6.9 no compression

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Feb 26, 2010 | 04:41 PM

#16

Cruickie

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No problem Padre.... I try to offer what I can when I can... what comes around goes around right?

As Starmilt was saying, Hydrolock (or hydraulic lock) is based on the principle that air in the cylinder compresses but a liquid does not compress. Therefore if you put to much liquid in the cylinder the piston will not be able to complete its travel to top dead centre (TDC). When this happens, something has got to give, either the liquid goes somewhere via some sorta freakin magic or the piston stops moving.....

Doing a wet compression check when compression is low is normal in a gas engine (much lower compression ratio) but even then you only put very little (less than a teaspoon's worth) to avoid hydraulic lock.
According to Starmilt (who's probably forgotten more about diesel engines than I even know!) this type of test is much riskier in a diesel due to the higher compression ratios.

Feb 26, 2010 | 05:09 PM

#17

Padre Pete

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From: Limburgerhof, Germany

Thank you Adam, I do appreciate the suggestions and adve that I receive from the good people on this forum. Although I have been working on diesel powered vehicles for the Army, there is so much more that I need to learn

So, hydrolock occurs when too much liquid is in the cylinder. Could too much fuel, say from a stuck injector, or water from a blown head gasket cause this?

When this happened, I had just put in new injectors and had driven the truck about twnety miles. Thats when the huge amount of white smoke and the very rough running occured.

Feb 26, 2010 | 05:23 PM

#18

johnboggs21

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From: Michigan

Quote:

Originally Posted by Padre Pete

So, hydrolock occurs when too much liquid is in the cylinder. Could too much fuel, say from a stuck injector, or water from a blown head gasket cause this?

yes too much fuel could hydrolock a motor

Feb 26, 2010 | 05:34 PM

#19

bill11012

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Joined: May 2009

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From: Texas

Quote:

Originally Posted by Padre Pete

So, hydrolock occurs when too much liquid is in the cylinder. Could too much fuel, say from a stuck injector, or water from a blown head gasket cause this?

Yes, theose two things are some of the more common causes.

Feb 26, 2010 | 05:46 PM

#20

starmilt

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From: Faibanks Ak.

Either one can cause it I had a bad injector hydraloc a big cam cummins one time.

Feb 26, 2010 | 05:47 PM

#21

Padre Pete

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From: Limburgerhof, Germany

If that one cylinder reived too much fuel, could that be cause of bd injection pump? Or that would ruin all of the pistons??

Feb 26, 2010 | 06:03 PM

#22

starmilt

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From: Faibanks Ak.

I doubt the ip would cause it if an injector caused it and it has 0 compression it would have knocked (sounded like a rod) from too much fuel or leaked off while it was parked and that uaually stops the starter for a second sounds kind of like a bad battery. either way it would have had to blow the head gasket on that cylinder bad for it to have 0 compression unless it was washing the cylinder down and scored the piston, if this is the case it should be smoking pretty good.

Feb 26, 2010 | 07:34 PM

#23

Padre Pete

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From: Limburgerhof, Germany

Okay so this is what I've learned:

1. Not a blown head gasket because no odor of coolant. Just white smoke from too much fuel.
2. Not injection pump
3.Possibly injector caused the over fueling and ruined valves

Now I have an idea of what to look for when I take it into a machine shop for work on it.

Thanks all for the information and sharing your knowledge with me. I think you have saved me a lot of money.