I know after my search that product is not very popular on this forum and for good reason but here is my problem.I have a external coolant leak on lower right rear of the engine which is more than likely a head gasket.Its a slow leak but getting worse i think.motor is running cool at 195 but i can smell coolant when exiting the truck.Im am going to have it fixed but i cant until after the the new year due to im low on $$$$$.
My question is this should just keep topping off the coolant or try the blue devil just to hold me over.
Thanks!!!!!!

 

I would personally try to get by topping it off and driving as little as possible. Head gaskets are expensive enough without having to replace a clogged radiator and heater core.

 

I would try a whole pack of the Barrs Leaks tablets. They are far less likely to cause problems than Blue Devil. They worked great on a similar leak on my truck, though my leak was very minor. It's been a year and thousands of miles with no issues. The tablets are recommended by GM for use in their vehicles, so I doubt there's any possibility of clogging. Just read and follow the directions (you can't put them in the reservoir, so you have to open a hose or crush them and feed them thru the bleed port).

I got mine at OReilly Auto Parts.

The Blue Devil has a rep for wrecking radiators unless they are new or very clean. I wouldn't take that risk. After the Barr's Leaks tablets I'd try K-Seal, which has a better reputation than Blue Devil.

Years ago I had the Cargo stop leak with what looks like brass in the bottle fix a pretty significant radiator leak that never came back. So that would be my third choice. But it could be just a gooey as the Blue Devil, so I'd try the tablets or K-Seal first if you can find them.

BTW, I'm sure Blue Devil works in some situations, but our radiators are so prone to clogging it seems like a bad choice for our trucks.

 

thanks for the info gonna try it!!

 

"I have a external coolant leak on lower right rear of the engine"
Are you sure it isn't leaking from a soft plug in block? They were designed to push out if coolant were to freeze, or nearly freeze up in cold weather, so as to not destroy the block, if freezing happened. Sometimes they just come loose over time, and leak. They are not hard or difficult to replace, if you are able to get access to them. If that is your problem, I wouldn't fool around with liquid miracle stop leak workers, but would just top up coolant, as needed, after checking it before EVERY trip, until you are able to tend to the problem, whatever it is. Most importantly, don't let coolant run down, or you potentially are risking serious problems.

 

I will check that out first.Can you please tell me where they are located
thankyou

 

That's a good point about the location of the leak. I read that and thought, 'hmm, wait a second' but then got distracted by the stop leak question.

However, I'd still run the tablets if he can't get it fixed ASAP. They will possibly stop what ever the leak is until it can be addressed, and running low on coolant and overheating is more likely to happen with a active leak.

In any case, I'd watch it like a hawk from here on out. I still check my coolant almost every morning, just because it's a habit at this point.

 

Let's backtrack a bit.

What you need to do is rent a pressure tester from Advance Auto (their kit definitely fits our truck). You basically have to buy the kit but then they give you a full refund when you return it. You attach it in place of the coolant cap, pump it up (I believe 20psi is the correct pressure for our truck), then take a flashlight and examine all the hoses, the water pump, the radiator, and the front and back of the heads. In this case, also look at the engine plugs. You might see coolant spraying out, or it could be a trickle. Or if it's like my head gasket, it is such a tiny leak you can't see it at all even under pressure.

But the pressure tester is useful because it tells you A) how bad the leak is and B) where the leak is. Then let us know what you find.

 

To add to Dr Mordo's recommendation for a pressure test is to add food grade fluorescein to the coolant, it only take a teaspoonful or two and then search for the leak using a UV lamp as it is fluorescent and shows up brightly in low light conditions. Also it won't harm your cooling system or engine. Great stuff for hidden leak detection, used in the petro-chem industry a lot.

 

Nice tip!