Checking Check valves....
#1
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Checking Check valves....
i want to go through and check all my check valves included in the rats nest and motor. how do i go about doing so? do i need a tool?
#3
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I would recomend getting a Mityvac vaccum pump and apply 20inhg of vacuum
in the opposite direction that the arrow is pointing and make sure it holds that
vaccum for at least one minute. The blow test is ok for really bads ones but is not
good for ones that have small leaks. I got my Mityvac at Autozone. They had a
free rental one for use.
jaj1
in the opposite direction that the arrow is pointing and make sure it holds that
vaccum for at least one minute. The blow test is ok for really bads ones but is not
good for ones that have small leaks. I got my Mityvac at Autozone. They had a
free rental one for use.
jaj1
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All of mine seemed good using the blow test, hooked it up to a Mityvac and 3 had slow leaks... Since 3 outta the 4 check valves go into the UIM and flow in the vacuum direction, just make sure they hold at least 10psi of checked pressure if your car's mostly stock.
#7
Originally Posted by jaj1
Maybe the easiest but it is not a good test.
You need a full 20" to full test the check valves. I too had a few that passed the mouth test but were bad.
Sonny
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#8
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Damn I read the title and thought you wanted to check your valves. Not your check valves. I was hoping for a roasting.
Any how since I am here I would say if you have the money to buy a vacume tool go that rout but if not you can check them with your mouth. You should be able to blow thru them in one direction only.
Any how since I am here I would say if you have the money to buy a vacume tool go that rout but if not you can check them with your mouth. You should be able to blow thru them in one direction only.
#9
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Your mouth can apply very little pressure/vacuum. You'll want to be sure they don't leak against 10-15psi of vacuum (pressure). A mityvac pump works best for this (and many other things on this car). If you're not interested to do that, then just buy all new replacements from the hardware store. No sense losing the kingdom for the sake of a $3 check valve.
Dave
Dave
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Whoa... fancy-schmancy!
Did you happen to notice vaccum pressure it takes to open those suckers (in the on/open flow direction)?
I had to place some checkvalves in a supercharged Miata to keep pressure from going where it wasn't supposed to go. I used a large one in the ISC breather line that wouldn't open until like 3inHg (obviously should be 0, ideally). When it did open, the diaphragm would actually vibrate, and would sound like a trumpet being constantly blown when the A/C was on. It took me a week to find the source of the noise.
Did you happen to notice vaccum pressure it takes to open those suckers (in the on/open flow direction)?
I had to place some checkvalves in a supercharged Miata to keep pressure from going where it wasn't supposed to go. I used a large one in the ISC breather line that wouldn't open until like 3inHg (obviously should be 0, ideally). When it did open, the diaphragm would actually vibrate, and would sound like a trumpet being constantly blown when the A/C was on. It took me a week to find the source of the noise.
#14
Call me gramps!
Originally Posted by EpitrochoidMan
These guys are indestructable:
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