Hydrolock coolant leak?

[Tedybear]

I'm starting to think the Bronco II loves seeing me work on this during any summer/warm months. The other issues with the blown radiator, exhaust gasket blown out of the manifold (thanks for all that helped with that one btw)

Now I've got something oddly interesting. The truck has always had a lot of white smoke when I first start it up. Normal condensation is what I figured it was. Last few weeks? I've been driving the wife's VW beetle to work every other day to save the $$ (Her car gets 29mpg..the bronco gets about 17 lately)

Here's the rub: The white smoke gets pretty bad if I let the truck sit for more then a couple of days without running. I drove the truck on several trips on Sunday, and it was flawless--other then the white smoke when it started up. The smoke clears up after about 10 minutes or so.

Today I go and start the truck up, as I didn't drive it yesterday and wanted to maybe take it out later in the day. The engine turned over 1/2 a crank and came to a sudden "halt". Just as if the hand of God reached down and grabbed the crankshaft. I attempted a couple more times to start it, and it finally spun over normally and fired up. Engine vacuum is at times low when it first starts up and it's a tad rough with the idle for a few minutes until it settles down. (It's been that way for many months)

The white smoke reappeared soon after it started running and let up after about 5 minutes. No knocking (other then the usual noise for a 2.9) And it ran fine?

Here's what I think might be happening--and I would like some feedback to see what others think before I nose dive into more repairs and such.

I feel that the engine has a very small leak, maybe in the headgasket. When the engine hits running temp? The parts expand and the leak seals itself up. When the engine gets cold--The leak starts to slowly drain into a cylinder. In the case of this afternoon? The cylinder it normally drains into--Was at the compression stroke and the starter attempted to compress a liquid--bringing the engine to a dead stop. It probably finally cleared just enough space to allow the engine to spin over and it would have dumped the extra fluid out the exhaust--that would explain the white smoke, as it is getting burned off in the converter.

Our maintenance manager works on race cars and their engines and stated he thinks I'm right on what's going on.

My plan is this:

I drove the truck to the families house they are working on. My tools are all stored there. The truck drove flawless over to the house. I'm going to head back tomorrow and remove all the spark plugs. And if I do not see any coolant present? I will let it sit for several days with the plugs out. I'll then head back over on Sunday and disable the ignition and spin the engine over without plugs installed. I'm expecting to see a stream of water being ejected out of one of the cylinders when I do this. This should lead me to the side of the engine that has the fault.

As I said. I can drive this truck daily and there isn't any problems. A small amount of white smoke..very small..and it vanishes pretty quick. Give it a few days? I could use the truck to insect fog.

Can anyone suggest any other detailed testing I should do? I'm not going to bother with a block tester, as I can't afford the parts to do the tests. I figure if the coolant is entering the cylinder when cold? It should do so even more with the plugs removed. The engine has great compression (180lbs even) So I think the coolant isn't making it to the oil system. It's dumping just enough to be annoying.

And yes I've double checked the oil for fluid. Just has oil. No milkshake...Dipstick is on the full mark and has not been creeping higher. I think this is just a small leak that is only now starting to cause more issues--and maybe is getting larger so we can figure it out.

Ideas are welcome!

Thanks

S-

 

[ab_slack]

I would expect if coolant is getting into a cylinder that there is a good chance the plug for that cylinder will look different than the others.

I think you would do better letting it sit a few days with plugs in and then pull the plugs to take a look for coolant. If you let it sit with plugs out warm days may let coolant evaporate more than in confined space. And if not that, with the warm day/cool night cycle that could result in condensation forming around and in the cylinder (and the block as a whole) on humid days as block temperature will lag the air temperature change.

 

[Tedybear]

I would expect if coolant is getting into a cylinder that there is a good chance the plug for that cylinder will look different than the others.

I think you would do better letting it sit a few days with plugs in and then pull the plugs to take a look for coolant. If you let it sit with plugs out warm days may let coolant evaporate more than in confined space. And if not that, with the warm day/cool night cycle that could result in condensation forming around and in the cylinder (and the block as a whole) on humid days as block temperature will lag the air temperature change.

Oddly enough we just had the plugs out of the engine about a month ago trying to figure out the exhaust bit. I'll pull and double check the plugs tomorrow morning and see if any look 'steam cleaned'. The white smoke has been going on for a while now--but the plugs where looking all evenly worn and pretty much not any different then the others. But that was then--and this is now. Maybe something will surface.

As for humid days? We have several days of rain forecast. So you have a valid point. I'll pull the plugs tomorrow to inspect and spin the engine over to see if I get sprayed (yeah..that'll be fun) Then put them back in finger tight and recheck it a few days later.

Good thoughts, I'll see what happens.

S-

 

[RonD]

Yes your reasoning about compression stroke and the sudden stop of the crank makes sense.

You mention a small leak in the cooling system so I assume you have to refill system from time to time.

Just do a glove test while engine is cold.
Remove rad cap
remove overflow hose
Remove Coil wire, you want a no start
Spark plugs should be in

Put latex glove over rad cap opening, use rubber band to seal it, or use a balloon or even a condom , instead of glove.

Use a vacuum cap off the engine to block overflow outlet, or short hose with bolt in it

Crank engine
If you have a cylinder leaking into the cooling system then glove will bounce.
If it does then remove 1 spark plug at a time and crank engine.
When glove stops bouncing last spark plug removed was the leaking cylinder, re-install spark plug to confirm.



One other thing would be a cracked head issue, normally they crack between valve seats, but what if you got a crack at the valve seat, so compression loss is minimal and enough coolant leaking in for a hydrolock would be a 1 in 24 chance since a valve is only open 1 of it cylinders 4 strokes and a 6 cylinder engine has 24 unique strokes.
Some coolant would leak in and sit behind the valve to be burned off at next startup.

Could also be an intake gasket leak, coolant crosses over thru the intake at 2 corners, a leak into one of those 2 corner cylinders intake ports would produce your symptoms

Head gasket and cracked head issue normally do have the white steam at startup but also tend to pump up pressure in the cooling system causing overflow tank to .....well overflow, or they start to bubble.

 

[Tedybear]

Cracked head I would hope should not be the issue. Both heads had cracked when I purchased the truck years ago. I went with the world products branded replacements that supposedly had the upgraded design. Then again? All things are possible.

I'll give it a shot tomorrow with the basic pull the plugs out and crank the engine. If I see a spray come out of any of the cylinders? Pretty sure that will be the issue. (I'll just use the screwdriver on the solenoid trick. No fuel or spark. Just cranking goodness)

If that doesn't yield results I'll borrow some rubber gloves from work and some rubber bands. It's odd that most of these issues have worsened. I did bump the thermostat back to a 195(stock) one in place of the 180 I had installed. Trying to get the truck more efficient. Maybe the issue was there all along, but the slightly hotter temp is triggering problems?

I'll run through the basics. I will say this much. Head gasket job wasn't a fun one before. Costly as well. I might just park the truck up at the barn when I get the tools gathered up and start looking for a "parts" truck and swap in a 4.0 engine and harness/computer. I've checked out the how to list. It's within my skill level. If I can get a "rustbucket" with a good engine and drive train? It might be time to upgrade.

It just depends on what I find out is going on. Any major tear down will have to be put off for a while until I get the funds together. I'm tempted to just toss in some stop leak and nurse it along. (and I hate stop leak)

S-

 

[Tedybear]

Put latex glove over rad cap opening, use rubber band to seal it, or use a balloon or even a condom , instead of glove.

Would that be the "Love Glove" option?

 

[RonD]

Yes, the "Love Glove" works

There was a video of the "glove test" on youtube using a condom by a member here, but I think the poster pulled it

 

[Tedybear]

Yes, the "Love Glove" works

There was a video of the "glove test" on youtube using a condom by a member here, but I think the poster pulled it

I almost hate to ask what type would the truck enjoy best LOL. Ribbed...lambswool....

I'll be heading out to check on the truck in a little bit. I think if it is coolant in the cylinders? I'll probably toss in some silver seal and continue to drive it until I can afford to pick up a junker for an "Drive Train" transplant. I know it will be a lot of work to swap things over. But I like this truck to much to pawn it off on someone else-- Just have to give it careful consideration. I know the engine has issues that are slowly getting worse. (oil pressure starts at 60 in the morning and drops to about 8-10 after it warms up. Still quiet however) The truck is kinda telling me it's time to make a choice. Either find another 2.9 to drop into it? Drop several hundred back into it for a gasket set... Or find a junker with a 4.0 and make a bit of an upgrade that won't break the bank.

S-

 

[Tedybear]

Sadly all testing was really not conclusive. I pulled the plugs and did another inspection. One plug did have something 'odd'. The rest of the plugs had light gray/white looking color on the metal surround of the electrode. The odd one? Looked like it was colored with a matte black finish. Not really carbon build up...as that would (or should) look like black flack that you can scrape off with a finger nail. Just like someone took a magic marker and went to town.

I did crank the engine with the plugs removed. The same odd plug cylinder? Also had a very damp/wet look to the threads and seat for the spark plug. No clear "Gee that's really wet". Just looked a bit damp. The rest of the plug holes and seats? Looks like they where clean and "Cooked/Baked" clean (whiteish/grayish)

The glove test sadly didn't show anything clear. Granted I can put my hand over the radiator filler with the return hose plugged. I can feel pressure changes both negative and positive. (as in, I can feel my palm getting pushed against with pressure....and getting sucked down ever so slightly....)

I put a latex glove on it. And while it did inflate with coolant a bit while cold? Soon as the thermostat opened up? It started to suck the glove down like it's trying to draw in coolant from the overflow jug. By the time the thermostat opens up while actually driving the truck--The white smoke is gone and never comes back until it's stone cold.

I'm going to repeat all the tests again on Sunday morning. Just to give it several days to build up any fluid---and I'll use the old turkey baster to remove a good amount of coolant. Then try the glove bit. Seems to do the most 'action' when it's stone cold.

Thanks again for all the help!!

S-

 

[RonD]

Sadly all testing was really not conclusive. I pulled the plugs and did another inspection. One plug did have something 'odd'. The rest of the plugs had light gray/white looking color on the metal surround of the electrode. The odd one? Looked like it was colored with a matte black finish. Not really carbon build up...as that would (or should) look like black flack that you can scrape off with a finger nail. Just like someone took a magic marker and went to town.

I did crank the engine with the plugs removed. The same odd plug cylinder? Also had a very damp/wet look to the threads and seat for the spark plug. No clear "Gee that's really wet". Just looked a bit damp. The rest of the plug holes and seats? Looks like they where clean and "Cooked/Baked" clean (whiteish/grayish)

The glove test sadly didn't show anything clear. Granted I can put my hand over the radiator filler with the return hose plugged. I can feel pressure changes both negative and positive. (as in, I can feel my palm getting pushed against with pressure....and getting sucked down ever so slightly....)

I put a latex glove on it. And while it did inflate with coolant a bit while cold? Soon as the thermostat opened up? It started to suck the glove down like it's trying to draw in coolant from the overflow jug. By the time the thermostat opens up while actually driving the truck--The white smoke is gone and never comes back until it's stone cold.

I'm going to repeat all the tests again on Sunday morning. Just to give it several days to build up any fluid---and I'll use the old turkey baster to remove a good amount of coolant. Then try the glove bit. Seems to do the most 'action' when it's stone cold.

Thanks again for all the help!!

S-

A cold cooling system has no internal pressure, a water "pump" isn't really a pump it is a circulator so adds no pressure.
If rad is topped up all the way and rad cap is off then when started you "may" see a rise in the coolant level as circulation starts, but it would just be a rise then fall back to same level.

Engine running glove test is not as good as just cranking the engine for glove test, this is because the Compression stroke will force some of the 160+psi into cooling system to making glove bounce, and the intake stroke won't suck pressure from cooling system like it will with engine running and a vacuum is present on the intake side.

The fact the glove inflated at all would be a sign of the cylinder leak.

There should be no suction at rad cap at all unless coolant is shrinking from a hot expanded state.

Overflow system works with a 2 valve rad cap, as coolant heats up it expands, when enough pressure(14-16psi) is built up from this expansion the larger valve in the rad cap is forced open and the expanded hot coolant flows into the overflow tank until pressure is stable at 16psi, overflow tank is also called an expansion tank although expansion tank also covers other uses.
After engine is shut off, coolant will start to cool down, as it does it shrinks so the pressure in the system drops from 16psi, it will eventually cool down until pressure is 0psi, and then -1psi, this is when the small valve in rad cap is sucked(pushed) open and coolant starts to flow back into radiator from the overflow tank.
A bad small valve in rad cap would be seen as upper rad hose collapsing as pressure in the cooling system went into the negative numbers.

The pressures are all relative to 15psi air pressure at sea level, so 16psi in rad is 16psi ABOVE 15psi air pressure.
0psi means rad coolant and overflow tank coolant have equal pressure, 15psi.
When coolant in rad shrinks more then it gets to -1psi or 14psi relative, the 15psi pressure on the coolant in the overflow tank pushes itself into the 14psi rad to equalize the pressure.

If you have suction on the rad cap opening while engine is cold or only warm then it is leaking out or being sucked out and lowering the pressure in the cooling system, which would be the sign of a leaking cylinder.

A regular coolant leak from a hose, water pump, ect........will cause a -1psi(14psi) pressure because coolant is flowing out from the leak , so volume in cooling system goes down(shrinks) and small valve in cap allows the 15psi coolant in overflow to flow in.

 

[Tedybear]

Interesting. From the sounds of it the first cylinder front on the drivers side looks like it may have the issue. It's not much of a leak into the cylinder--as everything was damp, not 'wet' but damp looking. (The other 5 where dry as popcorn farts).

Main issue I had with the glove test was getting the stinkweed to seal on the radiator neck. Stupid China parts have a lot of sharp plastic edges and it kept tearing holes in the glove. Most likely it sounds like I should just plug the hole at overflow line and get a wider band. And just crank it (that was my fault, I figured running would be higher pressure and get a more dramatic result.)

I'll be pulling just the one plug on Sunday and repeating everything. If the truck kicks over and runs fine after all of the testing? I'll probably just continue to drive it as is--until I can afford to locate a donation truck/suv to swap the engine and related parts. (Or maybe just retire the Bronco in favor of a ranger in better mechanical condition.)

Really tough choices.

Again, my thanks for the help. (still wondering why I never get any email about replies. It's hit or miss with my stopping in here checking)

S-

 

[Tedybear]

Well that was a whole lotta nothin...


Had to repair the families lawn mowers yesterday due to going to the local pick 'n pull for VW parts today. So I decided to check out the bronco again and try a couple of other things.

"Rented" a cooling system pressure tester for an hour. Just a FYI: Never rent the "Advance Auto" tester made by AllTrade. (stupid thing said "Pro" on the huge black container...worst one ever.....) They do not even have a compatible radiator cap adapter. Have to attempt to use one of the 3 tapered rubber wedgie pieces crap.

So first thing we did was remove the one spark plug that looked suspect. Completely bone dry. If it was leaking into the intake and sitting above the valve? We then spun the engine over. Nadda. No fluid at all. Normally after sitting a few days this thing blows major white smoke. But dry as a bone.

So I pull the rest of the plugs and repeat the same test---and use a pressure tester on the system. Wife had to hold the stupid adapter to the radiator so it wouldn't pop off. (Did I mention that is a POS design?)

Pressure stayed put for about 10 minutes (never dropped off until the stupid adapter popped out)....continued to let it sit and then spin it over. Still dry...The theory that this leak only happens when the engine is stone cold, something opens up enough to allow the leak--and then self seals after it gets to temp?

We put it all together again, started the truck up. Small amount of white smoke--drove it to the families house 15 miles away and back. Flawless.

At this time I figure we'll just continue the basic maintenance and drive it like usual. Until something gives out completely? This seems to be one of the most elusive buggers I've ever dealt with. I'm going to have to wait until the engine "HydroLocks" again while trying to start---and then pull the plugs and see what gives.

S-

 

[Andy D]

I was feeding my 300k mile 528 some water through a vacuum line and it stalled. I tried to re-start and it wouldn't turn. It was a long 5 minutes while I spun the plugs out, and tried again. Water did trickle out of #6 , just a teaspoon. I put the plugs back in and drove it another 50K miles. Wheew!

Are you sure it isn't just condensation ? E10 gas exhaust makes a sweet smelling vapor and water trickles out of the exhaust every time I start the Rat.

 

[Tedybear]

Sadly this is the only truck/car/thing on wheels that blows a ton of white smoke when I first start it up after a couple of days of not driving it. Took it down the street a couple of weeks ago when I first tried to track this down--and it looked like I was trailing a white cloud behind me...Parked the truck and let it sit for about 15 minutes and no more white smoke the rest of the day. I figured it was in the converter and it had to burn itself out/off.

Just trying to track down the source of the engine locking up. Today was interesting...Blew a little white smoke, and we drove it to Syracuse to a pick/pull yard for VW parts-- (damn flippers got to the cars first and got some of what we needed) Truck did fine all the way down and back.

Just going to have to live with it until it does something that can be tracked down.

S-