diesel injector release pressure
 

I just completed construction of a pop tester from a bottle jack used as the power unit as per a very good and well illustrated how-to from this forum. Mine will not hold pressure and needs constant pumping. I guess I'll take it back apart and check my thread pin hole closures again. However, when I do rapid pump I am able to get up to about 100 bars and my first injector releases just before this value. Does anybody know what the proper release value is? And does anybody know what the penalty would be if the release pressure is too high?
Thanks in advance,

retrofitintl

135bar +/-2bar is ideal. any more or less and injection timing is affected.

higher is not bad as long as they are all at that same higher pressure +/-2bar.

More data on topic
 

Injector + Heat shield + Nozzle, Prechamber + Collar and Nailing. LINK THREAD
http://www.peachparts.com/shopforum/diesel-discussion/211750-injector-heat-shield-nozzle-prechamber-collar-nailing-link-thread.html

Without knowing what engine is involved, no.

Hi
I also just built a bottle jack pop tester. Mine wouldn't hold pressure either until I resealed the pin hole on the pipe with JB Weld. It still doesn't completely hold pressure but leaks down slowly enough it can be used OK.

I understand the non-turbo injectors are supposed to pop at 115 bar (1600 psi) and the turbo injectors at 135 bar ( 1900psi) - at least with the 617 engine.

I just started testing some junk yard injectors. pumping slowly, 3 of them popped at 1900psi and the other 2 popped at 1500 & 1700 psi.

But when I pumped fast - one of them popped repeatedly at about 1300 psi. I'm not sure what to make of this - perhaps dirt n the injector?

Anyway, I'm just learning too - and would be interested in what you find with your tester.

Regards,
Joseph

A few issues I can think are that the Hydraulic Jack normally uses thicker Oil; so Diesel Fuel may not seal as well. Next is Diesel Fuel could eat up the Seals.

Factory Made Diesel Nozzles Testers/Pop Testers do not use Liquid Dampened Gauges. And, when you are testing Injectors you want to watch the action of the undampened Gauge Needle/Pointer.

with Dampened Gauges tje action of the Gauge Needle/Pointer is slowed down. So, when you pump fast the pressure has will rise faster than the Gauge can show the Pressure rise.

On a Factory Made Nozzle Tester there is a manual Valve that cuts off the pressure to the Gauge. You shut the Valve off (to protect the Gauge) work the handle fast to get out the Air and open the valve so the Gauge gets pressure and proceed to do your Test working the handle slowly.
You can also close the Valve if you want to pump the handle fast or slow and just want to watch the spray pattern.