difficult and costly.
 
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