IO-360-M1B - Fixed pitch but prepped for C/S..

[PhatRV]

If you have a new IO-360-M1B engine and want to use it for FP then I recommend you get the Lycoming factory guidance for the conversion.

These are the instructions from the factory tech rep:

" I’ve got a couple illustrations I’ve attached to this email to show the process for pulling off the rear prop governor drive assembly and installing a block-off plate. You would remove the four gray-painted nuts (one of them is circled in green), and pull the drive assembly straight out. Cover plate p/n 69106 and gasket p/n 69551 would get installed over the hole and secured using the plain washers and nuts you removed, replacing the 4 used lock washers with new lockwashers p/n STD-475. The nuts will get torqued to 17 ft-lbs.

On the front of the engine, you can either put an AN cap on the elbow (something like an AN929-6), or remove the elbow and put an STD-783 allen plug into the case, using a little bit of Loctite 564 on the first 3 threads." (The elbow remains after the oil line is removed)

The drawing shows the picture of the block off plate that is installed after the governor is pulled out. This also necessitate removing the oil line which is quite easy to do.

This is the link to my post showing the the block off plate after it is installed.
https://vansairforce.net/community/s...6&postcount=19

[Steve Iacoviello]

Originally Posted by PhatRV

If you have a new IO-360-M1B engine and want to use it for FP then I recommend you get the Lycoming factory guidance for the conversion.

These are the instructions from the factory tech rep:

" I’ve got a couple illustrations I’ve attached to this email to show the process for pulling off the rear prop governor drive assembly and installing a block-off plate. You would remove the four gray-painted nuts (one of them is circled in green), and pull the drive assembly straight out. Cover plate p/n 69106 and gasket p/n 69551 would get installed over the hole and secured using the plain washers and nuts you removed, replacing the 4 used lock washers with new lockwashers p/n STD-475. The nuts will get torqued to 17 ft-lbs.

On the front of the engine, you can either put an AN cap on the elbow (something like an AN929-6), or remove the elbow and put an STD-783 allen plug into the case, using a little bit of Loctite 564 on the first 3 threads." (The elbow remains after the oil line is removed)

The drawing shows the picture of the block off plate that is installed after the governor is pulled out. This also necessitate removing the oil line which is quite easy to do.

This is the link to my post showing the the block off plate after it is installed.
https://vansairforce.net/community/s...6&postcount=19

PhatRV
I don’t mean to give you a hard time. My only reason for posting was that I did not want others to take your advice and end up with a major unexpected oil leak, particularly in flight. There is a reason that Van’s instructions and the Lycoming service instructions exist. To prevent the front plug from being pushed out by oil pressure.

Did your factory tech rep tell you why you should ignore Vans and Lycoming’s instruction?

Is there something different with the IO-360-M1B that allows not removing or poking the back plug?

At minimum the factory rep should tell you why pressure will not build up and push out the front plug. There may be a very good reason but you have not shared what that is. (I hope you are correct)

For what it’s worth I poked the hole on my O-320-D1A and now have over 700 hours on it. If I had to do it again I would have left the oil line in place as PilotjohnS describes.
Steve

[jcarne]

Originally Posted by PhatRV

If you have a new IO-360-M1B engine and want to use it for FP then I recommend you get the Lycoming factory guidance for the conversion.

These are the instructions from the factory tech rep:

" I’ve got a couple illustrations I’ve attached to this email to show the process for pulling off the rear prop governor drive assembly and installing a block-off plate. You would remove the four gray-painted nuts (one of them is circled in green), and pull the drive assembly straight out. Cover plate p/n 69106 and gasket p/n 69551 would get installed over the hole and secured using the plain washers and nuts you removed, replacing the 4 used lock washers with new lockwashers p/n STD-475. The nuts will get torqued to 17 ft-lbs.

On the front of the engine, you can either put an AN cap on the elbow (something like an AN929-6), or remove the elbow and put an STD-783 allen plug into the case, using a little bit of Loctite 564 on the first 3 threads." (The elbow remains after the oil line is removed)

The drawing shows the picture of the block off plate that is installed after the governor is pulled out. This also necessitate removing the oil line which is quite easy to do.

This is the link to my post showing the the block off plate after it is installed.
https://vansairforce.net/community/s...6&postcount=19

Ya you need to quiz Lycoming a little more on this. That picture I posted was directly from Lycoming Service Instruction 1435. (which applies to all direct drive engines) The oil has to go somewhere, certainly don't want it to go out the front plug...

Personally I would have followed what John S recommended (which has also been recommended in the past by well respected engine builders). Also worth noting that his recommendation came from Lycoming too as mentioned in his last post.

[PhatRV]

I called Tyler at the Lycoming and he confirmed that by removing the oil line from the rear governor drive and plug the forward crank oil port, there won't be any oil coming from the rear governor to pressurize the forward hollow crank area. This case is only applicable for the rear-mounted governor like the IO360-M1B. The Lycoming engine that has the forward mounted governor works differently so the description I posted doesn't work for that type of configuration. I think the forward mount governor always pump oil into the hollow crank and thus, a relief hole must be punched out to prevent oil pressure build up in this area (just guessing from studying documentations of different IO360 engine types for the last month)