shiners780

Are the caps on the coolant expansion tanks a universal size?

I'm thinking of buying a coolant system pressure tester and was wondering if the attachments in the kits will fit our cars? I just wasn't sure if our caps were some unusual size or if a standard test kit would fit.

Any recommendations on inexpensive testers? It won't be used too often, so no need to go crazy on a top-of-the-line model.

Skip Wolfe

I have one of the Craftsman tester and the kit had an adapter that worked fine.

MyBlackCar

I have the Craftsman tester. The deluxe kit ($80) includes all the adapters, including ones that fit the expansion tank. There is an inflatable tip that seals the opening on the inside. Try finding one used if you can to save some money.

bearone

yes but early/late had different pressures.

late/13, early about 7.

if you put the hi pressure cap on an older car you'll get leaks where you never had them before.
btdt.

87951

Clint's 944

Go to autozone, free loaner tools and the testers have the adaptors included!

shiners780

Thanks for the info guys. The AutoZone loaner will do if I don't find my own by the time I need it (soon.)

I see a bunch of used Stant testers on eBay. Anyone have experience with them? Are they any good? They're selling for around $15-25. I figure if I can get one for under $30, it would be worth not having to drive to Autozone to pick up/drop off a loaner. And it would be nice to have one on hand "just in case."

Primarily I'm looking for one to bleed the system of air. I saw one being used at the track this summer, they said to keep it under 10psi and there will be no problems. Sound about right?

ELLSSUU

That's what I bought on Ebay. Worked fine. If you need I can go out and get the exact model number or a picture of the tool.

shiners780

Model number would be great! Thank you!

Looks like 255 and 270 are the popular items on eBay.

ELLSSUU

Mines a 270.

AR10

As a retired pro. car fixer I can recomend the Stant. I still have mine (after about 40 yrs of use).
Still works great.

xsboost90

how does that work? every car ive ever worked on had a pressure of 13-15 on the cap. early and late cars all supercede to the same waterpump, same resevoir, same block, head, hoses- besides a few jumper hoses and maybe the heater core they are the same. What causes a difference in pressure- does the antifreeze expand more in a late car?

theedge

I made my own, old cap with the spring removed and a schreader valve epoxyed in. Worked great till I lost it.

theedge

Heat. The water/antifreeze boils and builds pressure. A weaker spring releases pressure sooner. Hence when youve got random boil overs, first thing is replace the cap if its old. I dont know if early cars really did have a 7PSI cap though...

Granite 944

I also have and recommend the Stant tester kit. Great tool to have! You can also test your cap with it. The model number is #1270? Not sure, but if ya do a search on coolant pressure testers, or just on "Stant", I'll bet ya find tons of info posted by myself and many other satisfied customers of it. You'll never have a "air bleeding" problem, if ya have one. I bought mine at my local Napa dealer when I was in REAL need of it. I paid a little more for it that way, but I still don't regret it! All watercoolers should own one.

shiners780

Ya know.............now you got me thinking............

Would an expansion tank cap seal completely with the spring mechanism removed? If so...

What if I took an old cap, drilled a hole in it, JB welded a short aluminum adapter (tube) onto it. Then I could take my Motive Brake Bleeder, remove the brake reservoir cap from it (use a hose clamp to reattach later,) and clamp the "new" radiator cap onto the hose. The Motive Brake Bleeder could double as a cooling system pressurizer.

It's simple, cost probably $10 or less, and one less tool to haul to the track.

Think it'd work???