Hey all, I finally got around to building my injector pop tester. I may be using it wrong, so any input would be appreciated! The injector seems to begin "popping" around 400 PSI or so, and loses its pressure. http://youtu.be/hq5H-C-g8Bs Thanks!

For one thing, a liquid-filled gauge is not the best option for pressure testing. Its response time is too slow.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

I was told to only use the glycerin filled gauge. My spray pattern looks good but the pressures seem off. I may give a non-liquid filled gauge a try also.

Anyone else have experience with pop testing?

I use a glycerine filled gauge. It just dampens the response a bit so you get a more representative reading.

From what I can see it appears to be working as expected. Your popping is more pronounced than what I get, but I think that's just higher flow with yours. Are you popping injectors with new nozzles or just checking your existing injectors as they came out of the car? What are your readings across all injectors?

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

I did not watch the video but 400psi is too low. Turbo injector opens at 135 bar or 1958psi. Non turbo at 115bar or 1667psi. They are way off or you read it wrong. Cannot see anything wrong with liquid-filled gauges.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

2 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

I thought you might have meant it was 400 psi low until i watched the video and saw it chatter around 400.

How was the car running? and did you check your 0 to 60 before you pulled them?

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"NEW" 1984 300D TD needs some love

Not sure what, exactly, is being "represented." Except that it's not reality.

I suspect that you won't find a professional injector tester that uses a damped pressure gauge.

Can you show me a single, professional-grade injector tester that utilizes a damped gauge? Bosch? Bacharach?

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

Here we go again. It is wasting my time to response. I thought you are far better poster after a long period of hiatus.

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

2 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

Last time I checked this was a DIY-focused forum. If we all had access to professional-grade tools and instruments, we'd probably be in the business and have access to professional-grade documentation...though I'd argue that the forums are likely even better in many respects.

Regarding pop testers, if I felt I needed accuracy to +/- 1 psi on a pop tester, I'd buy a $5000 digital unit with integral printer, 16" screen and a .5 micron filter assembly and automatic popping and digital recording of each pop in super slo-mo, rather than building one. I can live with a lot less accuracy and bells and whistles and only have $21.47 invested...and you know what? The car runs perfectly, and has for the last 30k miles since I last popped my injectors.

I kind of like my HF tools, too... and my swap meet tools and my Craigs List equipment. And I kind of like making my own tools and solving problems without investing a fortune.

If you want a dry gauge, go for it...

__________________
Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

your popping appears to be around 135 bar... I don't know where you are seeing 400psi pop... it's over 1500psi... hard to tell exactly, as the needle is very slow to respond, but it's certainly not 400 psi...

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

This little unit has a liquid filled gauge:

Caterpillar Cat 1U6661 Pop Injector Tester w Cart Used | eBay

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1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge

also, the liquid level in the gauge makes it hard to read the pop pressure... but it's sitting stable around 1000 psi... it only pops as you pump it over 1500...

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

You make a great point!

For future reference, once the eBay ad expires...

Attached Thumbnails

   

__________________
Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

Can you make even the slightest hint of an agrument that would support the selection of a damped gauge for injector testing? The HF and Craigs List distraction isn't terribly persuasive.

Why would you choose a damped gauge for use in a dynamic situation like injector testing?

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

Uhhhh, because it works... oh, and because the multi-thousand professional Caterpillar units use liquid filled gauges. If it's good enough for Caterpillar, it's good enough for me.

...that is all

__________________
Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica