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Doing my nozzles in a weekend or two with a good friend whose a diesel nut, but not a certified tech or anything. Hes done a handful of 2nd gen 24v injectors, 12v work, fuel systems, turbos, etc.

Anyhow, were doing the nozzles soon. I do not know what an injector rattle or bad injector sounds like, my first diesel. I've read plenty about cracking injectors from RP (IE: MP8) etc. So my question here is, besides taking the injectors out, installing nozzles, driving 2 hours to the closest place that flow tests (waste a half a day) Is there a physical way I can look at the injectors after I clean them up really good and say WOAH this ones going bad, like is a bad injector visible I guess is where I am getting at..

I have no symptoms.. no white smoke on start up, no diesel fuel in my oil, no rough starts no bad idle, but I got a rattlin diesel engine under the hood, and I just want to cover all my bases here.
 

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lets see i have had 4 sets go bad and they never showed anything visible
 

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There really is no way to look at an injector and say for certain that it is bad unless it is blown all to hell. And i mean it is missing chunks or there is a definite crack in it. The holes for the diesel to flow through are so small that you cant put a needle through one. The only way to really know is to take them out and have them tested. A buddy of mine has a really expensive code scanner and he can tell me which one is not performing correctly. Thats only if its running so bad that it throws a code. My powerstroke i couldn't tell when one injector went out, so much. But when two went out there was a definite miss in the idle and white smoke. When the third one went out when i went to buy the injectors, there was a cloud of smoke behind me.
 

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Like the others are saying the only true way would be to get them tested. I know you're saying you don't want to do it but you will have to, to find out for sure. Have you considered whole new performance injectors inside of tips?
 

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A quick test is to measure the resistance with a multimeter. Anything over 1 ohm and most likely the injector is bad. I tested mine this way and all but #5 were 1 ohm or less. #5 was 2.6 ohms (hot) and 2.1 ohms cold.
 

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Discussion Starter #7
A quick test is to measure the resistance with a multimeter. Anything over 1 ohm and most likely the injector is bad. I tested mine this way and all but #5 were 1 ohm or less. #5 was 2.6 ohms (hot) and 2.1 ohms cold.
Can you tell me more about how you did this?


And as far as buying new injectors to the other post, got the nozzles for a heck of a deal, so can't really afford the huge pricetag of new injectors
 

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Can you tell me more about how you did this?


And as far as buying new injectors to the other post, got the nozzles for a heck of a deal, so can't really afford the huge pricetag of new injectors
Disconnect the valve cover gasket and remove. Set your multimeter to Ohms and check the terminals at the top of each injector.
 

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Disconnect the valve cover gasket and remove. Set your multimeter to Ohms and check the terminals at the top of each injector.
If your going to ohm out the injectors you need to take the wires off first.
 

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Testing the resistance only tests the solenoid. You can have a good solenoid with a cracked injecor.
True. I was just giving him something to start with.

If they all check fine as far as resistance, then you will have to send them out to get tested.
 

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Like the others are saying the only true way would be to get them tested. I know you're saying you don't want to do it but you will have to, to find out for sure. Have you considered whole new performance injectors inside of tips?
Is that what a flow test is?
 

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The coils on the common rail injector don't give much trouble. The problem is the control valve on the injector wears an the return increases. This is the item that has to be repaired.

The only problem. Is that Bosch dent sell the item to the open market. The nozzles can be a problem. Normally the high fuel return is a sign that the injectors need replacing.

The high return causes timing problems with the injector. This can only be fixed with. Remanufactures injector.


The test procedure is displayed in the tech form. Some has laid the process out in detail. If you have high return you will be waisting your money doing anything but replacing th injectors with properly working injectors.

A quality injector will cost you between 300 and 400 dollars. If you buy anything cheaper you are probablly buying a what we call a spray and pray.

The new nozzle and control valve will cost a high column remanufacture more than 100 bucks. If these item aren't replaced the life of the injector is limited from the beginning.

With the 100 cost they will have reman cost. The equipment to reinstall the parts is extremely high. The testing equipment can coat as much as 100,000 dollars.

To be able to buy a injector for 300 is a deal.

Their are only a few injector remanufactures that have e resourceds to produce this product to a lecfel that eill hold up long term.

Bosch
Cummins
Bostech
Mopar

And a few of the bosch central distributors can reman th product in house

Bosch is slowly getting distributors to invest in the equipment to rebuild the injectos. The cost is over 500,000 dollars to be able to reman this item correctly

I hope this helps. The typical price for testing common rail injectors is about 40 to 50 bucks.

Doing this could help you to only have to replace the work of them.

A good thing to do to extend the life of the injector is us a 2 micron filter. I am told that the oem filter is 10 microns
 

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Would a high return flow rate (over 180ml/minute) cause over fueling or excessive black smoke?
 

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checking resistance doesnt always show a bad coil. You can have a bad coil and resistance can be in spec, resistance is not really the best method of checking a coil. Best way is to take it to a fuel shop who is qualified to work on them and has the proper equipment.
 

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Their are only a few injector remanufactures that have e resourceds to produce this product to a lecfel that eill hold up long term.

Bosch
Cummins
Bostech
Mopar
So you are saying that Mopar remans their own injectors? I just had all 6 replaced under warranty ... one was bad (#6) ... replaced again and now my Cummins rattles something terrible. Driving me nuts.
 

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sure your Dodge dealer shop boys put in the correct year group spray pattern 5.9 rebuilt injectors/nozzles?
with those pinhead contractors south of the border, never know what's in the box.
maybe someday we Americans will demand made in America quality again.
or get a Toyota death trap:chainsaw:

better plan on 6 NEW real Bosch when Bosch gets their injector manufacturing business up to speed. they are well behind OEM engine manufacture injector demands now.
will be months, probably next year before they think about 5.9 new injectors on the line.


So you are saying that Mopar remans their own injectors? I just had all 6 replaced under warranty ... one was bad (#6) ... replaced again and now my Cummins rattles something terrible. Driving me nuts.
 
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