Engine/Transmission (1994 - 1998) Injector removal / replace

[SteveAnsley]

I'm going to pull my injectors this weekend and have them pop tested - I'm having trouble w/ blue/gray smoke at idle - even when fully at temp.



I'm going to use the short piece of pipe w/ a 14x1. 5mm bolt to pull them.



My questions are regarding reinstalling.

1. Do I just reinstall all the lines and crank until she fires or do I need to leave the lines 'cracked' until I bleed the lines of air?

2. What size is the hold nut nut for the injectors? ie: what size socket do I need?



Any other suggestions are appreciated.



BTW

The nice part is the shop that is recommended for testing is in the same block as my office - litterally around the corner.

They charge $9. 54 per injector to test and $23. 10 per injector to re-build - sounds reasonable to me. Is this the norm?

 

[TRCM]

15/16ths deep well socket



I didn't bleed mine, just started it, and she ran rough for about 45 sec, then smoothed right out

 

[Vaughn MacKenzie]

Steve, tell us a little more about your truck. Are you running bigger injectors, got a thicker than stock head gasket, etc.



I think it's worth your time to pull and at least clean your tips (just brush them off with a wire brush) since 12v injectors seem to build up a lot of deposits. Pop testing is a good idea too.



Did this issue start gradually or fairly sudden?



Vaughn

 

[SteveAnsley]

Vaughn,



I bought the truck about 9 months ago - engine is stock from all indications, tamper-proof screw is still intact on the afc housing. Currently 120,000 on the clock.



It's been smoking for the last couple weeks, seemed to come on rather suddenly - not completely sure. You can see the blue/gray smoke and the the fumes are rather obnoxious.



I don't see any smoke while cruising, but I don't have the best vantage point - going to have the wife follow me tomorrow to watch.



The truck seems to run fine otherwise - no noticeable loss of power.

All the filters are clean (fuel, air, oil) I replaced the prefilter screen about 8,000 miles ago.

It has a new overflow valve from about 4 weeks ago - pulled it yesterday, the spring is 5/8" long.



The crankcase oil level has been dead on, checking the dip stick.



I was first thinking the timing has slipped, but when calling different shops - the consensus is to check the injectors.



I don't have gauges yet (yeah, I know) so I'm a bit blind regarding engine parameters.



Wire brush? Being carefull not to brush depris back into the tip, I assume.

Brass or stainless? Or does it matter?

Or is it a good idea to pop test them anyway?

 

[RJPotts]

I'll doubt pretty highly that you'll be able to brush anything back into the orifii in the nozzle. Those are some pretty small holes. Otherwise, any wore brush should do, along with some carb/brake parts cleaner.

-R. J.

 

[Vaughn MacKenzie]

Steve I've used a stiff wire brush on mine. Like RJ says the holes are pretty tiny, any little debris that does get in the holes will be blasted out instantly on startup.



If cleaning injectors doesn't solve the problem then I would service your prefilter assembly. Clean it, replace the O-rings, including the one over the heater puck. Check your fuel heater with an ohm meter too, if it's burned out most likely it is leaking and sucking air. That will definitely cause blue smoke.



More details here http://www.nwbombers.com/forum/index.php?showtopic=15869

and here http://dodgeram.org/tech/dsl/filter/pre-filt_clean.htm



Vaughn

 

[SteveAnsley]

I picked up a 15/16 deep well socket on the way home tonight - why in the world is everything else on the engine metric, but these nuts are sae. Doesn't matter, I know.



Are the copper washers used under the injectors and along the fuel and return lines all re-useable?

Best to replace them anyway?

 

[Vaughn MacKenzie]

I've gotten away with reusing them, but at your miles best bet is to get new. They are fairly inexpensive, get them from Cummins, Piers, or check around for any injection shops in your area. . . they might have them.

 

[SteveAnsley]

OK, even when I'm having trouble (blue smoke) with this truck - I enjoy it.



This could not have been any easier - brings me back to high school and my '71 Camaro, just as easy to work on. The 'worst' thing today was having to re-attach the battery in order to roll my window back up.



The injectors looked like complete 'crap'.

I'll drop them off Monday and have them pop tested.

#ad




I'm planning on replacing the square cut o-rings on the hold down nuts. Their not in the best shape and I assume they are there to minimize leaking. Or, are they just a spacer and not that big of a deal?

 

[Signal73]

I think they are strictly there to prevent water from seeping down into there Either from road spray or engine washing and causing the hold down nut to seize to the injector body. Only thing I could figure...

 

[SteveAnsley]

Follow-up question.



Would you'll recommend having the injectors pop tested or just cleam them and put them back in w/ new washers?



Is it common place enough to have a problem w/ injectors around 120,000 miles to justify the pop test?



Honestly, I'm very surprised how well the truck ran w/ all the carbon built-up. I wouldn't have suspected the injectors if it wasn't for the smoke.

Just kinda makes me think the overall condition is good and save the $60. 00.

Or am I being penny wise and pound foolish?

 

[TRCM]

I'd say just make sure you know what ya got before ya go replacing injectors. .



I just put in some DD2's to replace what I was told were stock injectors. but once I replaced them, I found out the truck had marine 300's in it... so I kinda stepped backwards.



Not sure what I am gonna do, but I know the very least will be to clean the ones I removed, and put them back in.



So I will most likely have a set of DD2's with less than 500 miles on them for sale shortly. expensive mistake.

 

[SteveAnsley]

I'm not planning on replacing the injectors.

I'd have them re-built if necessary.



I'm 99. 9% certain they are stock 215's.

This is whats on the body:

0325

KDAL 59P6 767

260 bar



I was planning on taking them in to be pop tested.

Now, I'm thinking about 'poor boying' it and putting back in - I've already cleaned them up.

After seeing how bad they looked and how relatively well the truck was running I'm thinking/hoping the injectors are in good shape.

Worst case is I'll have to take it all apart again.



We're trying to watch the funds pretty close right now - kids and some medical expenses.

I still want to get the gauges and if the pop test isn't necessary - that's another $75. 00 towards the gauges.

Even yesterday as I was working on the motor I was wishing I had the gauges so as to confirm or deny current fuel or boost pressures.

 

[WadePatton]

Pop-testing is good. I'll check a set every time I have them out.



Because the first set I checked (370's with about 100k on them) were shot. The drizzled and ****** all over with low pop pressures. Today's clean diesel does NOT provide enough lubrication by itself to prevent "premature" injection component wear.



This experience renewed my faith in fuel additives for lubricity, nebbermind the cetane.





And fresh built injectors were $63 each down here.