is water a no no?

[bulwnkl]

Actually, my math is correct.

 

Is it really? I'd really like to know the combustion chamber volume on various Subie engines. Simply taking the displacement/cylinder and dividing by the compression ratio doesn't give you the right answer because you're starting with displaced volume. Actual volume above (or beside in the case of our boxers! ) the piston is higher than that at BDC. Still, I'd really like to know CC volume if you have it?

 

Either way, a small amount of ingested water would vaporize under the pressure and heat in the cylinder. Once it does, it becomes compressible and there's still no issue.

[OB99W]

[...]Still, I'd really like to know CC volume if you have it?

This should work:

Clearance volume = cylinder displacement / (compression ratio - 1)

 

Either way, a small amount of ingested water would vaporize under the pressure and heat in the cylinder. Once it does, it becomes compressible and there's still no issue.

There's a flaw in your logic. Let's assume that the injested water somewhat exceeds the combustion chamber volume. I assume you'd concede that can't be compressed? Well, vaporizing the water just means you've spread its molecules out. Unless they escape the cylinder before compression, the compressive force recondenses them (or tries to), and you're right back to an incompressible state.

[The Dude]

Is it really? I'd really like to know the combustion chamber volume on various Subie engines. Simply taking the displacement/cylinder and dividing by the compression ratio doesn't give you the right answer because you're starting with displaced volume. Actual volume above (or beside in the case of our boxers! ) the piston is higher than that at BDC. Still, I'd really like to know CC volume if you have it?

 

Either way, a small amount of ingested water would vaporize under the pressure and heat in the cylinder. Once it does, it becomes compressible and there's still no issue.

 

 

Certainly, my calculations were close enough not only to be be in the ball park, but to be in the infield. The actual number critical to hydrolocking is combustion chamber volume (CCV). I was too generous in my previous post as the CCV of a 2.5L Subaru engine is 50cc. That's ONLY 1.69 fluid ounces, 13 cc less than my previous estimate.

BTW, liquids typically do not vaporize under pressure. Actually, it's quite the opposite.

So we know that more than 1.7 fluid ounces of water in even ONE cylinder will hydrolock the engine, possibly bending the con rods. I don't care what people do to their own cars. But suggesting that it takes "more water than most people think" to hydrolock a Suby engine strikes me as potentially poor advise. Unless, of course, most people think 0.25 fluid ounces of water will

hydrolock a Suby engine.

If a Subaru was meant to be used in deep water it would be called a boat instead of a car. Right there is a clue for you.

[1997reduxe]

To me, it only stands to reason that there are probably more sensors on 90s era cars than 80s. And that the engines' electronics are more sensitive. Also I would think that suddenly immersing the exhaust in cool water after it's been driven a while and is hot could cook parts there. (Not just sensors). this happened to our family station wagon once where we drove in snow for a looong time up near Erie and the inner jacket of the exhaust sealed almost completely somehow.

 

In my Suby experience, shortly after I bought my 97 Legacy (used, 140K, no check engine light) I took it to the car wash (while hot) and sprayed down the entire engine area to clean it. Immediate result: Check Engine errors. I drove it like that for a long time. Autozone said it was i think fuel level and oxygen sensor and possibly needed catalytic converter/exhaust or whatever.

 

Also, while living out at my sister's place when I first moved down here, when I didn't realize what the term "ex rice plantation" meant waterwise, after a previous nightong's intense rainstorm i came out to my car, which had been parked with the right side of it down over the edge of her raised driveway. I couldn't really see how deep the water was at first, but after starting it and backing up the length of the driveway i later realized it was inside the car and basically up into the glove compartment area. It died about two miles later, and needed a new computer. 650 dollars, and I was desperately hoping that would be all it needed. It was. Still runs good. I don't know about the 95, but the computer was right behind the floorboard behind a panel. now that's dumb! It should be on a tower 5 feet above the roof!

[Gloyale]

Also I would think that suddenly immersing the exhaust in cool water after it's been driven a while and is hot could cook parts there. (Not just sensors). this happened to our family station wagon once where we drove in snow for a looong time up near Erie and the inner jacket of the exhaust sealed almost completely somehow.

 

I took it to the car wash (while hot) and sprayed down the entire engine area to clean it. Immediate result: Check Engine errors. I drove it like that for a long time. Autozone said it was i think fuel level and oxygen sensor and possibly needed catalytic converter/exhaust or whatever.

 

 

Bad idea to pressure wash the engine. So is parking you're car in a flood plane. Then driving it before letting it dry out, duh..... Neither is really akin to a small stream crossing.

 

And the exhaust would be fine. That is like the very last of things that can be harmed by a stream crossing(unless there are hidden rocks,lol) I seriously doubt that you're cars exhaust somehow *warped* closed because of snow. Doesn't happen.

[triiifashions]

WOW

 

this thread got some response huh?!?

 

i thank all of you for your input

 

well its been raining here a lot and the creeks are up so no creek crossing right now

 

we will see how it goes when the water comes down

 

and after all the worst that can happen is a reason to crawl under that sexy subee with my wrench in my hand

 

lol

 

 

jeremie

[frag]

WOW

and after all the worst that can happen is a reason to crawl under that sexy subee with my wrench in my hand

lol

jeremie

 

...but just wait till it's out of the water

[triiifashions]

lol

[OB99W]

...but just wait till it's out of the water

Right, no Scooby SCUBA.