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Fuel injector Rebuilding/testing and TM and compression testing

Ford Mechanic

Active member
1,805
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Location
Edenton, NC
Not right off hand, I left the adapter with the pop tester when I left the Ford shop. I got the brake line and nuts from a local truck hardware shop that makes our hydro hoses.
 

Katahdin

Active member
1,303
24
38
Location
Scarborough, ME
The diesel shop that tested my injectors called to say they were sticking and offered to clean them for $48 each. Nuts, at that price I might as well learn to clean them myself and buy an Indian pop tester. :shrugs:
 

TMNT

New member
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Location
Canton, Ga
I wouldn't pay $48 each to clean them. That's normally $20-$25 bucks to clean, test and set them. $48 sounds like a rebuild.

New injectors are $70.
 

Katahdin

Active member
1,303
24
38
Location
Scarborough, ME
The shop emailed me these pictures and a more detailed quote. Note for pressure they are not using the TM spec of 2800psi (193 bar). Is $48 a high price considering they would be dismantling the injector for cleaning and not just running a solvent through it?


Attached is pictures of injector
- low pressure @ 223 bar (should be 248-259 bar)
- sticky, bad spray pattern
- rust & old fuel (pressure adjusting screw, nozzle, etc)

$10 each to test & advise
Waive test fee if serviced –

- service holder $30. Each (1.60 each for shop supplies, ect.)
- service nozzle $15. Each – or cost of new nozzle
NBM770138 new ambac nozzle $80. each usually comes with nozzle gasket
- GA79148 s/s GA404115 adapter gasket $1.62 ea – need to order -



Picture0225161001_1.jpgPicture0225161002_1.jpgPicture0225161003_1.jpg
 

TMNT

New member
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Location
Canton, Ga
They're doing a rebuild. $48 for that doesn't look bad to me, but my experience with these injectors is limited.

If they are replacing the springs, then the 248-259 bar pop pressure is a little high, but close. That's about 3600-3750 psi. The info I found said new springs should be set at 3,400 psi (234 bar).

2800 psi (193 bar) is supposedly what the springs settle down to after breaking in. The book says the new springs "take a set" to 2,800.

I would be hesitant to set used springs to 3,700 psi pop. That's too much pressure on the injection pump. (My opinion based on the TM.)

At least yours are getting worked on. Mine are still sitting on the shelf at the shop. We still don't have a solution to connect the injectors to the pop tester.
 

rustystud

Well-known member
9,266
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Location
Woodinville, Washington
They're doing a rebuild. $48 for that doesn't look bad to me, but my experience with these injectors is limited.

If they are replacing the springs, then the 248-259 bar pop pressure is a little high, but close. That's about 3600-3750 psi. The info I found said new springs should be set at 3,400 psi (234 bar).

2800 psi (193 bar) is supposedly what the springs settle down to after breaking in. The book says the new springs "take a set" to 2,800.

I would be hesitant to set used springs to 3,700 psi pop. That's too much pressure on the injection pump. (My opinion based on the TM.)

At least yours are getting worked on. Mine are still sitting on the shelf at the shop. We still don't have a solution to connect the injectors to the pop tester.
I agree about the spring settings also. Used springs need to be set at 2800 psi. They are charging a little higher then normal amount for basically a good cleaning and setting of the pressure. This is in no way a rebuild though. A rebuild would have new springs and nozzles and pins installed. I've never seen anyone break down the cleaning to clean holder and clean nozzle. It is a unit, a whole thing. Not pieces of a working device, but an integral working device itself. So when they say they will clean your injectors, they clean all of it. So $48.00 is a higher then normal price for injector cleaning.
 

TMNT

New member
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Location
Canton, Ga
I finally had to give up on my local shop and I picked up my injectors today. AMBAC says they'll "test them for function" for $48 each, plus shipping both ways. Other services to be quoted after testing. Ain't doing that.

I might end up shipping them to Portland. If I had more free time, I'd figure out how to build a pop tester. Working 80+ hours a week doesn't leave much play time.
 

rustystud

Well-known member
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Location
Woodinville, Washington
I got a dumb question how do you adjust and set the pressure. I'm just curious being I never seen anyone say how
Depends which style of injectors you have. One takes "shims" to adjust the spring tension. The other has an adjustable screw to put pressure on the spring. Of course everyone loves the adjustable screw one. The shims can be hard to come by. "Ford Mechanic" had some A/C shims that worked OK. You can ask him what they come on and where he got them.
 

TMNT

New member
789
6
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Location
Canton, Ga
I've been doing some measuring and some studying this evening. I'm 95% certain that he injector connection is an 1/2" x 20 male tube nut for 1/4" tubing. The hard part seems to be the 1/2 x 20 is usually fitted to 5/16" line.

(The connection at the injection pump seems to be a 9/16 x 18 male tube nut.)

The tubing is 1/4" OD steel.

I ordered a $200 pop tester that looks like it might come with the correct adapter. If I need to, I'm confident that I can get a local brake shop to make up a line for me.

The pop tester should be here by Thursday. I have to be out of town through the weekend, so it may be another week before I can get back on this.

It looked like I was going to spend at least a couple of hundred bucks on getting the injectors tested and set, so I decided to invest in the tools. If all this works out successfully, I'll bring the tester to the Georgia Rally in October.
 
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Katahdin

Active member
1,303
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38
Location
Scarborough, ME
I'm interested in how your pop tester works out.

On my end, I thought I had worked out a compromise to save a little money. You see, I had a set of new injector nozzles purchased here on a SS group buy a few years ago and the injector shop said they would knock $15 off the service price if they used my new nozzles. Sounded like a good idea so I went with it.

Well, the shop just emailed me. The nozzles I bought on the SS group buy do not fit my injectors. Go figure!
INV 14434.jpg

My injectors are the newer type, my best guess is the nozzles I bought on the group buy fit the older (shim) style injector.

Oh well, at this point I'm just going to pay the extra money for the service. This shop has serviced multifuel injectors before so I know what they are doing. One well-known place to buy military trucks in Maine is Schott's in Lewiston. Schotts uses this same shop to service their injectors. When I do this again for my second deuce however, I'd like to try the work myself now that I have a little more knowledge about the process.
 
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TMNT

New member
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Location
Canton, Ga
I'm anxious for it to get here. It should arrive tomorrow but I'm leaving about noon for a few days. I'll test it out as early next week as possible. I'm so ready to get that done and get my truck going again!
 

rustystud

Well-known member
9,266
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Location
Woodinville, Washington
I'm interested in how your pop tester works out.

On my end, I thought I had worked out a compromise to save a little money. You see, I had a set of new injector nozzles purchased here on a SS group buy a few years ago and the injector shop said they would knock $15 off the service price if they used my new nozzles. Sounded like a good idea so I went with it.

Well, the shop just emailed me. The nozzles I bought on the SS group buy do not fit my injectors. Go figure!
View attachment 611419

My injectors are the newer type, my best guess is the nozzles I bought on the group buy fit the older (shim) style injector.

Oh well, at this point I'm just going to pay the extra money for the service. This shop has serviced multifuel injectors before so I know what they are doing. One well-known place to buy military trucks in Maine is Schott's in Lewiston. Schotts uses this same shop to service their injectors. When I do this again for my second deuce however, I'd like to try the work myself now that I have a little more knowledge about the process.
That's good to know about the injector nozzles. Bad for you of course.
 

The Stig

Member
69
2
6
Location
North GA.
Does anyone know of an Atlanta area shop that can pop-test these AMBAC injectors?
What shop were you talking to? I was looking to go to Turbo Diesel and Electric systems 4923 Canton Road Marietta, GA 30066 (770)424-0330, wasn't sure if you had spoken with them. I believe their shop in Forest Park rebuilt the IP in my truck before I got it. So I thought I might try the canton shop just in case. if nothing else maybe they would be willing to ship things between their shops for me. If its even possible for them to do the work. But their site says they service and repair [FONT=Verdana, Helvetica, sans-serif]AMBAC/Bosch so I wasn't sure if you had spoken with them.[/FONT]
 

TMNT

New member
789
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Location
Canton, Ga
What shop were you talking to? I was looking to go to Turbo Diesel and Electric systems 4923 Canton Road Marietta, GA 30066 (770)424-0330, wasn't sure if you had spoken with them. I believe their shop in Forest Park rebuilt the IP in my truck before I got it. So I thought I might try the canton shop just in case. if nothing else maybe they would be willing to ship things between their shops for me. If its even possible for them to do the work. But their site says they service and repair [FONT=Verdana, Helvetica, sans-serif]AMBAC/Bosch so I wasn't sure if you had spoken with them.[/FONT]
That's the one. Real nice people and they seem to do a lot of diesel work. My father-in-law uses them for his dump trucks and heavy equipment. He just couldn't figure out how to connect the deuce injectors to his pop tester.
 

TMNT

New member
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6
0
Location
Canton, Ga
The pop tester that I ordered from that popular auction site, still hasn't arrived. UPS was showing "order received for processing" but no shipping info. Now it says "shipping voided." I've contacted the 5-star vendor and they say their checking on it. Hopefully we get it resolved quickly.
 

TMNT

New member
789
6
0
Location
Canton, Ga
I'm seriously beginning to think injector pop testers are made of unobtainium!

The first one I ordered got lost before it ever shipped and it was the last one the seller had. Something entirely hinkey about that whole deal.

I got my money back and ordered one from a different vendor. This one showed as "shipped" by US Postal Service, from Canada. The vendor's tracking site said delivery on the 18th, and the USPS system said the 17th.

Here I sit on the 20th with no pop tester. The vendor's system says "it's almost there!" while the postal service says it is delayed in Atlanta.

Meanwhile, my deuce sits in the driveway and my injectors are sitting on the workbench in my garage.
 

TMNT

New member
789
6
0
Location
Canton, Ga
Pop tester arrived yesterday. Sort of.

The packaging consisted of basically dropping a 24 pound piece of steel in a box. By the time the package reach Atlanta, the box was a wreck. USPS took the whole mess, and put it inside another box, and then delivered it.

I checked it out last night and aside from a missing pump handle, it's all ok. I still need to have a steel line built to go from the M14x1.5 flare on the pump, to the 1/2 x 20 inverted flare tube nut for the injector.

Not there yet, but one step closer!
 

Wildchild467

Well-known member
Steel Soldiers Supporter
2,052
57
48
Location
Milford / Michigan
That's the one. Real nice people and they seem to do a lot of diesel work. My father-in-law uses them for his dump trucks and heavy equipment. He just couldn't figure out how to connect the deuce injectors to his pop tester.
I gave my hydraulic hose shop a piece of injector line from a deuce which they cut and spliced that to a hose. I told them it could be around 3600 PSI and then they worked their magic on the connection to the pop tester.
 
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