Suction screen plug

[MarkCFI]

Doing an oil change and removed the suction screen and plug.

For the life of me I can’t get it to start back in the threads. I had to take a break but I’m wondering if there is some trick or whether the threads may be off?

I have done this before but not with this engine.

Thoughts?

 

[BobTurner]

Maybe something strange, like the new crushwasher is the wrong size (too thick) so the threads won’t engage???

 

[Dan 57]

Not sure, but try to first insert the screen into the plug's recess, and then screw the plug with the screen as an assy.

 

[D-Dubya]

Just to make sure the threads didn't get damaged, try spinning just the plug back on without the screen. If that goes well, then the screen isn't fitting properly into the recessed areas it's designed to rest in. If it's not straight, that screen can get irreparably damaged when you tighten the plug. If it doesn't fit, don't force it...

 

[MED]

Doing an oil change and removed the suction screen and plug.

For the life of me I can’t get it to start back in the threads. I had to take a break but I’m wondering if there is some trick or whether the threads may be off?

I have done this before but not with this engine.

Thoughts?

I just checked my oil screen. If the screen is not fully inserted in the plug, it may keep the plug threads from starting. Good luck.

 

[MarkCFI]

Thanks for the suggestions.

I literally tried each of those. With the screen first, with the screen in plug, just the plug no screen, no gasket, with gasket, with and without anti-seize…..,

I could not get the threads to start and after an hour or so I finally had to walk away…

I’m going to try again tomorrow and maybe try to insert it while I lay under the engine instead of from the side.

It came out of the hole, there must be a way it goes back in………

Thanks again

 

[jrs14855]

Thanks for the suggestions.

I literally tried each of those. With the screen first, with the screen in plug, just the plug no screen, no gasket, with gasket, with and without anti-seize…..,

I could not get the threads to start and after an hour or so I finally had to walk away…

I’m going to try again tomorrow and maybe try to insert it while I lay under the engine instead of from the side.

It came out of the hole, there must be a way it goes back in………

Thanks again

 

[jrs14855]

No anti seize. Engine oil on threads. Screen fully into plug, then just move it around a little until it drops into the recess. The plug should tighten freely by hand until it contacts the washer. The screen should drop into the cavity before the threads engage.

 

[koupster]

I literally tried each of those. With the screen first, with the screen in plug, just the plug no screen, no gasket, with gasket, with and without anti-seize…..,

I could not get the threads to start and after an hour or so I finally had to walk away…

Mark,

If the plug unscrewed easily once it was loosened, the threads should be OK, but look at the end of the threads with a magnifing glass to make sure. Try again with just the plug, but turn the plug counter-clockwise until you feel the plug drop into the threads. Then go clockwise from there.

Success? Now put the screen in and try again. A tiny bit of grease can hold the screen straight so that the plug can be screwed in by hand until it touches the gasket. It's easy to crush the screen if it's not positioned correctly and a wrench is used early on.

I've struggled with spark plugs the same way when I thought I had the angle right but didn't.

The engine builders have it easy here, since the engine is usually vertical and the screen just drops in and its correct anignment can be seen. Gravity works against the maintainers in the field.

Good luck! Standing by for a follow-up from you.

 

[MarkCFI]

I brought the e plug home and it definitely looks like there’s a small ding near the start of the threads. Looks like it was dropped prior?

I don’t have a die that size to try to chase it. Try with a tiny file or hacksaw blade to clean it?

Research says it’s a 1”x20 thread? Any know thread chaser I could potentially pick up locally?

 

[Dan 57]

Try with a tiny file

would be my immediate solution. Then trying again to thread it on, with some pressure whilst making sure it is straight, first without the screen, and then with screen and crush gasket for final assembly.
As someone wrote above, it was in, gotta go back in again, good luck

 

[Roadjunkie1]

I brought the e plug home and it definitely looks like there’s a small ding near the start of the threads. Looks like it was dropped prior?

I don’t have a die that size to try to chase it. Try with a tiny file or hacksaw blade to clean it?

Research says it’s a 1”x20 thread? Any know thread chaser I could potentially pick up locally?

View attachment 60412

That doesn't look like it is in an area that would affect starting the threads as it is in front of where the threads would start to grab. But..........

 

[MarkCFI]

Well here’s the solution.

What I didn’t notice from the side of the aircraft was that there was a hangar for the sump heater that was interfering just enough to keep the plug from threading.

Shen I looked from the bottom I could see it so I loosened it up and moved out of the way and the plug went right in.

Thanks for the quick responses. Now on to the most challenging part. The safety wire for that plug.

 

[MarkCFI]

I should also say that this is the point I get so giddy that I install the gasket, torque it up, safety it and then walk back to my bench and notice the screen…..,,,

Not this time.

Thanks again.

 

[koupster]

I brought the e plug home and it definitely looks like there’s a small ding near the start of the threads. Looks like it was dropped prior?

I don’t have a die that size to try to chase it. Try with a tiny file or hacksaw blade to clean it?

Research says it’s a 1”x20 thread? Any know thread chaser I could potentially pick up locally?

View attachment 60412

Mark,

I agree to start with a tiny triangular file. I see thread damage on the starting threads to the right of center in the (very nice) picture. There's damage further down as well. Also, grit in the threads and what looks like hardened sludge in the sealing washer area.

1"-20 UNEF (extra fine) nuts and dies are available, but probably not locally. You can take a 1"-20 UNEF nut and make several hacksaw cuts in the threads to make a thread chaser. That nut will also let you know where the threads are damaged as you screw it on. 1"-20 UNEF dies are also available. The type of die with a screw adjustment (for thread depth) can serve as a thread chaser in its loosest position.

1"-20 UNEF bolts to check the threads in the sump will be much harder to find. If you buy the 1"-20 UNEF die, you can put some threads on a piece of 1" round stock to check the threads in the sump.

Good luck. Some sources below.
https://www.scagparts.net/hydro-gear-51821-1-20-slotted-hex-nut/
https://www.amazon.com/Universal-Outside-Thread-Chaser-Similar/dp/B07XGQQSY6
https://www.mscdirect.com/product/d...2ODkLjlIUOviwtPM-9xbozqJulHEvxMyXlj98oGcHFuP4

 

[Dan 57]

this is the point I get so giddy that I install the gasket, torque it up, safety it and then walk back to my bench and notice the screen….

Love it Could happen to me too, as just too human sometimes...
Thanks for the entertainment

 

[MED]

Well here’s the solution.

What I didn’t notice from the side of the aircraft was that there was a hangar for the sump heater that was interfering just enough to keep the plug from threading.

Shen I looked from the bottom I could see it so I loosened it up and moved out of the way and the plug went right in.

Thanks for the quick responses. Now on to the most challenging part. The safety wire for that plug.

View attachment 60457

Glad you got it in. Sorry you have to safety wire it now. Awful task.

 

[Mel]

Glad you got it in. Sorry you have to safety wire it now. Awful task.

A little extra safety wire practice never hurt anyone. The important thing is that he found the problem and corrected it.

 

[MarkCFI]

Mark,

I agree to start with a tiny triangular file. I see thread damage on the starting threads to the right of center in the (very nice) picture. There's damage further down as well. Also, grit in the threads and what looks like hardened sludge in the sealing washer area.

1"-20 UNEF (extra fine) nuts and dies are available, but probably not locally. You can take a 1"-20 UNEF nut and make several hacksaw cuts in the threads to make a thread chaser. That nut will also let you know where the threads are damaged as you screw it on. 1"-20 UNEF dies are also available. The type of die with a screw adjustment (for thread depth) can serve as a thread chaser in its loosest position.

1"-20 UNEF bolts to check the threads in the sump will be much harder to find. If you buy the 1"-20 UNEF die, you can put some threads on a piece of 1" round stock to check the threads in the sump.

Good luck. Some sources below.
https://www.scagparts.net/hydro-gear-51821-1-20-slotted-hex-nut/
https://www.amazon.com/Universal-Outside-Thread-Chaser-Similar/dp/B07XGQQSY6
https://www.mscdirect.com/product/d...2ODkLjlIUOviwtPM-9xbozqJulHEvxMyXlj98oGcHFuP4

Very good info. You have a sharp eye.

I did clean whatever that gunk was out of the threads as well as dress those nicks. I suspect it was some type of sealant.

Thank you.

 

[jrs14855]

Very good info. You have a sharp eye.

I did clean whatever that gunk was out of the threads as well as dress those nicks. I suspect it was some type of sealant.

Thank you.

For the next time-there's a neat little tool called a thread file. Designed for the purpose of cleaning up dings like on that plug. MSC probably has them.