Lycoming O-145 Head Torque

[wmfife]

Re: Lycoming O-145 Head Torque

Don't know whether or not this will show them. They sit right behind the #3 and #4 stacks and attach to the oil pan.

This was taken at pre-buy with owner's cam. Mine is a Nikon and seems not to like the batteries I use.

Will improve on this as soon as I find a good camera repair shop in this slow small town...

[Howard Wilson]

Re: Lycoming O-145 Head Torque

If it's what I think you are talking about: h

[wmfife]

Re: Lycoming O-145 Head Torque

Howard, et. al,

They are very hard to get a good look at from outside the engine compartment. You literally have to put your head (or perhaps camera) down under where the mags are- and if like me you have the massive Bendix ones that's easier said than done.

They're attached to the bottom aft portion of the oil pan at each side with a couple of studs (-bolts? ... I'm not by it right now.. no laptop so relying on memory) passing through a drilled flattened flange portion at the lower end of each tube bent approx. 45º. This 45º bend is to accommodate the angle of the support tube when installed. Each rear stack has a narrow hollow 1-2" spur that the rod fits around, welded to the inside stack face near the upper end pointing down at approx. this same angle. This I am guessing is more or less the point of balance for the whole system. When in place the rods form a spread-out V looking forward, connecting the stacks to the oil pan.

Trick is to get the system up tight at the cylinders with no sleeves showing as you tighten the exhaust clamps while the bases of the spurs on the stacks are fully bottomed out and equally tight inside the ends of these support tubes. Mine were not and I have no explanation why. But knowing what I know now when I bought the plane would likely have saved me a few thousand$$ in new heads... to say nothing of the risk of engine fire in flight..

I just ordered a new battery charger hoping it's the fix I need for this $200 digital cam. But I am going to try and see if I can borrow one in the meantime to get some pics in real time. Stand by. This is too important for owners of the Lycoming-powered models not to have access to and neither the engine nor exhaust manufacturers have published much if anything on it that I know about.

[Bob Waldron]

Re: Lycoming O-145 Head Torque

Bird,

Here are three photos of my 'right side' exhaust support. First photo shows connection at bottom of the case. Second photo shows top of support rod, and the 'Crows Foot' that is welded to the exhaust pipe -- you are looking past the exhaust pipes and intake manifolds. The third photo show the top again, but from the firewall looking forward. You can see the 'crows foot' welded to the exhaust manifold and the support rod going up into the Crows Foot. Note that there are some washers between the Crows Foot and the washer that I welded to the Support Rod. My new engine has cooling fins on the bottom of the case. I think that the case came from a GO-145. The fins make the bottom Support Rod attach points 3/8 inch lower than on a case without fins. My added washers make up that 3/8 inch.

[Bob Waldron]

Re: Lycoming O-145 Head Torque

For some reason, the FIRST photo did not make it. This is the attachment to the bottom of the case.

[Bird]

Re: Lycoming O-145 Head Torque

Thanks for the pictures, had no idea that they were needed

[1938BF50]

Re: Lycoming O-145 Head Torque

I THINK I remember seeing this as a factory service bulletin. Go to Barnstormers CAP site and look at the service bulletins that he has so graciously provided for our use.

[wmfife]

Re: Lycoming O-145 Head Torque

Thanks for the pictures, had no idea that they were needed

If they were never installed on yours then worm-screw adjustable SS band hose clamps have been suggested for accomplishing the needed support. Apply creatively... they need to go around the entire assembly. I have no drawings just an O-145 TC-certified mech's recommendation.

Still best to have a set installed if you can.