Kristie-Anna

Ok.. this is my issue...it started with it blew the freeze plugs on the bottom of the block, bent the fly wheel. Had tht replaced, did a compression test and all 8 cylinders are at 125psi. So do I have a blown engine or what the deal?? I'm getting conflicting responses, honestly I dnt believe its blown otherwise my sister would b all over the place!! Mind you I had no signs of anything either, no mixtures, no smoke , nothing! Someone please give me an honest answer as what to do. I'm at a loss! 🥴

Gumby22

How many plugs were pushed out?

Did the block crack when the freeze plugs were pushed out? They’re supposed to prevent block damage but depending on the location and how the ice formed, the external block wall could still crack.

All cylinders being at 125 indicates the engine is functional, but even in an engine that hasn’t been through damage like this, all cylinders reading exactly the same is unusual. Did you mean they all read a minimum of 125? If so, what was the highest pressure recorded?

PNW NBS Z71

Besides the freeze plugs coming out, how many when you say "bottom freeze plugs", and the bent flex plate, a flywheel is for a manual transmission and very hard to bend, what problem are you experiencing? Is it running normal now and no temp problems or do you have any problems? It is almost unheard of for numerous freeze plugs to blow out unless you had very weak coolant and it got very cold. More info needed.

Little Bear

Just a side note, freeze plugs are not there to protect the block, they are there to plug the holes in the casting used to get the sand out after the block is cast. Typically by time the plugs are pushed out by freezing the block is cracked.

PNW NBS Z71

I have to agree but still don't know what the continued problem is.

Gumby22

In the interest of discussion & debate:

I remember talks about block plugs in several of my classes when I went to school for auto service. Every instructor (most with 20+ yrs experience) made sure to mention the intended purpose of the plugs was for block cleaning, not for protection from cracking; but they had all also seen cars where the plugs were pushed out without block damage.

I remember one instructor put it this way (not an exact quote) -

[Protecting the block is a fringe benefit of the plugs because they’re the weakest points in the block structure. Since every force we know of will always take the path of least resistance, the plugs should ​​​​​​push out of the block before the block cracks. But as with many things in the automotive industry, there’s a significant difference between theory and application.]

I agree with that, but I’m yet to see a block after freezing has happened, personally or professionally.

I lean towards the opinion that the conditions are what makes the difference. Again, in theory, a plug could be pushed out before complete freezing takes place, allowing liquid to drain out and relieve pressure inside the block. But that would also depend on how weak the coolant mixture is, the location the freezing started, and whether or not freezing occurred equally throughout the block as opposed to starting at the front/back/upper/lower portion and worked its way to the opposite side.

Kristie-Anna

In response to all ur Messages, which I thank you all for, I had no signs and I mean none of any mixture of any kind, no steam, nothing...I did a cylinder test on all 8 and they all came back at 125 psi....not one was less or higher...all the same...my oil is 50 psi, the block is in perfect condition...the truck was down by the beach, my whole underside is rusted, that most definitely helped the process of the freeze plugs corroding. Everything is pointing to the engine is fine. I'm not giving up just yet...my gut tells me its nothing too major...I love my truck and ive only had it 3 months now...so no im not giving up...granted numerous people have told me just trash it, call the scrap yard, etc....sorry I'm a female and a Taurus, the last person that told me not to do something I built an 85 cutlass supreme v8 into a show car w
/Hydraulics....it was so lowly couldntnput a soda can underneath it! Then of course it was stolen goi g to my 2nd show and recovered completely stripped in an abandoned lot!! Boy wasn't sad when it came back on the flatbed....anyways I so appreciate all the advice and comments...they help alot with my decisions. Any further comments I greatly welcome and appreciate. Thanx Again 🤪

PNW NBS Z71

Honest answer, sounds like the freeze plugs have been replaced and all seems normal for now. Drive it like you stole it and just keep monitoring all the freeze plugs. Whenever I was in my shops I would replace freeze plugs with stuff we called "Gorilla Snot", made by 3M, around the edge of the freeze plug and let them set up for 2-3 hours and then refill system. Before the freeze plug replacement I would get inside as far as I could and clean out as much gunk from the engine as I could.

Gumby22

Ok, I think maybe there’s been a misunderstanding about what actually happened here. It didn’t occur to me you used the phrasing of “blew the freeze plugs” until you mentioned in your second post about the steam.

Please clarify -

Did the coolant freeze and push some of the plugs out of the block?

OR

Did the plugs suddenly blow out of the block while the engine was running due to overheating?

If it’s the latter, there’s more to be considered and tested than just cylinder compression. Possible causes for plugs blowing out of the block I can think of at the moment:

1) The coolant was in horrible condition and was boiling inside the block.
2) Leaking head gasket causing excessive pressure in the block. Despite seemingly good compression, many head gasket leaks are not detectable using compression testing due to a variety of factors.
3) Lack of adequate coolant flow through the radiator due to inoperative/ineffective cooling fan, a plugged radiator or collapsed radiator hose, or a WP impeller that’s lost its fins due to electrolysis or sediment damage.

At the very least you’ll want to pressure test the cooling system when hot and verify the radiator cap is functioning correctly.

hi

Kristie-Anna

Ok, so obviously there is some clarification needed....here goes...
When I first bought the truck it had a slight overheating issue...I replaced the thermostat,(which there wasnt one), the radiator cap, flushed the system 2x, did an oil change, and was just about to do my front suspension when one day I was getting air, started the engine and grind grind bang, there goes the radiator fluid!! The freeze plugs at the bottom of the block blew, my manifold cover was missing unbenounced to me, so in turn they bent the flywheel...I NEVER HAD ANY STEAM, SMOKE, NO MIXTURES OF ANY KIND, HELL IT NEVER FULLY OVER HEATED!! SO IM ASKING WITH THE COMPRESSION TEST ON ALL 8 CYLINDERS COMING BACK AT 125PSI EACH, DO I HAVE A BLOWN ENGINE?? MY HONEST OPINION, NO I DONT...ALL 8 SPARK PLUGS WERE CHARCOAL BLACK...NO CRYSTALS, NOTHING... I JUST REPLACED TwO PULLYS THT WERE SHOT OUT, AND NOW IM GOING TO ADD FLUID AND CRANK IT OVER TO SEE WHAT IT DOES....🤭 wish me luck!!! Lol