Purge rain water from a cylinder


2005, 2500
The following is a purely fictitious account of an injector seal renewal that is far too stupid to have actually happened: let's say (hypothetically) that a friend discovered a mountain of black death around cyl3 and that you agreed to help him get it fixed. Let's say that in your rush to get started, that you left your torque wrench at home about 30 mins away. After getting the offending injector out and cleaning both bores, you ball up some foil to stick in the bores and then close the hood before heading back home to retrieve your torque wrench. For the sake of the story let's say that about half-way home it starts raining and that a hole directly under the windshield which was hitherto unknown to your friend began to drip massive amounts of water onto the valve cover and injector gallery. Lets also say that the foil you wisely used to keep debris out was about as effective as toilet paper in keeping water out. So when you return with your wrench ready to finish the job you find the area that you just spent 2 hrs cleaning is now filled with water. So you grab a drinking straw to take a thief sample of how much water may have made it into the cylinder and discover that about an inch of standing water is resting on top of the piston. You are probably visibly frustrated at this point.
So not that you ever will, but If you ever need to purge a few pints of rain water from a cylinder without spraying fuel everywhere and purging the rail, you could (hypothetically) pull the fuel pump relay, reverse the orientation of the injector line and fasten the injector to it. The injector tip will be facing the battery at this point. Then crank the engine and spew a horrifying amount of liquid from the cylinder. You would do this until nothing but air is being forced from the injector bore. Then clean everything again and install the injector. You would then change oil and your friend's van will run like a snapped rat. Where was the plastic injector cover in this purely fictional not-real-at-all tale? Sitting on the drivers seat of course. Had it been doing it's job I wouldn't have been able to tell the story at all.


Well-known member
Reading this post I can tell you have never worked in a vehicle repair shop, big truck workshop, or fleet maintenance facilities.
Water/coolant on top of pistons is not an uncommon occurrence or condition in repair facilities.
Water and /or coolant finds its way into cylinders for sorts of reasons, indeed large amounts of oil on some engines will also find its way into flooding cylinders.
During on the job workshop training you learn how to deal with each specific occurrence and minimize the risk of engine damage.
Only a few weeks ago we were presented with a 1998 Jaguar XJR with a coolant flood and it full of water /coolant on #2 piston . Been there for weeks. Engine is dead. Out with the engine & off with its heads. Isolate the gasket problem and warped heads , cylinders being Alusil have no corrosion problems.
Car is a nice runner with some "healing hands " & green piasters invested , the "Chromed Pussy" growls again with renewed vigor!

At the same time, by some miracle of coincidence we got on a pallet from a SoCal junk yard the very same supercharged A/J Jag engine full of rainwater. Obviously stored outside customer had paid 900 bucks for it. Looking at off the truck, nine hundred bucks was seemingly too much !!

Still having pulled off the heads we discovered it had suffered a simple gasket problem due to overheat and some kind soul had the heads machined. This problems was crappy rebuild techniques. A YouTube grad at work, OMG!
Still clear out all the rainwater by a partial teardown, some new timing chains, gaskets etc and its a runner.
I gunned it up the I/70 a 100 mph after the car turned up .
Gotta love a well performing "Chromed Pussy".

Then there's the HUEI injectors, pulled by a DIY'r. Ford 7,3
each head has 2,5 qrts of engine oil in the gallery, now in the cylinders !
In the process of pulling injectors he yanked out a injector tube ,that dumped the coolant out of the heads into the pots , a right old mess.
Still, a pile of piasters and some proven techniques including cranking it over with no glow plugs in it, and it was a runner once again albeit a bit smoky like an insect fogger for while.

But as I have indicated a bit of prudence and "doing the knowledge" will get you out of a situation, and in my youth it was the workshop apprentice trap.
The hazing practice of apprentices by the old sweats was to aid wet cylinder liner removal in something like 12 litre diesel truck engine over a pit doing an "in frame"!
. Placing the 8" diameter cylinder liner dolly plate into the liner above the crankshaft, a big stepped 3ft punch was entered into the dolly hole. "Here lad hold at just yer like, as I hit it with a 14lb sledge" .
With swift upward swing the liner is punched out of the open block. The engine coolant jacket full of liquid readily prepared for unsuspecting snot nosed apprentices. As it flies out, the "dump" of 15 gallons of stinking coolant onto the unsuspecting youth! :devilish:
"Oh sorry Boyo, forgot to tell, you its gonna dump of coolant when I let fly"!.

Luckily for me I already knew of that trick so I stepped back as it was punched out so i just got my hands and boots wet !
Its all about techniques you see!
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2005, 2500
Great stuff Dennis, and you are correct! In my line of work "fleet maintenance" of vehicles is reserved for the guys who generally can't hack it at sea, so I haven't had the pleasure. I actually have a couple decades working on marine diesel engines. 12 of those years being at sea my good man. Respectfully, the engine room issues I've seen would likely make you soil your trousers. The point Sir, was that not that water entered the cylinder, the point was that it was avoidable had the protagonist in the tale just exercised a bit more caution, and that water, coolant , fuel, beer etc can be removed in the manner described. That's why it's in the 'write up' section after all Chum. You know, for the folks who have made good life decisions, and don't need to swing wrenches for a living to a have a little chuckle at my...er... I mean some made-up guy's expense.
But thank you for naming the engines that you've seen with fluid in the cylinders. Really shows the span of your experience, which I gather was your point.
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Well-known member
You have suddenly reminded me of an ex mechanic i employed for a short while, an honorably discharged US Navy engine room mechanic .
The ultimate haze
Apparently on a combined USN fleet journey mission from San Diesel to Hawaii, the crew compliment included some young Marine grunts.
Put to work during the voyage, their job was to clean the whole engine room area.
One job exercise was to polish a big brass button, but don't press it. FFS
One marine asked "what happens if I press it"!
The engine room ratings said "well go try it"!
So he did and shut down the boat in convoy in the Pacific. OH FFs the ultimate haze! :devilish:

The captain sent down the XO to investigate, after getting underway and rejoining the fleet /flotilla.
In short, fireworks since no-one would own up.
Talk about discipline below decks .

The matter was resolve when the XO said he would go easy on the Marine grunt.
Reminds me as a kid when I went inside an RN diesel sub---moored in our local dock on Navy Day
First stern words climbing down from the conning tower

Don't touch anything.!
Cheers Dennis


2005, 2500
Ha! Yes the ubiquitous "big shut down" story...I suppose every service has thier version of this tale. Im sure I've heard one bloviating time-suck or another try to pass this story off as thier own in my early years on the ships. Although, the securing of Main Engines by button-pushing is vastly preferred to the spectacular ways they can find to to secure themselves, at the worst possible moment. To quote Jethro Tull's Ian Anderson, "...your fingers may freeze, worse things happen at sea, there's good times to be had."

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