im building a leak down tester and i cant find the valve that goes after the regulator. i believe it is a damper valve. does anybody know what the valve is called and where i can find it. i called one place that makes them but they wouldn't tell me what it is they just said to buy theirs. any help would be much appreciated.

thanks
keith

 

anybody? come on tech guys i know somebody out there knows this.

thanks
keith

 

This may help: Link

 

thanks for you link thats what im going off but on that page they say

The damper valve

“This necessary part is merely a restriction between the regulator and the gauge. The easiest way is to plug the middle pipe with epoxy and afterward drill a 0.040" (#60 1mm drill bit) hole.”

now is it just me or does that not sound like the best way to do it. i mean this is support to be a pretty precise tool and that just doesn't seem like all that great of a method to make one. but if .worst comes to worst ill do that

thanks again
keith

anybody else??

 

I bought a leakdown tester from Summit for $50 or $60 but I enjoyed reading the homemade leakdown link. As near as I can tell, the .040 hole diameter is not the critical part of the equation. It looks to me like it is just a restrictor to feed a minor amount of air into the guage. I don't think it matters if it is .037 or .044, just that it restricts the 100 lbs of air coming in so that if your guage is reading 97 lbs, you have a 3% leakdown. Without the restrictor, the 100 lbs of air coming in would overwhelm the guage and you couldn't get a good reading.
The link says to do your test at top dead cylinder, while the Summit instructions say to test at bottom dead center with the rockers backed off so that the valves are closed. I think the critical element in the equation is to control the 100 lb imput. If you only have 70 lbs imput then a 67 lb reading does not mean 3% leakdown. Most of the time, when you do a leakdown, you are in trouble anyway and you just listen to where the air is escaping. Last time I did one, I popped the radiator cap and it spouted up like "Old Faithful". I guess it didn't matter what the leakdown % was. Incidentally, in that situation, the compression test was perfect.

 

Thanks for the info I think I am going to get the test done tomorrow so we will see how it goes. I believe I know whats the problem is I just want to be sure before I start throwing money around.

thanks again
Keith

 

Let us know if your tester works.

 

this is kind of old but just to let you guys know i did build it. i built it just like the link but i add another gauge after the damper valve. it did work but when compared to my friends Snap-On on he bought it wasnt as accurate i did use a bigger drill bit to make the hole through the damper valve so that might have been the problem. anyhow just letting you guys know.

Keith