You don't need to go through all that... you can get an 'air hold' hose for
about $11 at Napa:

http://www.napaonline.com/MasterPages/NOLMaster.aspx?PageId=470&LineCode=SER&PartNumber=2992&Description=Air+Hold+Extension+Hose

or some other FLAPS.

For that matter the hose on my compression tester comes off and it already
has an air fitting on it:

http://www.autozone.com/R,NONAPP5440/store,5342/initialAction,accessoryProductDetail/shopping/accessoryProductDetail.htm

For about another $12 (at Home Depot) I got the rest of the stuff I needed
to turn the compression tester into a leak down tester.

Cya,
Robert

----- Original Message -----
From: "Mike Collum" <collum@VERIZON.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Saturday, April 14, 2007 6:25 PM
Subject: Re: 86 westy overheating issue

> What you're describing is one of the things a leak down tester does.
> Google leak down tester ... there are instructions for making your own
> and their uses.
>
> Mike
>
>
> Bob Mac wrote:
>> You might try this. The compression test may look good because if the
>> gasket is leaking into the coolant that mean the compression is backed
>> up by the coolant, hence no leak. We used this to replace valve springs
>> without taking the head off but i think it will work in this application
>> as well. Make an adaptor for your air chuck to fit in the sparkplug
>> hole. Use an old plug and break the porcelain off and braze on a male
>> end of the air chuck. Thread this into each spark plug hole one at a
>> time. make sure the valves are closed in that particular cylinder then
>> put the air on the adaptor. This will pump air into the cylinder and
>> should force air thru any gasket that is bad. you should see air bubbles
>> coming back into the coolant tank after a short while. Don't laugh try
>> it.
>>