Author Topic: OM617 Injectors Should I test them or just replace them  (Read 293 times)

Mergyver

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Hey guys I am hoping for some advice.

I bought a 1979 300SD last year and have just recently put it on the road. the car had sat for approximately 8-10 years before I bought it. It has 93,000 miles on it.

Prior to putting it on the road I drained all the old diesel fuel, replaced filters and cleaned tank screen, ran a few cans of undiluted diesel purge through it, replaced engine mounts, adjusted valves, replaced oil and filters, replaced rotten fuel lines and resealed injectors, checked turbo and boost pressure, and a few gaskets to stop oil leaks.

While the car is running well I don't seem to get as much power as I thought there would be and I have an intermittent miss at idle (some times it idles rough most of the time it does not). I have run two tanks of fuel through it and I am getting about 25MPG for a mixture of city and highway(mostly city).

The fellow who originally purchased the car had the dealer install an extra fuel tank in it. The purpose of the tank was to allow him to drive from his home in the NYC area to his vacation home in St Petersburg FLA with out having to stop for fuel. Remember 1979 was the days of the fuel embargo and Odd/Even gas lines.

My goal this year is to attempt that trip and see if it is possible. Half the fun of owning these cars are the stories we purchase them with. If I can average around 30MPG on the highway I think I can do it.

So  here's the question; Should I bother testing 40 year old (93,000 miles) injectors that sat for around ten years? OR should I just  toss them and get a set of those Monarch injectors that Ken B raves about on his sight? Do new injectors need to be tested to make sure they are balanced? I just don't know if it is worth spending time and money on a tester.

I also am hoping the Monarchs help increase my MPG. What do you guys think? Anything else you think I should do like checking injector pump timing or adjusting ALDA?

As always your words of wisdom are appreciated.

 

 
1974 450SEL
1979 300SD
1989 560SL
2005 E320 CDI Recently deceased

Alec300SD

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Re: OM617 Injectors Should I test them or just replace them
« Reply #1 on: 03 March 2019, 11:54 AM »
Send your new nozzles and used injectors to Mark (forum member Greazzer) at https://dieselfuelinjector.guru/

He has rebuilt mutiple injector sets for me and  many others.
He does top notch work at a reasonable fee
« Last Edit: 03 March 2019, 08:30 PM by Alec300SD »
79 W116 300SD 'Stormcloud' new as of 10/22/2017
78 W116 300SD 'Desert Rose' new as of 01/26/2014
83 W126 300SD 'Rena 2.0' with engine from 82 W126 300SD Rena' (SOLD and crushed 11-20-2017)

Harv

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Re: OM617 Injectors Should I test them or just replace them
« Reply #2 on: 03 March 2019, 12:01 PM »
Yepp, the middle ground here is sending them out for a rebuild.
1980 300SD
1983 240D
2000 E55 AMG

Diesel 617

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Re: OM617 Injectors Should I test them or just replace them
« Reply #3 on: 03 March 2019, 01:33 PM »
Send your new nozzles amd used injectors to Mark (forum member Greazzer) at https://dieselfuelinjector.guru/

He has rebuilt mutiple unjector sets for me and  many others.
He does top notch work at a reasonable fee

This route 100%
1980 300SD Retired
1979 280SE Euro Spec Import Crank Windows and Cloth Seats


Inventory Price
1980 450SEL/SE 722.004 Trans 150kmi ($50)
1978-1980 300SD Trans 260k mi $50
-2 450 Pairs + 300SD pair bad boots Axles $25/45
-3.07 450/300SD Differential $30

Mergyver

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Re: OM617 Injectors Should I test them or just replace them
« Reply #4 on: 05 March 2019, 01:23 PM »
Thanks for the tip guys. I reached out to Mark and got the details. I will have him rebuild a set for me. Trying to decide if I should go with stock injectors or something like the Monarks. Does anyone have any recommendations?
1974 450SEL
1979 300SD
1989 560SL
2005 E320 CDI Recently deceased

Diesel 617

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1980 300SD Retired
1979 280SE Euro Spec Import Crank Windows and Cloth Seats


Inventory Price
1980 450SEL/SE 722.004 Trans 150kmi ($50)
1978-1980 300SD Trans 260k mi $50
-2 450 Pairs + 300SD pair bad boots Axles $25/45
-3.07 450/300SD Differential $30

OLDGOLD

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Re: OM617 Injectors Should I test them or just replace them
« Reply #6 on: 06 March 2019, 05:18 AM »
Monarks all the way! The engine sounds much smoother and there is no more "nailing" at low speeds. Just have your existing injectors rebuilt with Monark's, no need to replace the entire injector.

Mergyver

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Re: OM617 Injectors Should I test them or just replace them
« Reply #7 on: 12 March 2019, 10:21 PM »
Looks like Monarchs are the way to go. Thanks for the input.
1974 450SEL
1979 300SD
1989 560SL
2005 E320 CDI Recently deceased

Mergyver

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Re: OM617 Injectors Should I test them or just replace them
« Reply #8 on: 04 April 2019, 08:16 PM »
Hey guys, I just wanted to follow up with a final report on where I ended up with this.

I took your advice and contacted Mark Blevins at dieselfuelinjector.guru . He set me up with a set of rebuilt injectors using NOS #1930 nozzles, new washers return hose, plug, and over flow valve spring. He turned them around very quickly, did a nice job at a good price.

They have made a huge improvement in the way the engine starts and accelerates. I am very happy so far with his work.

I have put about 150 miles on them so far. I am really looking forward to seeing if they make any difference in the MPG. I will report back after a couple of fuel tank fill ups.

Regards
1974 450SEL
1979 300SD
1989 560SL
2005 E320 CDI Recently deceased