another injector pop testing thread...

[icanfixall]

Something that has never been published about the precups is they ARE NOT touching the cylinder head. The walls are clearanced from the cup bore but the top and the bottom lip do touch the head. I believe this non touching has a lot to do with keeping the precup temp up high enough for a better burn of the fuel being sprayed on it. Your gauge with 200 lb divisions is not going to tell you much at all. I can send you a factory pop tester like you see in my vids. You will need to repair it but I feel you have the machinist ability to do so.

 

[mblaney]

Don't worry about a screamer Remember that your pop tester is jamming a higher volume of fluid through, that is causing the noise.

 

[IDIoit]

the one I call a screamer, is obnoxiously loud.
it was 10x louder than the other 15 I tested.
guess I just don't know jack squat lol

 

[OLDBULL8]

That screamer could very well be that the injector popped at whatever PSI, but the needle did not open all the way causing the fluid to scream past the opening. I've had that happen when the needle only opens a couple of thousands and your still pumping fluid thru it. At least that's what I think it is, cause I found that the needle was hung up when I went to adjust the pop pressure and had to work it out. The needle clearance is so close, I think a fingerprint will hang them up.

 

[Shawn MacAnanny]

I am thinking about building one of these with a high pressure hydraulic piston chemical injection pump. I think i have one laying around. They can have an almost infinitely variable dosing stroke from say 1ml to 200ml or so. I bet that'd be ideal for pop testing injectors. I think the spare i have is rated to 2000psi, which means itll probably go to 2500. where are you guys getting your fittings for the top of the injectors? Just using an old fuel injection line end and compression fitting it with a stainless line or something?

 

[79jasper]

Most I have seen use a old line.

Sent from my SAMSUNG-SM-G935A using Tapatalk

 

[mblaney]

... where are you guys getting your fittings for the top of the injectors? Just using an old fuel injection line end and compression fitting it with a stainless line or something?

Any decent hydraulic shop will have it! That is a metric fitting, I forget the specs but I know I posted the size in my pop tester build thread. This is an off the shelf part. Take an injector into your local shop and ask for a fitting, tell them it is a metric - they should recognize it immediately. I got mine from a Parker supplier.

Edit: injector thread is 12mm x 1.5 pitch