Awhile back I posted about dealing with a mystery blown head gasket. Wasn't mixing oil/water but it was steaming out the tail pipe. I had tried the green "nanotechnology" bottle but it didn't work, and someone mentioned trying the blue devil fix in a bottle. So I picked up a bottle a few weeks ago, and finally got around to putting it in yesterday. Within 10 minutes the steaming out the tail pipe had all but stopped. So I let it sit overnight after the treatment, and this morning I reinstalled the thermostat, refilled the coolant, burped the system then took it for a ride. 20 miles later, no steam, no oil/water mix no tow truck ride home. Car runs good, heat still tries to burn you out of the car. I'm a believer. Thanks for the tip!
Now to see how long it holds up.
Depending on the car, it could horse-berkeley the rubber in your heater control valve, as it did in my 2007 BMW 525xi. It took a few weeks, but the rubber swelled up so badly it blocked passages and heat went cold. It also gummed up the coolant passages in my trans cooler thermostat, which caused a “TRANS OVER-TEMP” DTC and could have led to a very costly disaster if I couldn’t pull over and shut it down.
So I recommend a drain and flush with distilled water, followed by a fresh fill of a the appropriate coolant mix.
Yeah, that's the plan. Currently it's filled with good old Florida well water, which is full of lime and calcium. I figured I would give it a few days of around town errands and then flush the daylights out of it, and load it back up with proper coolant.
Robbie
UltimaDork
11/29/18 4:49 p.m.
I dunno if I told my story in your other thread or not (I've told it before here a few times I'm sure). I'm also a blue devil believer.
Back in maybe 2011 or so, I was racing a 24 hr chump race in an E36 6cyl. Maybe 1 hr into the race we were having overheating issues. Eventually diagnosed as a blown head gasket that was leaking engine compression into the water jacket, super-pressurizing the coolant system and preventing coolant from circulating.
We went to the parts store (even though there was probably no way we were doing a head gasket without the cam holding tools) in rural Colorado on a Saturday, and of course they didn't have a BMW headgasket in stock. The kid behind the counter took pity on us, and said "how bad do you want to fix it? $50 bad?" We bought the blue devil for $50 and went back to the track.
Follow instructions on bottle. Pour into coolant, idle engine for 1 hour, done. So we did.
And then we raced without further issue for 17 more hours, not being gentle on the thing. The car also was rented and then sold to another team (with full disclosure of the blue devil) and ran at least 2 more full crap can weekends without more hg issues.
I wrote in to the makers of blue devil, and they sponsored our next lemons race (vinyl wrap for the car, swag, and tons of blue devil product - ha!) in the blue devil Miata. I have some pics I will try to dig up.
Stepfathers Saturn wagon with a couple hundred thousand miles needed a head gasket. He uses it as a DD (retired) and has also dragged it (flat tow) all around the country with their motor home. He'd bought it new and always kept up with maintenance (done by shops). It isn't rusted or beat up looking & so debated whether or not to spend much on such an old car with so many miles. They're several states from me so he called me for my opinion being the family "car guy". I told him just do Blue Devil and junk it if it doesn't work out (he can easily afford a new car). Been probably 3 years now and he's still driving it. I'll guess he's put 30,000 or more miles on it since the treatment.
Neighbor used it on a 3.0 (more notorious for head gaskets than even certain Subaru’s) in his Lebaron. Not sure on how many miles he put on it but it gave him probably an extra 2 years of driving it before he sold the car (still driveable).
Came in here expecting corvette talk.
Gratefully disappointed.
Will have to remember this stuff works.
I'm putting this thread in my watchlist to remind me after the cpo warranty is up on the Forrester and the headgaskets go out I can use this stuff.
SVreX
MegaDork
11/30/18 7:42 a.m.
Off topic....
How come all the Gainesville guys now go by “Mr”? 
Robbie said:
I dunno if I told my story in your other thread or not (I've told it before here a few times I'm sure). I'm also a blue devil believer.
Back in maybe 2011 or so, I was racing a 24 hr chump race in an E36 6cyl. Maybe 1 hr into the race we were having overheating issues. Eventually diagnosed as a blown head gasket that was leaking engine compression into the water jacket, super-pressurizing the coolant system and preventing coolant from circulating.
We went to the parts store (even though there was probably no way we were doing a head gasket without the cam holding tools) in rural Colorado on a Saturday, and of course they didn't have a BMW headgasket in stock. The kid behind the counter took pity on us, and said "how bad do you want to fix it? $50 bad?" We bought the blue devil for $50 and went back to the track.
Follow instructions on bottle. Pour into coolant, idle engine for 1 hour, done. So we did.
And then we raced without further issue for 17 more hours, not being gentle on the thing. The car also was rented and then sold to another team (with full disclosure of the blue devil) and ran at least 2 more full crap can weekends without more hg issues.
I wrote in to the makers of blue devil, and they sponsored our next lemons race (vinyl wrap for the car, swag, and tons of blue devil product - ha!) in the blue devil Miata. I have some pics I will try to dig up.
Yeah, it was your post that inspired me to try it out. Glad I did.
OK my truck has a little HG leak it appears.... Blows the coolant out the overflow on the freeway, does fine around town.
Do I dare try Blue Devil?
Would you use it on a car you want to keep for 3-5 more years?
Directions say to drain coolant, pull Tstat, fill with water, add blue devil and idle 50 mins. Replace T stat, drain off enough to fill with coolant and replace T stat.
My thinking was give it another good flush after the treatment and refill with new coolant. Might be less chance of it swelling the rubber in the system is its not left in long term?
knock on wood but I haven't had any further issues with the car since the treatment. In fact we're now planning an engine rebuild for it when I find another core engine to bench build and drop in.
I did just that. remove t-stat, apply treatment, drive for a few weeks with it in the system, drain, flush, replace t-stat, fill with 50/50. So far so good, and I've taken it 2 hours away and back with no issues.
In reply to Mr. Lee :
I was thinking one day in the system...... This is my DD, and I want to be able to drive a few states away and not worry about it. But getting to the HG's is a project itself..... And if I am in there I will have to do timing chains, WP etc. Parts add up fast! Im looking at $800 for non OE stuff.
Robbie
UltimaDork
2/4/19 5:15 p.m.
I'd absolutely do it.
But I also dd cheap cars...
I agree with Robbie, I would do it. you can flush it out and at worst it doesn't work, at best you don't have to worry about it again.
Thanks guys. I will try it and give it a flush maybe one day driving? It's not going to be above freezing for awhile, makes not having coolant bad....
has anyone tried this to "fix" a leaky heater core?... my cherokee has a leaky heater core and I'd be willing to spend the money in hopes that it seals it...
I'm in houston so having a super efficent heat isn't a big deal but I want to have SOMETHING... I've also read of some people putting the core into it's own loop and using some of the other stop leak potions (alu seal type crap)... to fix them without gumming up the entire engine... but the blue devil sounds like it might be the best option?
Ive had good luck with nutmeg for heater core leaks. The powdered version, not chunky.
One other thing I did with the Blue devil. I ran it with straight water. I had been trying to work on the car previously and drained it of coolant. That might have made the difference in how it worked/didn't swell stuff. Just a thought.
They say to drain and flush and fill with just water for the treatment.
hmmm, I used the pour and go treatment. May be a different formula, as I'm pretty sure that one says it's ok to use with coolant in the system. Either way I would go with it.
