How to loosen a stuck oil drain plug o-320

[ve0kog]

Hi folks,

During the last oil change, we attempted to install the antisplat oil heater but couldn't remove the "spare" oil drain plug. It didn't respond to moderate force. The plug has a square head, and it seems the corners would round off if any more force is applied. It was installed during the engine overhaul with Loctite 467 sealant about 400 tach hours ago and never moved since then.

We tried soaking the threads with penetrating oil, but it didn't help.

I was wondering if anyone has encountered this problem before and can offer some advice.

Would it be safe to try to loosen it with an impact driver and a suitable socket?

the plug looks like this

 

[paulsmeds]

We had the same problem when adding a second oil temp to the probe at the top front of an IO360A1A. We ended up heating the area around the plug after soaking with penetrating oil. Instead of trying to loosen where we were having no luck, we put pressure to tighten. Sounds counter intuitive but we could feel it go a tiny bit tighter and then it loosened up easily. Just my experience but of course be careful you don’t want to crack the case or strip the head of the plug.

 

[Avanza]

Hi folks,

During the last oil change, we attempted to install the antisplat oil heater but couldn't remove the "spare" oil drain plug. It didn't respond to moderate force. The plug has a square head, and it seems the corners would round off if any more force is applied. It was installed during the engine overhaul with Loctite 467 sealant about 400 tach hours ago and never moved since then.

We tried soaking the threads with penetrating oil, but it didn't help.

I was wondering if anyone has encountered this problem before and can offer some advice.

Would it be safe to try to loosen it with an impact driver and a suitable socket?

the plug looks like this

View attachment 71720

For Disassembly1. Remove with standard hand tools.2. Where hand tools do not work because of excessive engagement length or large diameters (over 1"), apply localized heat to approximately 250 °C (480 °F). Disassemble while hot. https://datasheets.tdx.henkel.com/LOCTITE-567-en_US.pdf

Good luck

 

[RV7 To Go]

Pick up a square socket of the correct size. Drain the oil. Remove the safety wire. Use a heat gun (not a hair drier) to heat the case around the plug. Should come out ok, with a little force.

 

[ve0kog]

I bought a heavy duty pipe plug square socket (it was either 5/8 or 9/16 with a 1/2 inch drive) and the oil plug gave in with some leverage. Did not have to resort to hammering or heat or impact driver. With the right size square socket seemed like there was no chance of rolling off the corners. Took a little more than 10 minutes but the antisplat oil heater is in.

 

[Mike T.]

For future reference to all. A "tapered pipe thread" will always tighten easier that loosen. Having been a mechanic for over 30+ years, I have taught that trick to many young guys entering the field. All it needs is a tiny bit of movement in the tightening direction, and then it will come right out. This works with any tapered pipe thread whether it is a plug, fitting, or even plumbing pipes in your house. Try it. works every time.