Fuel spider,divider, manifold

MooneyDriver78

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Tom
I’m looking for picture of the inside. We routinely clean fuel injectors but the divider is never mention, parts manual treats as 1 part. My fuel balance isn’t I like it to be, already had my gami injectors cleaned, so I think cleaning the divider is next step but would like to understand how it works.
 
Not much to it. There's a poppet valve in it that shuts the flow off when the fuel pressure falls off, to keep the injector lines full. There's a last-chance screen in there to stop debris. It's a chamber with an appropriate number of outlets.

Maybe a good check of the fittings in it, and the injector lines, for any obstructions or kinks in the lines. Lycoming has an AD that mandates an annual/110 hour inspection of those lines: www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgad.nsf/0/b39e0b81acb0f30786257ecf005d80c7/$FILE/2015-19-07.pdf
 
Not much to it. There's a poppet valve in it that shuts the flow off when the fuel pressure falls off, to keep the injector lines full. There's a last-chance screen in there to stop debris. It's a chamber with an appropriate number of outlets.

The screen you mention, how do you clean it, removal of all screws ?
I have 2 cylinders run richer than the other 2, can you think of anything that would cause this?[/QUOTE]
 
The screen you mention, how do you clean it, removal of all screws ?
I have 2 cylinders run richer than the other 2, can you think of anything that would cause this?
[/QUOTE]

Disassembling that, at least in Canada, is specialized maintenance, not for the average mechanic. The US might be different.

If you have a difference in EGTs, you might have a mixture problem or you might have some poor sparkplugs or leads. Mag checks are fine, but they don't tell you what's going on when both plugs are firing. If one fires a few degrees ahead of the other, and that second plug is weak, the pressure rise after the first spark will prevent its firing and the EGTs go nuts.

Ignition causes a majority of headaches and expends a lot of money as people chase fuel stuff.

Bsides, in these rather primitive engines, homogenous mixture distribution is rare and almost impossible. The advent of fancy engine monitors, with their huge dumping of information on the pilot, cause more worry than assurance, I think. These same old engines ran fine and reliably for many decades before we had that stuff.
 
Disassembling that, at least in Canada, is specialized maintenance, not for the average mechanic. The US might be different.[/QUOTE]
Same here, specialized maintenance only to be done by a certified shop. :(
 
Disassembling that, at least in Canada, is specialized maintenance, not for the average mechanic. The US might be different.
Same here, specialized maintenance only to be done by a certified shop. :(
Where is that written?
 
There isn't much to it, if you want the piece of mind send it off to be overhauled. I think it cost me $250.00 or so to have mine done. If that screen is clogged enough to matter I would consider going through the entire fuel system.
 
There isn't much to it, if you want the piece of mind send it off to be overhauled. I think it cost me $250.00 or so to have mine done. If that screen is clogged enough to matter I would consider going through the entire fuel system.

But how would I know if I can’t take it apart to inspect it? It doesn’t sound like it has moving parts, I just wanted to inspect,clean the screen and give it bath in carburetor cleaner. What makes it so special?
 
But how would I know if I can’t take it apart to inspect it? It doesn’t sound like it has moving parts, I just wanted to inspect,clean the screen and give it bath in carburetor cleaner. What makes it so special?

You can take it apart if you would like, I took mine apart before sending it out. You will need a new gasket if you plan to put it back together. I didn't like how hard the rubber diaphragm had become so I sent it out and had it overhauled, seemed like a no brainer considering how cheap it was.
 
Where is that written?
I do not know where it is written but I can attest that Continental engineers told me as an A&P I could not disassemble my spider and clean the screen and the AI that works with me agreed it had to be sent out to a specialized shop. AirPower replaced the spider at no charge even though we were 2 months beyond the end of our warranty period on our Reman “0” time IO 520 when we had fuel contamination issues. They also replaced all 6 lines and injectors at no charge. I can not say enough good things about Air Power service for our engine problem!
 
FAR 65.
65.81 General privileges and limitations.
(a) A certificated mechanic may perform or supervise the maintenance, preventive maintenance or alteration of an aircraft or appliance, or a part thereof, for which he is rated (but excluding major repairs to, and major alterations of, propellers, and any repair to, or alteration of, instruments), and may perform additional duties in accordance with §§65.85, 65.87, and 65.95. However, he may not supervise the maintenance, preventive maintenance, or alteration of, or approve and return to service, any aircraft or appliance, or part thereof, for which he is rated unless he has satisfactorily performed the work concerned at an earlier date. If he has not so performed that work at an earlier date, he may show his ability to do it by performing it to the satisfaction of the Administrator or under the direct supervision of a certificated and appropriately rated mechanic, or a certificated repairman, who has had previous experience in the specific operation concerned.

(b) A certificated mechanic may not exercise the privileges of his certificate and rating unless he understands the current instructions of the manufacturer, and the maintenance manuals, for the specific operation concerned.

Here is the catch.. Ever done it before? No. Find some one who has to show you how,
 
For one, the instructions for O/H of the fuel spider are not part of the MM for my aircraft of powerplant. *shrug*

The instructions for inspecting or overhauling a magneto likely aren't found in the publications you referenced either, yet a properly rated mechanic can work on and return them to service.
 
Call Don Rivera at Airflow Performance for guidance. He can also IRAN it for you, if you'd like. Nice guy and reasonable costs.
 
For one, the instructions for O/H of the fuel spider are not part of the MM for my aircraft of powerplant. *shrug*
So what?

It's FM, it just started working really good again :)

And don't forget what 43.9 really says.
 
The instructions for inspecting or overhauling a magneto likely aren't found in the publications you referenced either, yet a properly rated mechanic can work on and return them to service.

So what?

It's FM, it just started working really good again :)

And don't forget what 43.9 really says.
So are both y'all saying that you neither need a manufacturer's MM for a part nor be certified to O/H the part and you can legally RTS?

I understand that every idiot can O/H simple parts (like the SkyTec toy to replace the sheer pin) but is it truly legal?
 
So are both y'all saying that you neither need a manufacturer's MM for a part nor be certified to O/H the part and you can legally RTS?
yes
Don't confuse return to service with overhaul.
two very different subjects.

Would disassembly, cleaning, reassembly be considered a repaired as required, or overhaul?
Read 43.2 and 43.9
 
So are both y'all saying that you neither need a manufacturer's MM for a part nor be certified to O/H the part and you can legally RTS?

I understand that every idiot can O/H simple parts (like the SkyTec toy to replace the sheer pin) but is it truly legal?
What would you call 6 screws, a gasket, and a screen?
 
What would you call 6 screws, a gasket, and a screen?

I would call it normal maintenance, in my case it’s 4 screws. All screens, filters cleaning should be considered normal maintenance, this isn’t rocket science.
So an AP can overhaul an engine, but not the fuel divider...and this makes sense to who?
 
I would call it normal maintenance, in my case it’s 4 screws. All screens, filters cleaning should be considered normal maintenance, this isn’t rocket science.
So an AP can overhaul an engine, but not the fuel divider...and this makes sense to who?
To the guy who does not publish the manual.
 
need a manufacturer's MM for a part
If there is a MM for the part. Unfortunately, not everything is documented in such a format yet things break and they have to be fixed. For an example, look at the manuals for a Super Cub.
be certified to O/H the part
The certification is with the A&P certificate. How the mechanic can use that certificate is in Part 65 as stated earlier. And Part 43 provides the required references a mechanic must use when performing work under his certificate. One unique item found in both Parts is that they both provide specific examples but also include a catchall "to the satisfaction of the Administrator." So even if a part doesn't have a service manual or is installed on a new variant of an aircraft model, there is a legal method for a mechanic work on it and fix it.
you can legally RTS?
but is it truly legal?
Yes, all legal. It's easier to list the specific items a mechanic is prohibited from working on than a list of those items they can. As for RTS, a certified mechanic can not "return to service." Only a person with a private pilot certificate or higher can RTS. A mechanic can only approve for return to service.
 
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