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-   -   I know this sounds crazy but... (http://www.peachparts.com/shopforum/diesel-discussion/391414-i-know-sounds-crazy-but.html)

Father Of Giants 02-07-2018 06:22 PM

I know this sounds crazy but...
 
Can you tell the general health of an injection pump by listening to it?

I tried this a week ago, some of them sounded authoritive like deep and hollow drums, while other where far more vague/soft/anemic in sound.


Is there any bearing in this?

tdoublenastywitit 02-07-2018 07:45 PM

Where did u do this??

Diseasel300 02-07-2018 07:51 PM

You can tell if the delivery valve is seating positively or not. You should hear a "click" every time the cylinder fires if it is. If you hear a squeak or no click, you know the DV isn't seating. Use a good mechanic's stethoscope.

There's also a couple of ball bearings on the camshaft in the IP. Listening is one of the ways I determined my original IP was toast. You could hear it knocking in the governor section. Upon teardown, the rear ball bearing had failed.

Father Of Giants 02-07-2018 08:03 PM

Quote:

Originally Posted by Diseasel300 (Post 3786905)
You can tell if the delivery valve is seating positively or not. You should hear a "click" every time the cylinder fires if it is. If you hear a squeak or no click, you know the DV isn't seating. Use a good mechanic's stethoscope.

There's also a couple of ball bearings on the camshaft in the IP. Listening is one of the ways I determined my original IP was toast. You could hear it knocking in the governor section. Upon teardown, the rear ball bearing had failed.

Thanks, I'll listen again. Just need to buy another stethoscope.

Also what should a healthy waterpump sound like?

BillGrissom 02-08-2018 11:28 AM

I don't know how you could judge leakage past each piston in an injection pump, other than removing it and testing it on a Bosch machine. One guy here was investigating measuring the pressure pulses on-car via sensors on each injector tube, but that is a science project (piezo sensors or strain gages w/ high-speed data acquisition).

One might rig a tubing system w/ injectors to test it on-engine, collecting each spray in a graduated cylinder, as one does in gas engine injector testing. That would at least tell if the circuits are balanced in volume. One needs injectors on the tubes to build up back-pressure.

Balance is critical in gas engines since the fuel control has a single O2 sensor to adjust multiple injectors (or at least 1 per engine bank), so assumes all are balanced to control the proper O/F in each cylinder. A diesel fires over a wide O/F range, which is why it runs WOT (i.e. no throttle plate to control air flow), so I expect balancing the cylinders would mainly affect how smooth the engine runs. Of course too much leakage also limits max fuel flow and thus power.

jake12tech 02-08-2018 12:54 PM

Hey if it runs good and delivers fuel, don't go poking where you don't need to. Enjoy it and drive it. If it ain't broke don't fix it.

Father Of Giants 02-08-2018 09:43 PM

Quote:

Originally Posted by jake12tech (Post 3786989)
Hey if it runs good and delivers fuel, don't go poking where you don't need to. Enjoy it and drive it. If it ain't broke don't fix it.

It actually runs HORRENDOUSLY at start up, glow plugs are fine, the engine is worn out(head or block ?), maybe the IP has problems. The car has had this same behavior since day one.

Even at full operating temp it sometimes has the hickups. What I do know for a FACT is cylinders 2 and 6 are at fault, had a video covering this. Why are they performing horribly, no clue.


Tried multiple times to do a leakdown test but failed because I don't know how to line everything up.

torsionbar 02-08-2018 11:50 PM

Quote:

Originally Posted by Father Of Giants (Post 3786909)
Also what should a healthy waterpump sound like?

My rule of thumb on water pumps is replace by default if it's more than 10 years old. If you don't know how old it is, assume its original. Same for all of the coolant hoses, since its much easier to replace pump and hoses all at once. The parts are inexpensive, and a failure will leave you on the side of the road and/or cook your engine, so I err on the side of caution here.


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