RLS7201 wrote:
I didn't say it's common. I said there was some history. The engines I was involved with, hydro locked while sitting and destroyed them selves when the starter was engaged.
It's really a shame when a flaw is presented and brand name lovers are offended. I spent many years of my younger life as a automotive professional and may have seen more failures than hobbits.
Richard
I never accused you of saying it's common, but saying there's a history is pretty much the equivalent. And there is no history. I could care less about brand names. Every manufacturer has an example of some pretty craptastic designs.
But dude - hydrolocked while sitting and then destroying themselves? A starter motor having enough torque to bend crankshafts and break pistons? No. Wouldn't even have enough torque to break the teeth off the flywheel. The starter would destroy itself first. If filled with water they a) wouldn't fire (so no torque) and b) the starter wouldn't even begin to try to turn them over. Clicks like a dead battery. Been there, done that, got the t-shirt.
If it's running and water is suddenly introduced then you've got damage, but it's not happening from a head gasket. Not on a 454 or anything else. Sorry.
RLS7201 wrote:
454s have some history of antifreeze leaks from head gaskets and intake manifolds, causing hydro lock. Hydro lock can cause broken crankshafts, bent rods and broken pistons. I have personally been involved in the repair of two such cases of hydro lock.
Richard
I have never heard of this happening except on boats for obvious reasons. The 454 is a very popular marine power plant. I googled it to see if it's a common problem with the 454 or any other engine in particular. It just isn't.
There was no evidence of a head gasket leak on mine when the #3 piston came apart. You would have to have a massive, instantaneous intrusion of coolant in order to hydrolock an engine. Not saying it can't happen, but it's virtually impossible without very obvious signs of a head gasket leak over a very long period of time or some other catastrophic failure that causes the head gasket to blow. I had a Grand National that a shop apprentice stole after hours. He ran 30 PSI of boost through it street racing without knowing how to operate the alcohol injection system. The head gaskets on both sides blew in about 4 different places. But it didn't hydrolock. Beat the **** out of the crankshaft and main bearings but that was from detonation, not coolant intrusion into the cylinders. (yes I sued the shop owner, no I never got paid. Cost me $6k to fix it). But I digress....
The worst cases of poorly designed head gaskets I've come across in my shade tree mechanic life are on the older dodge inline 6s (like in the K-cars) and the Nortstar V8s. I've had several and none ever hydrolocked. They'd lose coolant at an alarming rate - but they'd burn it. Never hydrolocked. Ironically I did have an '86 T-bird with a nasty head gasket leak that I drove that way for years. It did hydrolock after going through a deep puddle in front of my house. Thankfully I wasn't going very fast. I was able to pull the plugs, crank it over a few times, put the plugs back in and start it up. I was only 15 minutes late for work!
Again, not saying it can't happen but I wouldn't consider it common and to say 454s have a "history of it" is just plain misleading.
hanko wrote:
The 454 is a great motor, i ran one well over 100,000 in my 91 pace arrow. The need some attention once and a while.
Jimmy, I wanted to tell you, i know where there is a MoHO just like yours for sale in michigan here if anyones interested
It is a great motor, I agree. I got my MoHo with 79k miles and the 454 had grenaded. I have no idea how it was maintained or whether it was a freak thing. There was so much damage there was no way to tell what happened but it looks like maybe a wristpin let go or a piston came apart. The replacement (used) 454 I put in it has been great.
Michigan is too far for me, but the old Allegros are well built and reliable. I use ours for quick weekend trips and tailgating - I'm afraid it's too old for long distance use.
