Backing up boat trailer - tailpipe underwater

Err, perhaps you are backing your vehicle too far into the water...just a guess.

You did not state is the exhaust was stock or not but I have a theory here as to what likely may have happened. When your engine idles there is actaully a negative pulse several times a second in the exhaust system due to low flow and a combination of sonic wave travel and the rapid cooling of the exhaust gas. When you placed tailpipe in the water it started to ingest a little water during the negative pulses and it worked its way up into the system further which further cooled the pipes and gas and increased the draw of water into system and it may have gotten into engine itself. If you have a dual exhaust it would actual tend to be more prone to this yet because the quicker expansion and cooling of gas at a idle and stronger negative pressure pulses. Expensive lesson for sure. If you want to avoid this in future, keep tail pipes out of water and place a restrictor in pipe(s) durring this time so the a higher pressure is maintained during idle cycle which reduce the negative pulse to zero. If you have duals, go back to a stock exhaust.

----------------- TheSnoMan.com

I have a theory too.

My theory is that before you give anymore bs answer's you should revisit all the other threads in which you have posted incorrect info, answer's and advice. You probably should start with the V10 thread., then move to the transmission bolts thread. I'm sure even you can grasp the theory.

Roy

I have another theory and it is that you are full of s#!t Roy but knock yourself out if it makes you feel good. People like you need help and help that you need you will not find need here. Anything that you do not understand you start your BS and show your total real lack of understanding. You must be a very insecure person. (it shows)

----------------- TheSnoMan.com

Hole, who has been posting wrong and misleading info? You!

Hole, people like you should have their keyboard taken away.

Hole, if I don't understand I ask questions. I don't post wrong answer's to request's for info. If I don't have the answer I don't say anything, you on the other hand can't seem to help yourself and post wrong info.

Hole, your lack of understanding was shown in the V10 thread when you posted wrong info. Again in the transmission thread your info was wrong and if applied could have resulted in damage.

I'm insecure? Nope, I just have a thing with people who spout off bullshit answer's that are totally wrong. Again I invite you to return to those threads that you posted wrong info in and answer the questions that followed your posts. That should be pretty simple. Now we will see by your actions who is really insecure.

Oh, just for your head, this situation will NOT go away until YOU take corrective action.

I don't know about hemi's but my cummins exhaust has never given me a problem when sunk in water or mud.

Well, I seriously doubt the repair was caused by water intrusion. I myself have had my vehicle in water at ramps and once even through 3 to 3 1/2 feet of water for 1/4 and no damage at all. Granted I was nervous as hell but my Ram made it all the way. This is a 2001 2500 4x4, no lift kit...standard height.

That was 1/4 mile distance.

I'm gonna hate myself for this......

And as usual your theory is a tad bit far-fetched..

When your engine idles there

I'm sure you read this in a book somewhere and picked up on the theory of it but didn't finish reading the chapter.

When you placed tailpipe in the

I'd pay good money for you to demonstrate this in the real world. I'd even let you use my own personal truck. I'd even drive down to Dayton (close enough) for you to do it. Maybe, just maybe if the engine in this demonstration had enough non-sealing exhaust valves, no muffler or cat converter it might do this but I really doubt it. Think of this, an engine is an air pump. If the engine is to stay running, it must be moving air. While a little water may get inside the tailpipe, do you really think that water will take on the charactoristics of a salmon and swim it's way thru a muffler, ten feet of pipe and a cat converter while battling that flow of air coming thru the pipe?? I think you're confused this issue with the issue of an exhaust manifold gasket leaking that can suck in cold air and burn a valve.

If you have a dual exhaust it

A restrictor in the pipe????? Muffler or cat converter fit this description???

I think I'd rather try to reason with my three year old grandcritter..

Denny

Why?

Not at all. It is very logical and bases on the physics of expanding and cooling gasses.

You should do the reading because it you applied a vacum gage to the exhaust system at a idle you would find that a negative plus does exist at a idle at time and it would be worse with duals.

The water would not have to "swim" up the pipe as it would be drwan up it by the negative plus durring low flow at a idle and it would be self feeding in that as the water got in there it would cool the gases more and increase the strength of the negative pulses. ALso you must factor the angle of the ramp because if it is a shallow angle it would be easier for the water to be drawn up into it. People tend to think that there is always psotive pressure in the exhaust system but this is not always the case at a idle with a low restriction system. Hold a piece of paper over exhaust outlet at a hot idle and watch how it is drwan tight against it several times a second and the lowe the restriction of the exhaust, the more noticable it is at times. A diesel would not have this problem because it moves a lot of air through system all the time because there is no throttle valve limiting the intake air flow.

No a cat would not fit this bill you would need to have a more restrictive exhaust so that a negative pressure never developes and this could be done temporarily with a retrictor inserted into pipe(s) outlet when it water.

Only if you are on that level too and if it makes you more comfortable. I do not make the rules of physics but I know how to apply them which some do not so they dismiss it as hogwash. I have yet to see another possible plausable theory that could explain this posted here. Do not shoot the messanger because you do not understand the message. There is a LOT more to the dynamics involved here than people realize.

----------------- TheSnoMan.com

dood, the only expanding and cooling gasses you got is in your pants.

what?

That's exactly what my line of thought was as well. Low oil, running, backed down on an incline with oil away from the pickup in the pan more than likely...left the vehicle so didn't hear it clammering for oil and 'walah' (sp)...toasted lifters and possibly more that can only be seen by a complete teardown.

Hey Hole!! Never mind the BS here. Go back up a couple of post's and answer the questions!!!

Oh, I've adjusted your sig so that is more reflective of your BS. I think it is much more fitting don't you?

Or Budd.

beekeep

ahhhhh, that may be taking it a bit far greg.

As usual it appears you pulled this * theory * out of your ass. Where do you get all these bullshit *theories* from ? I can tell you for a FACT you are full of shit, as usual. I have owned four wheel drive trucks for the past 30 years and use them off road quite often. I have owned 4, 6 and 8 cylinder trucks with stock exhaust, dual exhaust, headers, with converters and without converters. I have had them idling in deep water and shallow water at any angle you can imagine. I have even shut them off while in the water. NOT ONCE have I had a problem with water entering the engine through the exhaust. I have been on organized four wheel drive runs where there were dozens of other vehicles in the group. NOT ONCE did anyone have a problem with water entering an engine through the exhaust. I have to call bullshit on your *theory*.

Now the OP stated that he needed his lifters replaced. Now I would like you to explain how water got into his lifters through the exhaust without doing any other damage to his engine ? I can't wait to hear this *theory*.

And while you are explaining things I would also like to know where the knock sensor is on a V-10 engine in a dodge pick up.

The said part is you are wrong but since you do not understand the dynamics involved, your figure it is BS

You are missing the point here. It is a cycle that purculates the water up the exhaiut system. The flow of hot gasses at a idle is very very low. because of to reasons, one is that most of the energy is caputred in the engine via expansion in the cylinder and the rest of most of the heat is lost to engine block and exhaust so the air flow is very low. The net positive air flow is about 15 to 20 CFM at atmospheric pressure or about 10 CFM per pipe with duals. The peak pulse velocity is about 7 FPS (little more than a light breeze) when pulse is first started but after pulse a negative wave it created is back pressure is low. (this is because the average pressure is so low that it allows a negative cycle to form) THis creates a vacum that sucks water up and the negative pulse is longer in duration so it travels up pipe and is not expeled unless volume of gas in pipe is increase to a point that the average pressure is high enough that when the negative impluse cycle starts that it does not go negative enough to offset the postive pressure in pipe in relation to atmospheric pressure. Simple physics here but too simple for some.

A inboard runabout has a exhaust system baffled and designed to be under water duh.... a car does not.

You should take time to read more and learn before you shoot down something you do not understand. You know I worked on the GPS system proto types almost 30 years ago when government tested it under the MilStar projet name. I can tell you EXACTLY how it works and why because the theory of operation has not changed to this day on it though the packaging has. (youcan kinda thank me if you use one today in any form becuase myself with others worked the bugs out if it back then) There are three types of people in newsgroups, those that want to share knowledge, (myself) those that do not know and want to attack others or cause trouble on things they do not understand for a notch on their holster (you) and those wanting to find the real reasons way. People such as yourself tends to hurt those that are asking for a solution or cause to begin with and if you do not understand the subject completely, do not comment on it.

----------------- TheSnoMan.com

Nah. beekeep should quit his day job. I've gotten more laughs the past week from this ng than any comedian that comes to town ...

Craig C.