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Cat 3116 engine injectors syncing

Mobiltech

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Yes but hard to say convey to someone if they’ve never worked on one before. Have you ever done one with the tools?
It’s the engine assembled and runs or are you putting in injectors with rockers removed?
 
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Aaron.ampcon

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Yes but hard to say convey to someone if they’ve never worked on one before. Have you ever done one with the tools?
It’s the engine assembled and runs or are you putting in injectors with rockers removed?
I have never done it with the tools but I understand the principle and understand how I can set the injector height using a caliper but I'm not to sure about how to go about doing the syncing and setting the fuel. The engine is assembled and running but it smokes alot.
 

Mobiltech

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Synch will not get rid of grey smoke. Seats should be reamed if necessary but you’ll need the proper tool.
To answer your question the injectors don’t need a special tool to install after reaming.
Did you install a small o ring near the tip of the injector? That seal can give you a temporary seal to stop seat leakage which would let you know if reaming is required. Air leak at seat will cause hard start and smoke.
Are you sure the timing dimension was set properly because that will cause smoke too
 

Tenwheeler

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I have never done it with the tools but I understand the principle and understand how I can set the injector height using a caliper but I'm not to sure about how to go about doing the syncing and setting the fuel. The engine is assembled and running but it smokes alot.
What was done to this engine and why? They were prone to crack an injector sleeve.
Others mentioned reaming sleeves. I have done that with new sleeves but can that be needed while just replacing injectors?
Setting the rack is possible without factory tools but I am reluctant to comment. I has been a long time.
Make sure you have no air in the fuel inlet line to the head.
 

Aaron.ampcon

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Mar 19, 2020
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116
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Ghana
Synch will not get rid of grey smoke. Seats should be reamed if necessary but you’ll need the proper tool.
To answer your question the injectors don’t need a special tool to install after reaming.
Did you install a small o ring near the tip of the injector? That seal can give you a temporary seal to stop seat leakage which would let you know if reaming is required. Air leak at seat will cause hard start and smoke.
Are you sure the timing dimension was set properly because that will cause smoke too
I was thinking about trying the small o ring at the tip but didnt know if it would have been a problem. When you say timing dimension do you mean injector height?
 

Aaron.ampcon

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Mar 19, 2020
Messages
116
Location
Ghana
What was done to this engine and why? They were prone to crack an injector sleeve.
Others mentioned reaming sleeves. I have done that with new sleeves but can that be needed while just replacing injectors?
Setting the rack is possible without factory tools but I am reluctant to comment. I has been a long time.
Make sure you have no air in the fuel inlet line to the head.
The engine was rebuilt with new rings and stuff and then new injectors installed in an attempt to resolve tbe tons of smoke issue, if there was an injector cup crack wouldnt there be fuel in the coolant or vice versa?
 

Cmark

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A few notes on these things regarding the sleeves and reaming/seating thing.

The injector sleeves on these engines are made from a softish copper alloy material. In the early days, new sleeves had the tapered seat cut (reamed) with a special tapered cutter, much along the lines of a valve seat cutter. The injectors were then installed and that was that - until - they would start to leak cylinder gases past the taper and into the fuel gallery. The remedy was to remove the injector(s) and recut the seat. It was a finicky procedure that required good condition tooling and an experienced mechanic for any king of success. Even then success maybe ran around 50/50 long term as the sleeves became work hardened.

Then arrived the "seating tool". This is a bridge affair that goes over the top of the injector and pushes the injector hard down into the copper sleeve creating a more reliable seal. I recall Cat called it "coining"? Although cutting the seats was still officially required, the coining was a huge improvement and the success of repair increased enormously.

In time, the mechanics realised that the coining was kind of making the reaming redundant and so, among the more independent-minded of us, the standard MO for leaking seats was (is) to install a new set of sleeves, forget about the reaming and install the injectors with the coining tooling. This pretty much ensures long term success.
 

Aaron.ampcon

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Joined
Mar 19, 2020
Messages
116
Location
Ghana
A few notes on these things regarding the sleeves and reaming/seating thing.

The injector sleeves on these engines are made from a softish copper alloy material. In the early days, new sleeves had the tapered seat cut (reamed) with a special tapered cutter, much along the lines of a valve seat cutter. The injectors were then installed and that was that - until - they would start to leak cylinder gases past the taper and into the fuel gallery. The remedy was to remove the injector(s) and recut the seat. It was a finicky procedure that required good condition tooling and an experienced mechanic for any king of success. Even then success maybe ran around 50/50 long term as the sleeves became work hardened.

Then arrived the "seating tool". This is a bridge affair that goes over the top of the injector and pushes the injector hard down into the copper sleeve creating a more reliable seal. I recall Cat called it "coining"? Although cutting the seats was still officially required, the coining was a huge improvement and the success of repair increased enormously.

In time, the mechanics realised that the coining was kind of making the reaming redundant and so, among the more independent-minded of us, the standard MO for leaking seats was (is) to install a new set of sleeves, forget about the reaming and install the injectors with the coining tooling. This pretty much ensures long term success.
Thank you for this info!
 

Mobiltech

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Would you be able to post a video or pictures of the engine and smoke while running. With a 3116 it’s tough to point out one thing without hearing or seeing what it’s doing.
You could also put a clear plastic line on the return fuel lin3 and check for bubbles.
If a cup is cracked you would have fuel in the coolant.
I seat the injector without the seating tool but you have to be careful doing it. The tool is better
When you say new rings installed did you check cylinder bore wear or just rering?
 
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Nige

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G..G..G..Granville.........!! Fetch your cloth.
Would you be able to post a video or pictures of the engine and smoke while running. With a 3116 it’s tough to point out one thing without hearing or seeing what it’s doing.
For the benefit of the new member the best way seems to be to upload a video to YouTube then post a link to it here. HEF does not permit the direct uploading of videos.
 

Tenwheeler

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Joined
Dec 15, 2016
Messages
870
Location
Georgia
A few notes on these things regarding the sleeves and reaming/seating thing.

The injector sleeves on these engines are made from a softish copper alloy material. In the early days, new sleeves had the tapered seat cut (reamed) with a special tapered cutter, much along the lines of a valve seat cutter. The injectors were then installed and that was that - until - they would start to leak cylinder gases past the taper and into the fuel gallery. The remedy was to remove the injector(s) and recut the seat. It was a finicky procedure that required good condition tooling and an experienced mechanic for any king of success. Even then success maybe ran around 50/50 long term as the sleeves became work hardened.

Then arrived the "seating tool". This is a bridge affair that goes over the top of the injector and pushes the injector hard down into the copper sleeve creating a more reliable seal. I recall Cat called it "coining"? Although cutting the seats was still officially required, the coining was a huge improvement and the success of repair increased enormously.

In time, the mechanics realised that the coining was kind of making the reaming redundant and so, among the more independent-minded of us, the standard MO for leaking seats was (is) to install a new set of sleeves, forget about the reaming and install the injectors with the coining tooling. This pretty much ensures long term success.
A few notes on these things regarding the sleeves and reaming/seating thing.

The injector sleeves on these engines are made from a softish copper alloy material. In the early days, new sleeves had the tapered seat cut (reamed) with a special tapered cutter, much along the lines of a valve seat cutter. The injectors were then installed and that was that - until - they would start to leak cylinder gases past the taper and into the fuel gallery. The remedy was to remove the injector(s) and recut the seat. It was a finicky procedure that required good condition tooling and an experienced mechanic for any king of success. Even then success maybe ran around 50/50 long term as the sleeves became work hardened.

Then arrived the "seating tool". This is a bridge affair that goes over the top of the injector and pushes the injector hard down into the copper sleeve creating a more reliable seal. I recall Cat called it "coining"? Although cutting the seats was still officially required, the coining was a huge improvement and the success of repair increased enormously.

In time, the mechanics realised that the coining was kind of making the reaming redundant and so, among the more independent-minded of us, the standard MO for leaking seats was (is) to install a new set of sleeves, forget about the reaming and install the injectors with the coining tooling. This pretty much ensures long term success.
Thank you and the others with experience on these. Some done around here may have been cracked and it sounds like others likely just had a bad seat. We pulled the head. Replaced and cut all the new sleeves. Sometimes replaced rings, bearings and a valve job. Then they worked for a long time. Just doing one caused us to go back again. Never heard of the coining. Thanks for the education, hope I don't need to use it.
 

Cmark

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Jan 2, 2009
Messages
3,178
Location
Australia
Part number for the seating tooling is 1731530 if anybody is interested. Costs about $750 here in godzone so probably about $500 in the US of A
 

Aaron.ampcon

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Mar 19, 2020
Messages
116
Location
Ghana
Thanks guys for everything but corona is shutting down everything in my country so dont know when I would be able to get back on the 3116 :(
 
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