Ok, I have either a blown head gasket or a cracked block. I won't bore you with details, just trust me on it. If its a gasket the minimum cost looks to be $2,000+ and I don't even want to think about a cracked block. I can't be sure which it is without tearing the engine apart.

Here's the question: Has anyone tried Thermagasket for head gasket repairs? http://www.rxauto.com/. I'd like to hear from people who have actually tried it.

RxAuto claims their product fixes most head gaskets and cracked blocks permanently without tearing the engine apart and works on all engines, including diesels. It only costs $189. Let's see - $2,000 or $189, $2,000 or $189...I've decided to try the Thermagasket! My first thought is it has to be snake oil, but the temptation to try and save $1,800+ is mighty strong. They also claim that if it does not fix the problem they will refund my money and I'll only be out $20 for shipping. I looked long and hard to find reviews of this company (rxAuto) and its product (Thermagasket) but surprisingly there is almost nothing online. I only found two old user reviews - one positive and one negative.

I'm going to try to repair my leak over the next week using this product. I'll keep everyone posted on how it goes and how easy it is to get a refund if it does not work. I figure even if it is a total waste of money at least there will now be some information posted about it on the web.

Do the R&D if you wish, but replacing gaskets yourself isn't that difficult nor a expensive proposition, with history some of these have especially with single stat lower flow, it mite be prudent to pull the heads, this stuff may work, or it may hide a pending larger issue, and won't show until most inconvenient time. say on vactation or hooked up to a expensive trailer hundreds or maybe thousands of miles from home, wife & kids B1tching if it goes bang takes out the crank, etc.

Is the price difference worth the consequences, it's managed risk to be sure, just make sure you can afford the consequence if it doesn't work as advertised.

It would be an interesting prospect to isolate which head has the leak pull that one, see if it's minor or major, problem, and run the leak stopper.

If you go this route put plenty of close to home miles on it after applying it, monitor engine like a hawk, until you are satisfied it really is fixed, vary speed levels & load.

Nothing can match replacement of broken/worn mechanical part with new, but if you are really in a bind do keep us posted how you make out. take good notes and pics along the way.

I'd be more impressed with the warranty that said if the engine fails after use they would cover engine repair

I just read their instructions for installing it make sure they know it's a Diesel you are trying to repair, the "baking speed" I'll call it is 2500-3000 rpm is pretty fast for a Diesel with suspect cooling, see why they want that rpm I suspect to get it hot, I'd feel safer 1500-2000 rpm for the 6.5. Maybe I'm over cautious but I would not want to to be their guineau pig

I just read their instructions for installing it make sure they know it's a Diesel you are trying to repair, the "baking speed" I'll call it is 2500-3000 rpm is pretty fast for a Diesel with suspect cooling, see why they want that rpm I suspect to get it hot, I'd feel safer 1500-2000 rpm for the 6.5. Maybe I'm over cautious but I would not want to to be their guineau pig
Great point Doc, I didn't think of that - it is pretty fast. I bet those RPM are for a gas engine. The online instructions you read (http://www.rxauto.com/application.htm) don't mention that the thermostat has been removed for this step. Engines at idle would have a hard time getting hot with no thermostat so that's probably the reason for the RPMs. Their tech support is readily available so I'll discuss it with them. If it's just to get it to operating temp and keep it there I'll run it at a more sedate "diesel-appropriate" speed:). Its not like diesels have any trouble getting hot.

Do the R&D if you wish, but replacing gaskets yourself isn't that difficult nor a expensive proposition, with history some of these have especially with single stat lower flow, it mite be prudent to pull the heads,
I may go that route if this stuff doesn't work. This being a van though I know engine work is a real headache compared to trucks.

If it sounds to good to be true it probably is !!!!!!!!! I'm not to much into bandaids but lay the simptoms on us so we know what you're dealing with.

If it sounds to good to be true it probably is !!!!!!!!! I'm not to much into bandaids but lay the simptoms on us so we know what you're dealing with.

OK, here goes...
1) sometimes when starting it runs rough for a few seconds while white smoke pours out of the exhaust then clears up (coolant being cleared from a cylinder?).
2) Within 60 seconds after starting cold the coolant system will be pressurized (from exhaust gases being forced into coolant through the leaky gasket?)
3) after running at speed for a few miles coolant starts leaking out of the expansion tank (exhaust gas in coolant overpressurizing the system?) Eventually (30-45 minutes) enough coolant will have been blown out that the engine starts overheating.
4, 5) there doesn't seem to be any coolant in the oil so its not as bad as it could be, and coolant only leaks from the expansion tank when hot so it isn't a slow coolant leak.

Normally I'm the first to agree about stuff that seems too good to be true, and if the cost were about the same I wouldn't consider it, but it seems worth a try. In theory it will only cost $20 for shipping it if fails to fix the problem and $200 if it does.

Most all 6.5 heads crack between the intake\exhaust valve - most do not leak.

The occasional one that does leak results in that same symptom - compression\combustion pressure into the water jacket.

A repair kit is available, but restricts the water flow between the valves and the IDI combustion chamber, so not good for an engine with enhanced power rating.

I'd be sceptical of anything that bakes itself onto the water jacket - seems as tho it would reduce thermal transfer throughout the system after it 'sets up'.

Even in the radiator.

Do the R&D if you wish, but replacing gaskets yourself isn't that difficult nor a expensive proposition
This is a bit off topic, but how hard is this really? I'm no mechanic but not a complete dork either (I've done tune-ups, replaced belts, brakes, shocks, struts, etc on my many cars over the years). Is it basically just removing the head bolts, pullig the head off the block, replacing the gasket and then re-installing the head (tightening the bolts in the proper sequence with the proper torque of course)?

Not even off-topic, but basically, yes................

Not even off-topic, but basically, yes................
I'm just hoping the thread stays a Thermagasket thread instead of morphing into a head replacement thread.

So it sounds like even including removal of both the intake and exhaust manifolds this is a basic brute force mechanical thing to do with no finnicky tolerances or special tools required? If the engine were on a stand I'd go for it, but I'm a mite worried about trying it in the confines of a van.

thermaweld offers the same thing, except they come to your door and install it and if it does not work, they refund your money as well, I've never used it but have been tempted....

$2,000 tofix the heads right, $200 for Thermagasket unknown what it will do to the motor, $4,000 for a long block if the Thermagasket screws someting up. I guess it's up to you but I would fix it right.

I had the same puffs of white smoke, and thought about the quick fix... Now, I'm glad that I didn't. I had two cracks in each head.