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D4D Injector removal & Glow Plug replacement

Metalman 55

Metalman 55

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On my D4D #78A5667 tractor we tried pulling all the glow plugs to see what condition they were in. Two came out ok & two did not (one of the ones that came out had a crack on the electrode end). One of the stubborn ones came out part way & then the tread started binding, so we ran it back in. Put tester on & they all draw around 4.5 amps on 24volts.

I see that the one appears to have a number on it, which looks to be "A73" (not sure of the number). I would like to check into getting a new set seeing that one had a crack in it. Anyone know if that may be a good number & who makes it if in fact it is available through aftermarket? It is the original motor in the unit as the same ser# in on the engine block.

Also, we need to pull the injectors to get at the stubborn glow plugs. Does anyone know how to identify the special socket or tool that turns out the injector body? My parts book does not show that style of injector body. See the attached photos.






Glow Plug.jpgInjector.jpg
 
Coaldust

Coaldust

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D4

I believe you will need a Cat 5F-8353 tool for removing the pre-cumbustion chamber. Remember to drain the coolant and order new pre-cup "O"-rings and gasket. The pre-cups can be stuck in place and hard to remove. Good luck,

Coaldust

image.jpg
 
AllDodge

AllDodge

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Well SIS is a bit strange on your serial number, it says there are no 78A prefix numbers. I can find the prefix on iron planet but not at CAT go figure. I used a 74U prefix for a later model D4D and found the following info. Older glow plug number is 1P-7324 and newer one is 4N-0360. Now my 955L uses the same 1P-7324 glow plugs. They were real easy to remove/replace, just put a socket on them and unscrewed them. Found some on ebay a few years ago for dirt cheap. It came with 6 in the bunch so I wound up with two extras.

Hope this helps

Edit: I did soak them over night in PB blaster
 
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old-iron-habit

old-iron-habit

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I believe 78A is a machine assembled and sold outside of the US. There was a post the other day on the ACMOC bulletin board with charts attached converting the numbers to US equals. There is also several posts discussing how to make a tool and about removing stubborn injectors.

Hope this help you.
 
O

Old Magnet

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The D4D 78A series is a USA built machine from 1963 to 1968. 78A5667 is a 1966 built model.
The original pre-combustion chambers were part #9H5888 RPB #2S9793.
The original glow plugs were part #4S7824 = #1P7324 = #3T9562 and several others.
5F8353 is the correct chamber removal tool.
4.5 to 5 amps per glow plug is about right.
 
Metalman 55

Metalman 55

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Old Magnet said:
The D4D 78A series is a USA built machine from 1963 to 1968. 78A5667 is a 1966 built model.
The original pre-combustion chambers were part #9H5888 RPB #2S9793.
The original glow plugs were part #4S7824 = #1P7324 = #3T9562 and several others.
5F8353 is the correct chamber removal tool.
4.5 to 5 amps per glow plug is about right.
Click to expand...

Ritchie Wiki says the 78A's were US manufactured as well.

Thanks for sending the information re the various parts & numbers. I have emailed our local Cat dealer & will see what they come back with.
 
Metalman 55

Metalman 55

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AllDodge said:
Well SIS is a bit strange on your serial number, it says there are no 78A prefix numbers. I can find the prefix on iron planet but not at CAT go figure. I used a 74U prefix for a later model D4D and found the following info. Older glow plug number is 1P-7324 and newer one is 4N-0360. Now my 955L uses the same 1P-7324 glow plugs. They were real easy to remove/replace, just put a socket on them and unscrewed them. Found some on ebay a few years ago for dirt cheap. It came with 6 in the bunch so I wound up with two extras.

Hope this helps

Edit: I did soak them over night in PB blaster
Click to expand...

As mentioned on my post, 2 glow plugs came out, one would not move (we were afraid of breaking it) & one threaded out part way & the threads started to bind up. We tried a lubricant, going back & forth etc. but it would not come, so we threaded it back in as far as it would go & left it for now. Hope to get the removal tool & then go back at it.
 
O

Old Magnet

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Not unusual to have the glow plugs stick or break off in the chambers. They are a stepped diameter affair that makes it pretty difficult to remove the broken ones. Probably best just to replace both the glow plug and chamber.
Be sure to use plenty of anti-seize when replacing both.
 
Metalman 55

Metalman 55

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I got the #5F8353 extraction tool in, expecting that it would fit over the external portion of the injector housing but it is different. It looks the same as the photo that Coaldust put up, but I had thought it may have the right size spline on the inside of the hex...not the case. We have not taken things apart yet.....maybe this smaller spline fits the inside of the body somehow?5F8353.jpg
 
L

lantraxco

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Yup, remove the fuel line, remove the threaded adapter, the body is splined down inside. Never made sense to me, but that's the way Cat did it.
 
O

Old Magnet

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I can't tell for sure from your picture but I think I see a splined retaining nut. That is not the normal D4D setup. It's what was used on the regular D4 and requires a splined socket part #8S2243 for removal plus the D4 used a 3H2033 glow plug. Should be a part number on the glow plug or I have dimensions for the D4 unit to check.
The 3H2033 glow plug has 5/16 threaded section, the D4D unit should be 3/8 thread.
 
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Metalman 55

Metalman 55

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Holland Injector.jpg

Old Magnet, I just went out & took this photo on another D4D Parts machine I have (#78A6909) & the injector setup looks the same on the 2nd machine. Are you saying that outer spline appearing in the photo is how the body is removed? If so, my tool that I just picked up is wrong? My glow plugs have 3/8" #24 thread on them.
 
O

Old Magnet

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To remove the injector you first have to remove the retaining nut which is an exterior spline that you see and takes the internal splined thin wall socket to remove it. Once the retaining nut is removed you can remove the body and injector nozzle which gives you access to the internal spline in the pre-combustion chamber where the tool you have is used for removal.
 
Metalman 55

Metalman 55

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Old Magnet said:
To remove the injector you first have to remove the retaining nut which is an exterior spline that you see and takes the internal splined thin wall socket to remove it. Once the retaining nut is removed you can remove the body and injector nozzle which gives you access to the internal spline in the pre-combustion chamber where the tool you have is used for removal.
Click to expand...

So is #8S2243 the correct socket to remove the exterior spline shown in my last picture?
 
B

Birken Vogt

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Is it too late to suggest that they be left alone. If they are drawing 4.5 amps then they are working. That power is making them get hot and that is what you want. What is the symptom you are having?
 
Metalman 55

Metalman 55

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Birken Vogt said:
Is it too late to suggest that they be left alone. If they are drawing 4.5 amps then they are working. That power is making them get hot and that is what you want. What is the symptom you are having?
Click to expand...

One of the glow plugs that came out (2 refused) had a crack near the bottom, so thought it may be good to replace them. I have the new ones now. Also when the machine starts cold it has a miss for quite a while & eventually once warm, it will hit on all four & smooth out. I understand if we can get the injectors out, we can have them bench tested for performance & go from there.
 
GregsHD

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I have seen these precups in 3304's and 3306, remove the injector line, remove the nut at the top of the precup, remove the nozzle, slide your removal tool in the hole and hope the last guy put neverseize on the threads!! New o-rings, new glow plugs, new nozzles and lots of neverseize, shouldn't have any headaches for a long time!
 
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