How to Clean Injectors

[Shadrach]

3 minutes ago, DonMuncy said:

You might pour some Hoppes #9 into a plastic sandwich baggie to make  sure it won't dissolve the baggie. If not, pour enough in the baggie to cover the injectors. Then put water into the ultra sonic cleaner, place the plastic baggie into the water and run it. The sonic waves transmit through the water, then thru the cleaner. Works well.

Brilliant suggestion!

[corn_flake]

57 minutes ago, DonMuncy said:

You might pour some Hoppes #9 into a plastic sandwich baggie to make  sure it won't dissolve the baggie. If not, pour enough in the baggie to cover the injectors. Then put water into the ultra sonic cleaner, place the plastic baggie into the water and run it. The sonic waves transmit through the water, then thru the cleaner. Works well.

Wish I had thought of that!!  

In any case, my GAMI spread is terrible.  I'm talking about more than a gallon difference.  We weren't sure if injectors needed to be clean, but since we had to remove the injectors to do the baby bottle test, we decided to go ahead and clean them before putting them back in.  In case if you are wondering, the baby bottle were dead on even between all four injectors.  My AP/IA and I will be performing intake leak test this weekend.  If that doesn't fix the problem, our next step is to remove the fuel servo and send it in to a shop for inspection.  But, right now, my money is on the intake leak.  Wish me luck!!

[carusoam]

holy cow...

Gami spreads on gami-jectors should be very close.
When they aren’t... expect that somebody lost track of which one goes where.... (log book records)

More than a gallon... that is outside of ordinary injector spreads...
 

Just when you thought crowd sourcing couldn’t possibly work so well... with such technical detail...

Don has a small family of hangar elves working 24/7 on all kinds of ideas from mechanical engineering, electrical engineering, and chemical engineering...  

Good luck with the next steps. (As requested) 

Go MS!

Best regards,

-a-

[Guest]

7 hours ago, DonMuncy said:

You might pour some Hoppes #9 into a plastic sandwich baggie to make  sure it won't dissolve the baggie. If not, pour enough in the baggie to cover the injectors. Then put water into the ultra sonic cleaner, place the plastic baggie into the water and run it. The sonic waves transmit through the water, then thru the cleaner. Works well.

The instructions that came with my ultrasonic cleaner calls this method “indirect cleaning”. Works very well and conserves the Hoppes.

Clarence

[bradp]

Saves the more expensive cleaner too. 
 

The best way to do the baby bottle test is to do with the injectors in-line.  

[Shadrach]

11 hours ago, corn_flake said:

Wish I had thought of that!!  

In any case, my GAMI spread is terrible.  I'm talking about more than a gallon difference.  We weren't sure if injectors needed to be clean, but since we had to remove the injectors to do the baby bottle test, we decided to go ahead and clean them before putting them back in.  In case if you are wondering, the baby bottle were dead on even between all four injectors.  My AP/IA and I will be performing intake leak test this weekend.  If that doesn't fix the problem, our next step is to remove the fuel servo and send it in to a shop for inspection.  But, right now, my money is on the intake leak.  Wish me luck!!

I am dubious that your bird ever needed GAMIs. Especially if they all flow at the same rate. The majority of 4 cyl Lycomings have spreads of .5 or less with no modifications.

Edited May 7, 2020 by Shadrach

[markgrue]

One suggestion.  When they say leave them to soak for 15 min don't leave them in any longer.  The Hoppes will leach the alloy metals from the brass and you will turn your expensive injectors to junk .  

 

Mark

[corn_flake]

It's actually 20 minutes as per Lycoming's instruction.  I did it in 10 minutes sessions.  Remove the injectors to wipe and brush the *exterior* of the injectors with tooth brush to help loosen up the deposit.  If the a injector looks good at that point, it doesn't go back for the second session. 

Parts of the injector appear to be made of brass.  Some brass alloy does have lead in its composition.   

[PT20J]

6 hours ago, markgrue said:

One suggestion.  When they say leave them to soak for 15 min don't leave them in any longer.  The Hoppes will leach the alloy metals from the brass and you will turn your expensive injectors to junk .  

 

Mark

I never heard that before and I don't see any chemicals listed in the SDS that would do that. But I could be wrong. Do you have some reference for that?

Skip

[carusoam]

Skip,

The hoppes site mentions what it dissolves... including lead... popular for gun cleaning...

A metals site discusses various alloys...  Brass often has lead in it...

various aviation sites discuss cleaning with hoppes...

 

I have not seen a specific fuel injector cleaning reference that says don’t use hoppes...

Sounds like lead granules in the brass structure may be at risk of being leached out...

PP thoughts only, not a metallurgist...

Best regards,

-a-

[MikeOH]

14 minutes ago, PT20J said:

I never heard that before and I don't see any chemicals listed in the SDS that would do that. But I could be wrong. Do you have some reference for that?

Skip

Hmm, free machining brass (360) is alloyed with lead.  Guns need the lead cleaned out.  Hoppes #9 is designed to clean guns...

Just sayin'...

Edited May 8, 2020 by MikeOH

[Cody Stallings]

All night in Hoppe #9.

It cleans an Etched my injectors to where they appeared new.

Inspecting them with a 10x Needle Prob, the insides like looked great as well.

[PT20J]

Hoppe's No. 9 is specifically recommended by Lycoming (SI 1275C) for cleaning fuel injector nozzles. The SI says only to soak for 20 minutes and makes no warning about possible damage. According to Hoppe's website: Hoppe's No. 9 remains the most widely used remover of powder, lead, metal fouling and rust.

Hoppe's isn't claimed to dissolve lead, just to remove it. So, because it is claimed to remove lead from gun barrels, and because some brass alloys contain a small amount of lead, we are making a big conceptual leap that it will damage fuel injectors. Before creating yet another OWT, there needs to be some authoritative reference for that conjecture, IMHO.

Skip

[dmevans]

When I torque the injectors to 60 inch pounds, the letter is at the 9 o’clock position. Which means I need to tighten the injector an additional 3/4 turn to get the air bleed to face up. My torque wrench is reading around 185 inch pounds once I turn the marking to face down at the 6 o’clock position. I’ve heard stories of cylinders cracking near the injector due to too much torque on the injector.

Am I doing this right?

[N201MKTurbo]

7 hours ago, dmevans said:

When I torque the injectors to 60 inch pounds, the letter is at the 9 o’clock position. Which means I need to tighten the injector an additional 3/4 turn to get the air bleed to face up. My torque wrench is reading around 185 inch pounds once I turn the marking to face down at the 6 o’clock position. I’ve heard stories of cylinders cracking near the injector due to too much torque on the injector.

Am I doing this right?

I would have backed it off 1/4 turn. As long as it is tight enough that you don’t unscrew it when loosening the B-nut, it is tight enough.

[LANCECASPER]

On 5/7/2020 at 11:08 PM, Cody Stallings said:

All night in Hoppe #9.

It cleans an Etched my injectors to where they appeared new.

Inspecting them with a 10x Needle Prob, the insides like looked great as well.

Wow, that looks like about $1000 worth of Hoppes #9. 

[A64Pilot]

Hoppes #9 $15 a quart and of course it stays good, you reuse it over and over. Don’t buy the tiny bottles, I used to shoot a lot.

https://www.walmart.com/ip/Hoppes-No-9-Gun-Bore-Cleaner-Powder-Solvent-1-Quart/23237549

Usually what’s used to de copper high velocity rifle barrels like 220 swift, 22-250 etc is a very high concentration of ammonia cleaning solutions, lead is usually mechanically cleaned out, I don’t think Hoppes is very aggressive on metals, not like ammonia is anyway. Hoppes goes after carbon from burnt powder really well

I used an ultrasonic with stainless steel interior, buy an ultrasonic, you’ll use it for all kinds of things from cleaning jewelry to lawnmower carburetors.

a 50/50 mix of Mr Clean and water works wonders for most stuff.

‘On edit I bought Gami’s for my IO-540, waste of money. My IO-360 runs smooth until it just loses so much power it pretty much dies, I don’t know what the “Gami spread” is but it will run smooth leaned to 5 GPH at 22 squared, won’t fly power is so low, but it’s still smooth. 

 

Edited April 14, 2021 by A64Pilot

[EricJ]

11 hours ago, dmevans said:

When I torque the injectors to 60 inch pounds, the letter is at the 9 o’clock position. Which means I need to tighten the injector an additional 3/4 turn to get the air bleed to face up. My torque wrench is reading around 185 inch pounds once I turn the marking to face down at the 6 o’clock position. I’ve heard stories of cylinders cracking near the injector due to too much torque on the injector.

Am I doing this right?

I'd do what Rich said and just back it off reasonably close to proper alignment, and if it's too loose there tighten just to snug enough.    Mine are like that, too, where you're not going to get another full turn once it hits torque.

Edited April 14, 2021 by EricJ

[bradp]

Be careful of the B nut when tightening or loosening - you can crack the line at the solder point at the neck.   

[spitzfyre]

Resurrecting an old thread...

When installing the injectors, how far into the cylinder were any of you able to get them to go? Do the shoulders have to be flush with the cylinder? I can get about 3-4 threads on mine before they tighten up. I admit that I didn't pay attention to this when removing the old ones, and I don't see any reference to this in the Mooney Service Manual.

[cliffy]

You MUST pay attention to the proper torque value !!

You can't just turn them in !!!

Get the proper engine  manual and do it correctly.

Sorry to be so firm but this is important 

Same goes for fuel line routing and securing by the AD

[EricJ]

31 minutes ago, spitzfyre said:

Resurrecting an old thread...

When installing the injectors, how far into the cylinder were any of you able to get them to go? Do the shoulders have to be flush with the cylinder? I can get about 3-4 threads on mine before they tighten up. I admit that I didn't pay attention to this when removing the old ones, and I don't see any reference to this in the Mooney Service Manual.

Lycoming Service Instruction 1275C, which should be available online if you search around, has the relevant instructions.   It says to torque to 60 in-lbs for LW-18265 nozzles, then tighten until the stamp opposite the bleed hole is facing down.    I've never been able to get them to turn much further than the 60 in-lb torque setting, so if I can get the stamp facing downward somewhere near that, then that's usually where I stop.   Sometimes there's just not a comfortable combination and the stamp isn't in an optimal spot, but I'd rather have the torque reasonably close.

[spitzfyre]

10 hours ago, cliffy said:

You MUST pay attention to the proper torque value !!

You can't just turn them in !!!

Get the proper engine  manual and do it correctly.

Sorry to be so firm but this is important 

Same goes for fuel line routing and securing by the AD

Thanks, I'm aware of proper torque procedures and have all the manuals, but blindly turning something until it reaches torque isn't correct, either. I'm only getting 3ish threads down. My concern is that this is not enough, which would indicate galled threads. They don't look all that terrible upon inspection, though, so my question is, are 3ish threads normal, or are they galling? 

[PT20J]

The injector nozzle bodies are brass and shouldn't gall. The bodies use a 1/8" NPT tapered pipe thread and the exact number of threads engaged will vary. The attached reference suggests a 1/4" engagement. I wouldn't worry about it if all the nozzles are all about the same and don't leak . If one were different that the others, I would investigate further.

DixonCatalog1.Page525.pdf

[MikeOH]

So, what bad things happen if the bleed hole is improperly positioned?