Ever wanted to pressure test your coolant system, but could find a adapter?

Well , when that doesnt work , since all the cap contains is a seal and a spring , we send the rubber seal seal the the us rubber testing institute the measure the level of elasticity , and they give us a 30 page evaluation , we then send the spring to a metalurgist the evaluate the spring on a molecular level , and request a full molecular evaluation . We can then , at that point rebuild or replace the failed components , and give the customer a full written evaluation .


" serenity now "

 

Then dont use chinese crap in your shop


" serenity now "

 

Thanks Brian for providing your insights on this and also posting the correct snap on adaptors as well.

Most of us do not do this every day and appreciate the information from those that do.

 

Amazing that this happens so often and yet it has never previously been a topic of discussion. If the cap isn't holding pressure and you get excessive localized boiling (I would not use the word cavitation as it has specific meaning) then coolant is going to be pushed out of the system for one simple reason, the resulting gas bubbles displace significantly more volume that the coolant which boiled to create them. If a car ended up with a hole in a cylinder then there was a much more serious problem, like the idiot owner didn't bother to check the coolant level. Yes, the problem may have resulted from a bad cap, but only because the owner ignored warning signs. Lots of idiots own Ferraris.

 

I would disagree that they are idiots. They have mechanics to check these things on their behalf at each annual service. Some owners prefer to spend their time doing other things like making money off the stock market, for example.

 

That was not an all inclusive comment. But believe me, I know more than one person who owns a Ferrari and, as far as automotive knowledge goes, they are idiots.

Anyway, I would like to point something out about cooling system pressures. The radiator cap is a differential pressure device. That is, it pressurizes the system to a given amount, about 1000 millibars or 15 psi above the local atmospheric pressure. The problem is that local atmospheric pressure varies all over the place. That attached chart shows some examples. LA is a particularly interesting example as if you are down around the beach you cooling system will be at about 2 bars. Drive up in the mountains and it will drop to about 1.6 bars. In psi we are talking between 30 psia and 24 psia. The boiling point of a 50/50 mix of antifreeze/water changes by about 3 degrees F per psi. At 30 psia it is about 267 F. At 24 its down to 249. You could argue that a guy who lives in Denver should run a cap with higher pressure setting than the guy in Miami. Might not be a b ad idea. The point is that there is a difference between a cap that holds pressure and one that doesn't and a cap that is out of spec by a few psi. There are bigger variations just by where you live.

Hate me if you want but physics is physics, reality is reality and BS is still BS.
Image Unavailable, Please Login

 

Kudos for posting this. I've been looking around for both parts and haven't been successful.
But following DrBob's snap-on link, I saw the apps were for
Vehicle applications include Volvo®, Saab®, Jeep®, Sterling® and Renault®
Use with TA26A radiator cap adaptor
See SVTS262B cooling system tester instruction manual for complete listing of specific model year applications

A quick search around Amazon found: Amazon for $35/ea

I just tried the cap adapter & it works fine on a stant tester.
I'm a lot happier knowing the cap is/is not bad rather than just randomly replacing it hoping it's the problem.

 

Oops, sorry. Amazon is like $43 and Ebay is $38. Watch shipping
7094 COOLING SYSTEM THANK ADAPTER JEEP SAAB RENAULT STERLING VOLVO
7107 PROFESSIONAL RADIATOR CAP ADAPTER JEEP RENAULT STERLING SAAB VOLVO

 

These appear to be 47mm x 3mm & 43mm x 3mm. Our cars are 45mm x 3mm thread.


I searched high and low and it appears only Snap-On offers a 45x3mm threaded male AND female combo to test the system and coolant cap.


Problem is a new Snap-On tester is quite pricey.


Anyone know if these Snap-On Adapters will work on other brand testers before I pull the trigger? I am skeptical of used older Snap-On testers as they could be reading inaccurately by now. I prefer a brand new tester.

 

When conversations get too stupid I just leave. Life is too short to deal with that. But it just caught my eye.

I see our brain trust has no idea of the connection between cooling system pressure and cavitation. A real problem in wet liner motors that we have been seeing for years but in many cases were unaware of what was causing it.
Pressure inhibits cavitation. Hence one of the reasons for pressure caps that maintain proper pressure. .