Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 02-02-2021, 08:06 PM
Registered User
 
Join Date: Jun 2015
Posts: 262
Rebuilt injectors not firing once installed? OM617

Hey guys...


Just rebuilt the injectors in my '83 300sd. It ran (very poorly) prior to doing this. The injectors got new nozzles and were balanced to 2000psi. Injectors function well on the test stand with a good spray pattern.


Installed them and have since ran 3 batteries dead trying to get it to fire.


I get a trickle of fuel out of the injector nuts when loose... but not the spray I was getting before. It's as if the injection pump is not building pressure.


It had the lines off for several days but stayed covered up.


I'm considering pulling the hard lines and elements out of the pump to see f they are sticking or something but I'm at a loss.


I know for a fact that it's got weak compression but I had it on the block heater for a few hours... engine warm... and it has fresh glow plugs. Its producing ZERO smoke from the tail pipe. It's as if it isn't getting any fuel at all to the cylinders.


Thoughts?

Reply With Quote
  #2  
Old 02-02-2021, 08:39 PM
Registered User
 
Join Date: Sep 2007
Location: Calgary Alberta Canada
Posts: 1,925
Did you manually prime your injectors?
__________________
92 e300d2.5t
01 e320
05 cdi
85 chev c10
Reply With Quote
  #3  
Old 02-02-2021, 08:41 PM
Registered User
 
Join Date: Jun 2015
Posts: 262
Update... so I'm not getting squat out of the injection pump now.

I had the stop lever tied off for several days. Could something internal to the pump be stuck in the stop position?

With the lines off the pump and cranking.. just a slight trickle out of the fittings on the pump.

For giggles, I pinched the return and cranked the engine. Within a few rotations, it build enough pressure to blow the return cap off of the #5 injector. I'd say the lift pump is producing decent enough pressure.

I pulled the #1 delivery valve. It was pretty nasty. Even with the delivery valve completely removed (not the holder, just the valve and spring)... just a trickle from the pump.

Soo... I'm at a loss. Ideas?

The injectors were pop tested and installed. Cracked the lines and cranked and cranked... nothing. No pressure from the feed lines... just a slow trickle.
Reply With Quote
  #4  
Old 02-02-2021, 09:06 PM
Diesel911's Avatar
Registered User
 
Join Date: Sep 2007
Location: Long Beach,CA
Posts: 51,244
You can take out the Delivery Valve but don't remove the 2 each `13mm nuts on each side of the delivery valve to pull out the elements. Turning the element changes the calibrated fuel setting and changing the number of shims under it changes the timing.

Try disconnecting the vacuum line from the Shutoff on the Fuel Injection Pump. The main color or the line is brown or brown with a blue strip; cant remember exactly which one.

When you us the manual shutoff it compresses a spring loaded plunger which telescopes up inside of they. They have been know to get rusty inside and the plunger stick up wards. Make sure the plunger comes all the way out.
__________________
84 300D, 82 Volvo 244Gl Diesel
Reply With Quote
  #5  
Old 02-02-2021, 09:12 PM
Registered User
 
Join Date: Jun 2015
Posts: 262
Quote:
Originally Posted by Diesel911 View Post
You can take out the Delivery Valve but don't remove the 2 each `13mm nuts on each side of the delivery valve to pull out the elements. Turning the element changes the calibrated fuel setting and changing the number of shims under it changes the timing.

Try disconnecting the vacuum line from the Shutoff on the Fuel Injection Pump. The main color or the line is brown or brown with a blue strip; cant remember exactly which one.

When you us the manual shutoff it compresses a spring loaded plunger which telescopes up inside of they. They have been know to get rusty inside and the plunger stick up wards. Make sure the plunger comes all the way out.



Where is that plunger located? That's the only thing that makes sense.
Reply With Quote
  #6  
Old 02-03-2021, 07:59 AM
t walgamuth's Avatar
dieselarchitect
 
Join Date: Apr 2005
Location: Lafayette Indiana
Posts: 38,632
It is called a primer i think. I'd look for something very simple like a plugged filter or as 911 says a stuck primer.
__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.
Reply With Quote
  #7  
Old 02-03-2021, 10:06 AM
Diesel911's Avatar
Registered User
 
Join Date: Sep 2007
Location: Long Beach,CA
Posts: 51,244
Quote:
Originally Posted by AcIdBuRn View Post
Where is that plunger located? That's the only thing that makes sense.
In the attached picture the hard to see yellow arrow points to the spring loaded plunger that is telescopes inside of the Idle Adjustment Screw.
Attached Thumbnails
Rebuilt injectors not firing once installed?  OM617-fuel-injection-pump.jpg  
__________________
84 300D, 82 Volvo 244Gl Diesel
Reply With Quote
  #8  
Old 02-03-2021, 06:26 PM
Registered User
 
Join Date: Jun 2015
Posts: 262
Quote:
Originally Posted by Diesel911 View Post
In the attached picture the hard to see yellow arrow points to the spring loaded plunger that is telescopes inside of the Idle Adjustment Screw.

I'll check the little pin. I'm pretty sure it wasn't stuck but I'll look again.


I've also heard that the rack could be stuck in the closed position.


I've got some digging to do.
Reply With Quote
  #9  
Old 02-04-2021, 01:28 AM
Banned
 
Join Date: Nov 2020
Posts: 188
Tap the side of the pump with a rubber or dead-blow mallet.
Reply With Quote
  #10  
Old 02-04-2021, 09:32 AM
Registered User
 
Join Date: Jun 2015
Posts: 262
I checked the pin and it is moving as it is supposed to. I'm leaning towards the rack being stuck.

I wont have time to mess with it until Saturday at this point. Who knows... maybe sitting for a few days with the stop lever in the resting position will let it free up since being in the stop position for a few days is what caused it.

IDK at this point.
Reply With Quote
  #11  
Old 02-04-2021, 02:29 PM
Diesel911's Avatar
Registered User
 
Join Date: Sep 2007
Location: Long Beach,CA
Posts: 51,244
Quote:
Originally Posted by AcIdBuRn View Post
I checked the pin and it is moving as it is supposed to. I'm leaning towards the rack being stuck.

I wont have time to mess with it until Saturday at this point. Who knows... maybe sitting for a few days with the stop lever in the resting position will let it free up since being in the stop position for a few days is what caused it.

IDK at this point.
You can access the Rack by removing the ADLA with the whole rectangular plate that it is attached to. Never done that but there is threads somewhere on that.

The other way to go is to remove the Vacuum Shutoff because it hooks onto the Rack. However, putting the Vacuum Shutoff in place wrong results in a runaway engine. So if you choose that route do some research on it.

I think you said the delivery valve was cruddy. What do you think was in it?

I am asking that because if the rack is sticking whatever crud is inside of the pump can be the rack is sticking.

If the rack is not sticking crud could be restricting the fuel Feed Holes in the Element Barrels. Or the Plunger could have gone up and the crud is holding them up and the springs are not bringing them back down.
__________________
84 300D, 82 Volvo 244Gl Diesel
Reply With Quote
  #12  
Old 02-04-2021, 03:23 PM
Registered User
 
Join Date: Jun 2015
Posts: 262
Quote:
Originally Posted by Diesel911 View Post
You can access the Rack by removing the ADLA with the whole rectangular plate that it is attached to. Never done that but there is threads somewhere on that.

The other way to go is to remove the Vacuum Shutoff because it hooks onto the Rack. However, putting the Vacuum Shutoff in place wrong results in a runaway engine. So if you choose that route do some research on it.

I think you said the delivery valve was cruddy. What do you think was in it?

I am asking that because if the rack is sticking whatever crud is inside of the pump can be the rack is sticking.

If the rack is not sticking crud could be restricting the fuel Feed Holes in the Element Barrels. Or the Plunger could have gone up and the crud is holding them up and the springs are not bringing them back down.



Looked to be old veggie. Just a brownish gunk. The pump was working fine and now all 5 ports are dead so I doubt its a blockage. Not impossible but unlikely.


I'll probably pull all of the delivery valves and clean them up a bit.



I'll look into pulling the ADLA and taking a peak inside this weekend.
Reply With Quote
  #13  
Old 02-04-2021, 09:56 PM
Diesel911's Avatar
Registered User
 
Join Date: Sep 2007
Location: Long Beach,CA
Posts: 51,244
Quote:
Originally Posted by AcIdBuRn View Post
Looked to be old veggie. Just a brownish gunk. The pump was working fine and now all 5 ports are dead so I doubt its a blockage. Not impossible but unlikely.


I'll probably pull all of the delivery valves and clean them up a bit.



I'll look into pulling the ADLA and taking a peak inside this weekend.
If the Delivery Valves are full of crap then the inside of the Pump must also have solidified crap in it or had water in it and rusted.

I am assuming thins is an MW Fuel Injection Pump. If it is an MW with the Delivery Valves out (the 2 pieces of the delivery valve are mated and to one side of the Delivery Valve Body keep them in order and separated from the other delivery valve). Rotate the Engine and see if the plungers down inside of the Element are moving up and down.

Attached picture: View of Rack on MW Fuel Injection Pump with ALDA Removed
Attached Thumbnails
Rebuilt injectors not firing once installed?  OM617-view-rack-mw-fuel-injection-pump-alda-removed.jpg  
__________________
84 300D, 82 Volvo 244Gl Diesel
Reply With Quote
  #14  
Old 02-05-2021, 01:05 AM
Registered User
 
Join Date: Oct 2012
Posts: 5,924
You started a second post where some members might not know of your first three page post.

At a minumin this pump would need a serious solvent soak.Acetone or laquar thinner. Other members have reported what comes out with the relief valve removed after the soaks. Sometimes is far from pretty. Think blobs of stuff.

In days gone by if the car had ran WVO before their purchase. You also do not want to put some of what might be in there through a set of new rebuilt injectors.

A few cans of a cleaner are nothing in my opinion as it takes some time to break down the accumulated junk deposits. I suspect they originate from animal fats in the WVO.

Boy am I negative tonite. Still there is also a reality. Most of us run from a WVO car. Usually the first job would be to totally clean out the fuel system. At least it sounds like the valves in the lift pump are not crudded up.

You may prevail and I hope you do. I just do not think it will be easy.Again I can be wrong. On a time basis I would clean out the fuel system. Then change that injection pump.If he system did not come back on line. I am also a guy that does not suggest changing out an injection pump easily.

You just pump the solvent in with the primer pump and let it sit. There is nothing in there the solvents can damage it seems. As nobody mentioned a leakage after the soaks. Sometimes it take a few soaks until what comes out of the relief valve port to look decent.

Your atf and diesel may have removed varnish from the elements as well. These are just guesses of course. Your earlier post indicates there may be an issue in the govenor section of the injection pump as well. That section is lubricated by engine oil. He could have been running polyermized oil. Far too many WVO users did no maintenance at all as it was not "free".
Reply With Quote
  #15  
Old 02-05-2021, 03:05 AM
Registered User
 
Join Date: Oct 2013
Location: New Zealand
Posts: 538
i wouldn't do anything until I verified that the fuel rack is moving freely.

__________________
1978 300D, 373,000km 617.912, 711.113 5 speed, 7.5mm superpump, HX30W turbo...many, many years in the making....
1977 280> 300D - 500,000km+ (to be sold...)
1984 240TD>300TD 121,000 miles, *gone*
1977 250 parts car
1988 Toyota Corona 2.0D *gone*
1975 FJ45>HJ45
1981 200>240D (to be sold...)
1999 Hyundai Lantra 1.6 *gone*
1980s Lansing Bagnall FOER 5.2 Forklift (the Mk2 engine hoist)
2001 Holden Rodeo 4JB1T 2WD

Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 08:08 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page