Hydrolock.......explained
08-14-2006, 10:20 PM
#1
Three Wheelin'
Thread Starter
Hydrolock.......explained
For anybody wanting to know about hydrolock and was afraid to ask, lemme 'splain:
When any liquid enters the combustion chamber and fills the chamber, the piston will not be able to push up against it during a compression stroke (when both intake and exhaust are closed and holding pressure against an incoming piston) because liquids are non compressible. So, it essentially locks the engine. Of course, the usual is to have a mixture of fuel/air that IS compressible. Usually see hydrolock in water pumpers if somehow water leaks into the chamber (bad head gasket), or if car hits a high water spot and submerges to a point where water pours into the carburator or fuel injection (aspiration). If the engine is forced to turn, it will bend the connecting rod or anything else.
Jaime
When any liquid enters the combustion chamber and fills the chamber, the piston will not be able to push up against it during a compression stroke (when both intake and exhaust are closed and holding pressure against an incoming piston) because liquids are non compressible. So, it essentially locks the engine. Of course, the usual is to have a mixture of fuel/air that IS compressible. Usually see hydrolock in water pumpers if somehow water leaks into the chamber (bad head gasket), or if car hits a high water spot and submerges to a point where water pours into the carburator or fuel injection (aspiration). If the engine is forced to turn, it will bend the connecting rod or anything else.
Jaime
08-14-2006, 10:57 PM
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The question is? How did you find out.. With the starter or by turning the engine over by hand. Hopefully not with the ignition switch..
08-15-2006, 01:07 AM
#5
Drifting
Jaime, sorry to hear about your misfortune, you've had quite the ride lately 
Hope it all works out ok for you. If it doesn't perhaps this may be a good time for upgrades? I'm hoping to finally enjoy the car again after the top-end rebuild this week. Been without my car for >3 weeks now
Hope it all works out ok for you. If it doesn't perhaps this may be a good time for upgrades? I'm hoping to finally enjoy the car again after the top-end rebuild this week. Been without my car for >3 weeks now
08-15-2006, 12:43 PM
#7
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Jaime,
I basically agree with all here, and am a minor paranoic about my engines... (especially when parts cost so much like Porschy)
As much as I worry about a bent rod, the thought or whether it damaged(or will) damage the bearings and possibly the wrist pin (though I think rare, but trust kev and others here)
Running it for a while MAY cause more damage.... and IMHO you may not feel a minor bend in one rod.... though it may also make it idle or rev slightly off balance..
I know it's a nightmare, but you may want to pull it apart....... but I have also seen engines torn down with very slightly bent rods that ran well... and didn;t damage anything...
* any thoughts on looking at piston-deck heigth through the plug hole to try to see if there is a difference between piston heights/?? before a pull down?
I basically agree with all here, and am a minor paranoic about my engines... (especially when parts cost so much like Porschy)
As much as I worry about a bent rod, the thought or whether it damaged(or will) damage the bearings and possibly the wrist pin (though I think rare, but trust kev and others here)
Running it for a while MAY cause more damage.... and IMHO you may not feel a minor bend in one rod.... though it may also make it idle or rev slightly off balance..
I know it's a nightmare, but you may want to pull it apart....... but I have also seen engines torn down with very slightly bent rods that ran well... and didn;t damage anything...
* any thoughts on looking at piston-deck heigth through the plug hole to try to see if there is a difference between piston heights/?? before a pull down?
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08-15-2006, 01:19 PM
#8
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I don't think that you bent the rod if the engine went one REV.. However, it is the rod bearing that will take the initial hit.. You will hear a rod knock if the bearing starts to let loose. A bent rod will be tougher to hear..
08-15-2006, 01:37 PM
#10
Three Wheelin'
Thread Starter
Dang....count my blessings.....count my blessings..
Well, If I threw a rod bearing and hear a knock.....I"ll know. If the engine has a little uneven idle....I will not know cause of the cams already make the engine idle like a Harley.
What's the going around cost of tearing down the engine and replacing rods/bearings? What's been your total cost doing this??
Jaime
Well, If I threw a rod bearing and hear a knock.....I"ll know. If the engine has a little uneven idle....I will not know cause of the cams already make the engine idle like a Harley.
What's the going around cost of tearing down the engine and replacing rods/bearings? What's been your total cost doing this??
Jaime
08-16-2006, 12:15 AM
#11
Jaime...sorry to hear that. Why do such bad things happen to such nice guys! Hope its the least expensive and easiest of all possibilities to fix. Otherwise...time for a set of carillos, a 3.8 set up and maybe a stage 3 or 4 of Kevins....I think if its major that's what the Porsche gods are trying to say to you....good luck.
08-16-2006, 08:40 AM
#13
Holy crap Jaime. Splitting the case is 7-9K minimum. Reasonably it's more like 10K+. Mods beyond carillos add up quick. Rebuild time goes up as well (4 months and counting here). Sending good karma for your next firing up...
