[Anonymoose]

Apologies that this is a bit long, I don't want to leave out something that might be directly relevant...

94 Ford Taurus GL 3.0L 144K miles – on short errand, car suddenly began making a rattling/knocking sound whenever I was on the gas, but either stopped or was quiet enough that I couldn’t hear it when off the gas and just coasting. The noise was almost as if the car was a diesel rather than gas… that’s the best I know how to describe it. I was only a mile or so from home and decided to try to make it home. No engine warning lights were on, temp was totally normal too (mid range on gauge). Got to a spot where I had to stop briefly before turning, and engine almost died but gave it gas and it kept running. Got a block further, and then the engine just cut out.

I let it sit over night. Checked the oil on the dipstick and it looked normal (no metal flakes/chips in it, or anything else). Started car just fine, and it sounded NORMAL, not the knocking/rattling/diesel sound. Drove it the block home.

Once home, discovered I’d had huge coolant loss – added over 2 gallons of water (engine supposedly takes 11 qts). I assume engine overheated causing the noise and then the engine dying – but do NOT understand why I never got any warning lights and the temperature gauge read normal?

Anyone know how that could happen or have thoughts on that?

Anyhow – the water pump was leaking from the weep hole, so I replaced it. STILL had large coolant leak. Let a shop next door find the leak and they pressure tested to find it (unnecessary, leaked as soon as engine was on and for a few minutes after off). Anyhow, discovered that it was from the ‘heater tube assembly’ that feeds the heater core. Heater core had gone bad several years ago and I’d just bypassed it because replacement would take removing entire dash & supposedly evacuating AC also… So I jury rigged hoses to go from the water pump bypass hose and bypass the entire set of tubing.

Whereupon I discovered that they overpressurized or radiator was about to go anyhow, because now I had a leaky radiator when I didn't before. Replaced the radiator. Ran car just a couple of minutes to check for leaks, no leaks. WHEW. Drained out a little water, and put in some of the prestone coolant cleaner – its the stuff that you run with for 3 to 6 hours and it cleans out corrosion from the system & block.

Then ran car for about 20 min with hood up, just still checking for any leaks and letting the cleaner get started… at first was surprised that it only got to mid-range temp wise when the thermostat tripped and for a few min it ran between less than mid-range temp to spang on mid-range, then it seemed to shift and go a bit warmer, from mid-range up to a little higher but still nowhere near the top of the gauge or the red line area. Noticed, however, that there was some a little bit of smoke/steam coming from the engine compartment.

Then also noticed that the fluid in the radiator overflow container was bubbling/boiling – but have no idea if that was just normal filling as the engine heated up, or ??? It wasn't overflowing, but was bubbling/boiling (I've never looked into the overflow container when a vehicle was running at op. temps, so no idea what's normal or not).

Then suddenly got a NEW leak UNDER the car, a watery oil… from the passenger side of the vehicle sort of in line with the middle of the wheel.

Turned the car off. During all of this the car sounded fine. When it had cooled just a little, pulled the oil dipstick and now the oil looks a little like coffee with a little creme in it, sort of opaque dirty tan color… its not foamy looking like an emulsion however, but I’m assuming this means I’ve got water in the oil? That the engine started running a little hotter once exhaust gasses and/or oil got mixed into the water/coolant system?

Could the original episode have done serious damage, but somehow that didn’t appear until either the engine was at operating temps again and/or I had the coolant system fixed so it was pressurizing properly?

Do these symptoms peg the problem - and if so, what does it mean? Or are there multiple possibilities? Suggestions for how I can tell what the problem is or at least narrow it down?

If it is gasket/head/block problem, what are experiences with some of the liquid additives that claim to be able to seal these sorts of problems like K&W Engine Block Sealer, Barr's (they've got several options I guess), Steel Seal, Thermagasket, ThermalWeld, etc? Do any of them work, and if so, is any one of them better than the others?

[Cuda_jim]

Sorry to say you have at least a head gasket problem...if you run it long enough and it got hot enough you may crack a head or the block. The only way to know for sure is to remove the heads. Let us know what you find.

[Anonymoose]

Hi Jim,

Between low back surgery a few weeks ago, and resulting horribly tight finances, and this being my only vehicle, I'm in trouble with this one. I about killed myself just doing the water pump then hose bypasses, then radiator replacement - but didn't have any option because of the costs if I'd had a mechanic do the work (was quoted $350 to $450 for water pump, $125+ for heater tube assembly part alone, didn't bother to get full quote on that one, & blew my mind, $550 for radiator replacement, $100 for rad, the rest labor!!!)

If the darned vehicle was overheating from major coolant loss, why in the world didn't the temp gauge reflect it? It seems to be working still... or at least reflecting temp changes, I've no way to know how accurately...

Would a mechanic be able to narrow the problem down more without it costing a fortune, or is it impossible to know more than that at the very least its a head gasket?

Do any of the head gasket/block sealers work in some cases like this?

[Anonymoose]

For whatever my experience with this stuff might be worth to others - I wound up using a head gasket/block sealer called Blue Devil. I gather its just pure "liquid glass" or "water glass." Wikipedia has a fascinating article on the stuff - its been around for ever, and its incredible the number of widely diverse applications its used for. Like in the 1920's, to preserve eggs for up to 9 months!!! Pressure treated lumber, concrete/stucco waterproofer, etc etc., even a little scary, but the "cash for clunkers" required dealers to drain all engine oil, insert 2 quarts of liquid water in the crankcase, run engine - and presto, within 30 seconds to just a few minutes, engines irreparably seize. You can even buy liquid glass from some pharmacies! I have no idea if there are different concentrations that might make buying one of the auto product liquid glass's any better than what you'd get from a pharmacy or not, however.

For head gasket/block/intake manifold seal/leaking freeze plug sealing, the older versions of liquid glass aren't compatible with antifreeze, and you've got to have ALL of it out and well flushed, or you can gunk up your entire coolant system. I have NO idea how, but the newer versions apparently are compatible with antifreeze. I'd be VERY interested in hearing from anyone who knows how they make it compatible!) The 'blue devil' brand seems to be somewhere inbetween. They have you flush all antifreeze out before using the product, but say after it's sealed its fine to leave the Blue Devil (BD) in the system and just drain enough out to re-install your thermostat and add appropriate amount of antifreeze.

Anyhow, I flushed system thoroughly, removed thermostat per instructions, added pure water minus easily enough space for the BD... then you start your car and immediately while cold you slowly (over 30 seconds or more) pour the BD into your radiator. For systems under 3 gal (mine's 11 qt), you only add half the bottle. Then you let the car idle for 50 minutes or longer. I wish they sold it in half sizes!

Right at about 40 to 45 min, the oily water leak under the car that only started when car was at operating temps and dripped onto part of exhaust or something hot enough to make it steam/smoke in the engine compartment very suddenly completely stopped dripping/leaking. I let the vehicle run for about 70 to 80 min before shutting it off, keeping a close eye on temp gauge throughout. Even tho it was about 108 outside (SW desert), car once at temp was roughly 2/3rds of the way up the 'normal' temp. range of the gauge. It really seemed that right about when that external leak sealed, temp dropped to more like 1/3rd of the way up the range to maybe mid-range. Stayed there.

A little while later I took the vehicle to have oil changed. Car never got above about 1/3rd up the gauge, e.g., very bottom/cold end of "normal." Then I went on a short errand, maybe 3 to 6 mi roundtrip. Checked oil, clean as a whistle, no signs of water in it.

The following day I took it on the interstate for a round trip of approx 20 to 25 mi, speeds mainly 65 to 75. Recall, no thermostat, and only water & the BD sealer for coolant. Ambient temps again about 106 or so. First half of trip car still ran bottom end of normal range. On this gauge, there's the blue "cold" line/block, then a big gap, then the word "normal" across the gauge, another big gap, then the redline/block for overheating. Between the "r" and the "m" is 12 oclock, dead on mid range normal. On exiting the freeway, temp very briefly got to the "m" or between the "m" and the "a" as I lost the speed of air cooling but before I even turned to go across the interstate overpass, it dropped to dead on mid-range. Then the last half, mostly at 75 mph, and it stayed mid-range again until it briefly went up as before on exiting the freeway. Checked the oil as soon as I got home, still clean as a whistle, no signs of water. YIPEE!!!!! Still very nervous about it, but looking good knock on wood!

The next day (monday) I had an appointment on the far side of town. Still no thermostat, just water & BD sealer in it. Trip that should have taken approx 30 min took more like an hour, with a good bit of the last part stop and go on road with construction - sitting thru 2 cycles of every blasted light. Car seemed just fine, including temperature. Took different route home, all expressway, but kept it to about 60 to 65 mph, as most of that was also a bit of a grade upwards and didn't want to risk overheating. Even so the hottest it got was on the "a." On arriving home, checked oil - still clean as a whistle. Coolant (ok, water & BD) level hadn't changed at all either.

God knows how long the seal will hold. Wiki (which is notoriously inaccurate on some articles), says it CAN last up to two years or even longer. Doesn't say it WILL, says it can tho. Apparently wherever it forms a seal, its very strong and won't melt again either - high enough heat (I think it said approx 220 degrees) causes water to be driven out of the water glass, which then plates out into the leaking spot in subsequent layers until the hole is sealed. Takes temps over 1500 degrees for it to melt again - ain't happening in a car/truck engine! The stuff although very strong is also fairly brittle... so my guess would be that age and the constant vibration of an operating car can eventually cause the seal to fail. At which point, what the heck, why not just use a sealer again? Key I think would be to keep a close eye on coolant temps, oil condition, fluid levels, any signs of external leaks or degraded engine performance, etc., so you notice a recurrence very shortly after it occurs and reseal before any damage is done. Then change out any contaminated fluids of course.

So now I'm trying to decide how long to drive with sealer in before replacing thermostat & adding antifreeze... and whether to drain all of the sealer out before adding antifreeze (help ensure no untoward chemical reactions between the sealer & antifreeze, although they say its perfectly safe/compatible), or just drain out enough to be able to put new thermostat & antifreeze in (e.g., leave in some sealer, on the idea that it may then seal up any new small leaks that try to form).

Some sealers have not only the liquid glass, but also metal ions or even visible metal in the mix - others have the liquid glass and other types of fibers... the idea there, I suppose, is that the metal and/or fibers bond into whatever hole/leak you have and may form a stronger longer lasting seal than the brittle liquid glass alone.... downside is an increased risk, maybe, of the sealers with fibers/metal, clogging small oil ports/channels or coolant ports/channels that you do NOT want clogged/sealed.... I have NO idea which version(s) actually result in the most durable or best seal.

So, that's the scoop on what I wound up encountering. I'd be VERY interested in more or better information from others about the different types, any solid technical info on which types actually make the best/most durable seals while being pretty safe to use (e.g., no damage to vehicle likely to occur). How they make some anti-freeze compatible while others aren't, if there are different concentrations available, and so on. Or even just hearing other folks experiences with the various block sealers, including what their vehicle symptoms were that led to using a sealer, which sealer brand/type was used, and what the results were - including how long the seal lasted if a successful seal was obtained.

[Canuck623]

Don't leave the Tstat out for long. That will cause an overheat as well. When you remove the stat you alter the size of hole the coolant goes through. The coolant then rushes past the cylinders etc so fast you don't get a proper exchange. This over heats specific spots in the engine but will never show on the gauge because the coolant isn't picking up the heat to transfer it to the air via the radiator. So get a stat in there fast. I would go with a 160 or so just to be safe but get that orifice down to slow the coolant.

[Cuda_jim]

Totally agree with Canuck623 ^^^ You need to rinse it out, install a new thermostat and coolant too.

BTW: I've used a product very similar to Blue Devil, it may even be the same stuff. It's called, click me--->Moroso Block Sealer (with ceramic). It comes in 2 flavors, Red and Blue. One is installed with plain water, the other is installed with antifreeze...the plain water version is the best. Hot Rodders have been using it in high performance engines for decades......including me
I installed it in a regular car that had coolant pouring from the exhaust pipe. It sealed it up..... 5-6 years ago and is still being used today to deliver mail. Quite the testament, huh?
Just be sure to follow the instructions to a "T" (it seems like you did). The Moroso product can be installed a second or third time....followed with a plain water rinse, new thermostat and coolant. Hope you have the same results.

[jonmark1985]

Originally Posted by Canuck623

Don't leave the Tstat out for long. That will cause an overheat as well. When you remove the stat you alter the size of hole the coolant goes through. The coolant then rushes past the cylinders etc so fast you don't get a proper exchange. This over heats specific spots in the engine but will never show on the gauge because the coolant isn't picking up the heat to transfer it to the air via the radiator. So get a stat in there fast. I would go with a 160 or so just to be safe but get that orifice down to slow the coolant.

You can peal the guts out of the thermostat and use just the housing as a restriction as well.

[Poppy]

Anonymoose,
Thanks for writing back and sharing your experience. Hopefully it will continue to work for you, and others will benefit from your willingness to share your experience. Please give us a 6 and 12 month update.

['80monty]

the only stuff like that i've ever used was the radiator stop leak (i forget what brand). my fairmont had a small leak in the radiator so i decided to try that for a temporary fix. that was over a year ago and its still holding.

[Anonymoose]

Originally Posted by Canuck623

Don't leave the Tstat out for long. That will cause an overheat as well. When you remove the stat you alter the size of hole the coolant goes through. The coolant then rushes past the cylinders etc so fast you don't get a proper exchange. This over heats specific spots in the engine but will never show on the gauge because the coolant isn't picking up the heat to transfer it to the air via the radiator. So get a stat in there fast. I would go with a 160 or so just to be safe but get that orifice down to slow the coolant.

Thank you for this info and warning! I had no idea it could read cool, but have hot spots this way. I'm having a little trouble conceptualizing tho - Lets go to the "correct" engine with thermostat in to be sure I'm understanding the system properly. I had thought that when the thermostat was closed there was still a set flow (speed and volume) of coolant throughout the engine. Then, when that coolant hit x temperature, your thermostat opens and allows radiator water to enter the circulation........Oh, I think I get it now. You're saying that because the thermostat is in there, it physically allows significantly less volume thru at any given time, thereby the speed of coolant flow thru the engine is less than if its just the housing, no thermostat. Sort of like the difference of shooting a garden hose into a pipe system vs a fire hose, right? The 'fire hose' (no thermostat in place) would then force a greater flow speed than a garden hose.... am I understanding this correctly?

On the t'stat... I think the specs are for a 180. Any reason or benefit for me to go with a 160 as you mention instead? If the sealer has worked right and I've got antifreeze in, I shouldn't have an overheat problem - and wouldn't it starting to run a little hotter than normal be a clue for me that I might need to run sealant again?

[Anonymoose]

Originally Posted by jonmark1985

You can peal the guts out of the thermostat and use just the housing as a restriction as well.

Jonmark, you're meaning using a thermostat in place in the housing, just with the center spring mechanism torn out? Or are you meaning just the actual housing that the t'stat normally sits in?

An offside - when I initially pulled the housing (BEFORE running the sealer), the old thermostat was effectively welded in the housing!! Not literally, but I could NOT get the blasted thing out! Took pliers to it, and no way I could get it to turn counterclockwise the slightest iota. Finally walked across the street to the auto parts store, thinking maybe I was an idiot and doing something wrong and afraid of really messing the housing up or something that way. They were floored too. A couple of them did mention that it wasn't uncommon for old thermostats to stick in the housing, but hadn't run across one this difficult. Another customer said he'd seen one so bad, they gave up and just replaced the housing! Anyhow, with application of some WD40 (they didn't have one of the better penetrants handy/open), and a really big pair of channel locks, and some muscle, they finally managed to get the buggar out for me.

Now I'm just praying that when I go to put the new t'stat in, I don't find the housing welded to the engine by the block sealer... I know it SHOULDN'T have, because the temps shouldn't have gotten high enough to activate it there - but then I've also heard that if you run with radiator cap loose for too long you can find it sealed to the radiator, as if its air contact that activates the stuff.... and the stuff does supposedly seal any leaks in the radiator or heater core, which implies air activation. In other words, I don't know and it makes me nervous! But VERY grateful that it seems to have sealed off the coolant leak into crankcase oil and the external watery oil leak - e.g., $60 magic in a bottle vs. ruined engine and junked car. I'll take the $60 cost and a small case of the nerves, thank you. :-D

[Anonymoose]

Originally Posted by Poppy

Anonymoose, Thanks for writing back and sharing your experience. Hopefully it will continue to work for you, and others will benefit from your willingness to share your experience. Please give us a 6 and 12 month update.

You're welcome! I'll try to remember to post back periodically that way. Oh, when I was trying to decide which block sealer to buy, another customer saw what I was looking at or heard me talking with the autoparts employee about them. He walked up and pointed to the Blue Devil stuff and said he'd used it for a major/rebuild engine type problem in his car, worked like a charm and was still working 8 months later - when his tranny died and he got rid of the car.

God I wish there were some independent research organization (like consumer reports used to be, but I don't trust their independence anymore) that had actually tested all of these different sealers to see how well they both initially work AND how long a seal tends to last under operating conditions. There IS a standard for testing sealers,

ASTM D3147 LABORATORY TEST

but I was only able to find results for a couple of the sealers, bars versions in particular. For example, if you go to Bar's Leaks Head Gasket Fix then click on the little link below the product for "tech sheet" (small pdf) then scroll to the second page and you can see the results. I don't know what the "fluid lost" bit means - maybe how much fluid passes thru the hole before it seals? Plus, of course, there's no data on how long a seal lasts.

They all CLAIM a seal is permanent.

Even so, if anyone else can find ASTM testing data on other sealers, I'd be VERY interested in seeing that data!!!

[Canuck623]

Originally Posted by Anonymoose

Thank you for this info and warning! I had no idea it could read cool, but have hot spots this way. I'm having a little trouble conceptualizing tho - Lets go to the "correct" engine with thermostat in to be sure I'm understanding the system properly. I had thought that when the thermostat was closed there was still a set flow (speed and volume) of coolant throughout the engine. Then, when that coolant hit x temperature, your thermostat opens and allows radiator water to enter the circulation........Oh, I think I get it now. You're saying that because the thermostat is in there, it physically allows significantly less volume thru at any given time, thereby the speed of coolant flow thru the engine is less than if its just the housing, no thermostat. Sort of like the difference of shooting a garden hose into a pipe system vs a fire hose, right? The 'fire hose' (no thermostat in place) would then force a greater flow speed than a garden hose.... am I understanding this correctly? On the t'stat... I think the specs are for a 180. Any reason or benefit for me to go with a 160 as you mention instead? If the sealer has worked right and I've got antifreeze in, I shouldn't have an overheat problem - and wouldn't it starting to run a little hotter than normal be a clue for me that I might need to run sealant again?

You have the concept 100% correct. Ford's OEM thermostat would have been a 192* version. My thoughts behind a 160 were just giving a cushion between the opening of the stat and the max temp you want to see.

[Anonymoose]

Originally Posted by Canuck623

You have the concept 100% correct. Ford's OEM thermostat would have been a 192* version. My thoughts behind a 160 were just giving a cushion between the opening of the stat and the max temp you want to see.

Thanks Canuck. I wonder if the lower flow also helps reduce any temperature shock to the metal from the radiator coolant v. coolant in engine at operating temps...

Regardless the hot spot issue of no t'stat can't be good for an already iffy/bad head gasket/head/block I wouldn't think, not to mention everything else in there.

Any opinion on whether I ought to leave some of the sealant in the system when I add antifreeze to potentially seal any other leaks that might be starting, or if it'd be safer to drain it all out and just go with proper coolant mix?

[Anonymoose]

Canuck, now you've got me wanting to see the thermodynamics of heat transfer with fluid flow at the various coolant transfer times (e.g. w/ vs w/o thermostat in) to see just how much the transit speed really does or doesn't affect engine spot temperatures! (its the scientist in me). Intriguing regardless - and heck, practically speaking if its possible that hot spots could be created running without thermostat, well, it'd be silly to not be sure to have a thermostat in, since having one out could conceivably cause problems but once the sealer has been run, there's no harm the other direction (e.g., having t'stat in as it should be).

[Canuck623]

Not sure on the sealant question. Have never used it. I understand one type is ok with antifreeze while one is not. Would depend on which one you used. As for thermodynamics.....you got me there.

[Ratpackr]

The reason you didn't get a 'HIGH' engine temp reading is because-- The temp. sending unit is designed to sense 'water/coolant' temps .. if the sending unit was dry (ie: no water/Coolant) the reading was false...

I used to put an aftermarket gauge on vehicles & put the sending unit @ one of the 'block drain' port. They are at the bottom of the block where water/coolant usually constant..

[Anonymoose]

For whatever its worth, I thought you folks might be interested in seeing a different take on the w/o thermostat issue...this person was replying to someone saying that not having the t'stat in resulted in less heat transfer...

"contrary to thermodynamic principles and not true...higher flow rate will INCREASE heat transfer in both engine and radiator, lowering temps.

perp is actually the 'impeller' found in most auto water pumps, designed to function with system HEAD (resistance) that includes a t-stat...deletion of t-stat often causes pump operation to 'go off the curve', impeller 'cavitates' and flow rate drops substantially...if t-stat is deleted, install a 'restrictor' orifice (basically just a flat washer, check your local circle track parts vendor) to 'stay on the pump curve', also GM Perf Parts 'had' (still ?) a cast impeller in 'std' rotation for ~$8 with better 'curve' ...for more detailed explanation, giggle 'pump curves' or N.P.S.H. (Net Positive Suction Head) or talk to any HVAC engineer"