TCM IO-520-D fuel nozzles

Tom-D

Tom-D

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Tom-D
TCM service Bulletin:
http://www.tcmlink.com/pdf2/SB06-1A.pdf

I removed and cleaned the 6 injector nozzles in the 520, all nozzles are P/N D13A this is the old type of unbalanced nozzle that allows the EGTs to peak and different temps.

My customer wants the later style What is the proper Number?
 
Checkout_my_Six said:
call GAMI....and get their STC.
Click to expand...

The TCM stock injectors are calibrated just like GAMIs and half the cost.

Last couple days I've taken a big lesson on TCM fuel injection.

The service bulletin above does not give the P/N for the IO-520-D it does tell us the TSIO version, they state that the first digit is the cylinder number that it is meant to be installed in.
 
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Tom-D said:
My customer wants the later style What is the proper Number?
Click to expand...

For an IO-520D-40B (your suffix might be different--look at the data plate and get back to us) the injectors, for cylinders one thru six respectively, are:
655234-1250
655234-2250
655234-3250
655234-4250
655234-5250
655234-6250

Dan
 
Dan Thomas said:
For an IO-520D-40B (your suffix might be different--look at the data plate and get back to us) the injectors, for cylinders one thru six respectively, are:
655234-1250
655234-2250
655234-3250
655234-4250
655234-5250
655234-6250

Dan
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thank you, that is a different number than we could find in the IPB or SBs. I'll call the order in today.
 
Just got off the phone with TCM parts.

The P/N for the whole set is 655234-A13, price (my cost), 569.51, that gives us the 6 injectors that are calibrated for the IO-520-D. same as GAMI. with no STC required for installing a superseded P/N by the manufacturer.. = no STC required.
This kit contains the 6 part number you gave me.
 
Next question,,,

How to determine the proper leaning technique, and stay with in TCM's guidelines.
This engine was bought new in 2004 and has about 650 TT. runs great. we'd like to keep it that way.
 
Make sure the fuel flow is set at the high end.....+29 gph or more. Those cylinders will thank you.

btw....I'm running the red-headed sister to that.....the TSIO-520D :D
 
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Checkout_my_Six said:
Make sure the fuel flow is set at the high end.....+29 gph or more. Those cylinders will thank you.

btw....I'm running the red-headed sister to that.....the TSIO-520D :D
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That is not what TCM recommends for the IO- the guy at Technical tells me the 1000RPM mixture check should stay the same. run 2-3 minutes at 1500 RPM reduce RPM to 1000 RPM and slowly pull the mixture out and watch for a rise of no more than 50 RPM but no less than a perceptible rise.
 
Tom....that was full power fuel flow. Not idle. And yes, there should be a rise at shut down.:rolleyes2:
 
Checkout_my_Six said:
Tom....that was full power fuel flow.
Click to expand...

I do not know that.

The whole story, I am doing the annual. so I notice the injectors were never cleaned since new. So I remove them and soak them over night in Hoppys #9. clean them and replace, they were all P/N D13A that was the only number on them.
We ran the engine after annual, (as required) and the owner thought it run rough at idle.
Then I call TCM tech, and ask what could cause this, they say I probably mixed up the injectors and have the wrong ones in the cylinders. I tell them that the injectors are all the same P/N, how could they be mixed up? and add the engine came that way from the factory. That's when they say try the idle mixture check, I did no rise, so I tweeted the mixture of the Fuel control 1/4 turn rich, that cured the rough idle.

But now the owner wants to update the nozzles.
 
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Checkout_my_Six said:
sorry Tom....If you can get +29 gph at idle, you'd be my hero. :D
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In your TSIO, that may be proper, in the IO, I don't know.

The Injection test gauges and mm are on the way.

But he is flying it this week. as it was equipped for the last 650 hours.
 
Tom....there are idle settings....and full power fuel flow (pump) settings. Sorry for the confusion, but I was referring to the full power settings.

There is a CMI SB that calls all this out......and the max fuel flow settings for the IO-520D is +26 GPH.
 
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Checkout_my_Six said:
Tom....there are idle settings....and full power fuel flow (pump) settings. Sorry for the confusion, but I was referring to the full power settings.

There is a CMI SB that calls all this out......and the max fuel flow settings for the IO-520D is +26 GPH.
Click to expand...

My discrepancy was at Idle. why should I change any thing on the full power side ? 1/4 turn rich fixed it.
 
Tom-D said:
My discrepancy was at Idle. why should I change any thing on the full power side ? 1/4 turn rich fixed it.
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Because pump pressure setting will also affect idle. I was taught to set max pressure (fake flow) first, then set the idle after that.
 
Henning said:
Because pump pressure setting will also affect idle. I was taught to set max pressure (fake flow) first, then set the idle after that.
Click to expand...

Doesn't matter what you were taught, I'll go with TCM tech. and what the Manual says to do.
 
Checkout_my_Six said:
There is a CMI SB that calls all this out.....
Click to expand...

I think we are on version F now (SID97-3F)
here's a copy
the last three versions may not affect this discussion, but it's always nice to have the latest.

They warn against tweaking just one adjustment as it could affect the other parameters, this is my experience when I set mine up.

"Adjustments to any component of the fuel injection system can affect other system settings. Always verify the performance of the entire fuel injection system whenever any fuel injection system component is adjusted."
 
Let'sgoflying! said:
I think we are on version F now (SID97-3F)
here's a copy
the last three versions may not affect this discussion, but it's always nice to have the latest.

They warn against tweaking just one adjustment as it could affect the other parameters, this is my experience when I set mine up.

"Adjustments to any component of the fuel injection system can affect other system settings. Always verify the performance of the entire fuel injection system whenever any fuel injection system component is adjusted."
Click to expand...

Exactly, when you adjust FI, you start with the pressure because everything bases off of that. If the pump loses pressure, everything leans. When you compensate on the enrichment, you don't solve the problem, just one of the symptoms. It's like making up for points wear by tweaking the magneto housing to get the timing back. You cover up one symptom, but create problems elsewhere.
 
The adjustment procedures provided in this document also apply to engine fuel systems equipped with CMI Position Tuned Fuel Nozzles. Refer to Publication Number FI-2, Position Tuned Fuel Injector Nozzle Installation and Maintenance Manual for more detailed information and installation instructions.

And who assumed the fuel pressures weren't checked?

Just because I did not specifically say I did them doesn't mean I didn't.
The pubs and my own test equipment has been shipped.
And we will follow them to the letter.
 
Henning said:
Exactly, when you adjust FI, you start with the pressure because everything bases off of that.
Click to expand...

That's not what the service letter says. that doesn't happen until steps 13-15. then the step 16 says that when every thing is correct go to step 24. this engine failed to rise when the mixture was moved to idle cutoff, we corrected that and that fixed the aircraft all other pressures were spot on.
 
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Tom-D said:
That's not what the service letter says. that doesn't happen until steps 13-15. then the step 16 says that when every thing is correct go to step 24. this engine failed to rise when the mixture was moved to idle cutoff, we corrected that and that fixed the aircraft all other pressures were spot on.
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Setting from scratch you need rough mix so you don't burn the engine up going full power and setting pressure, then you go back and reset mixture again to the new pressure. If you are dealing with a change in how it runs after you just cleaned the nozzles, you probably affected the system pressure and need to check it.
 
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Henning said:
Setting from scratch you need rough mix so you don't burn the engine up going full power and setting pressure, then you go back and reset mixture again to the new pressure. If you are dealing with a change in how it runs after you just cleaned the nozzles, you probably affected the system pressure and need to check it.
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And when the pressures are correct, what then.

A. you fix the discrepancy.
 
Tom-D said:
And when the pressures are correct, what then.

A. you fix the discrepancy.
Click to expand...

Right, but you start by knowing the pressures are correct. If the nozzles were never serviced and clogged, there's a good chance someone addressed a high pressure squawk by turning down the pressure rather than cleaning the nozzles.
 
Henning said:
Right, but you start by knowing the pressures are correct. If the nozzles were never serviced and clogged, there's a good chance someone addressed a high pressure squawk by turning down the pressure rather than cleaning the nozzles.
Click to expand...

What makes you think we did not check the pump out put first? then find the lean idle mixture? (no drop)

Please read, we did it by the book IAW the tech from TCM, which may or my not be your way.
 
Your customers would be better off with Gamijectors, which GAMI will "tweak" after sale.

The TCM injectors are junk, can't be "tweaked," and just a knee jerk reaction to GAMI.
 
kgruber said:
Your customers would be better off with Gamijectors, which GAMI will "tweak" after sale.

The TCM injectors are junk, can't be "tweaked," and just a knee jerk reaction to GAMI.
Click to expand...

Got a reference for that ? something I can show the owner?
 
Tom-D said:
Members only.
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It's a free site. Sign up! You'd enjoy it!!

But it is a fact that not all IO-520D are exactly set up the same. There are variances in the cylinders. Just because TCM sells (they had to as their good customers were beating them up) "balanced" injectors, doesn't mean ALL the cylinders will balance correctly. And TCM will not "tweak" them to make the fuel flow balance.

Gami will. Install a set, do the GAMI test, and if the FFs are more than .2g/hr off they will send slightly different injectors FREE......until your engine is running balanced fuel flows. They have the same part number but are biased toward the manufacturing tolerance needed.

Read the customer reviews. http://www.gami.com/gamijectors/gamijectors.php
 
kgruber said:
Gami will. Install a set, do the GAMI test, and if the FFs are more than .2g/hr off they will send slightly different injectors FREE......until your engine is running balanced fuel flows. They have the same part number but are biased toward the manufacturing tolerance needed.
Click to expand...

TCM/CMI says they will do the same. $569.51 vs $900.00
 
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