O-320 returning to service after 25+ years in storage

[PaulvS]

25+ years ago I bought a mid-life O-320-E2C for the RV-6A that I had started building. It has taken much longer than expected but soon it will be time to install the engine and I'm looking for suggestions to help get it prepared for use.

The engine was field overhauled when I got it and upgraded to 160 hp and test run and then the oil was drained. AD's were also completed for new oil pump gears, crank bore seal and a couple of other items. Since then the engine has been stored indoors in my study in a dry climate. During the first few years of storage I sprayed LPS 3 anti-corrosion spray into the cylinders and used dessicant plugs in the top spark plug holes. The dessicant has not been refreshed in a while but I just inspected inside the cylinders with a borescope and there is no sign of any corrosion and the waxy film from LPS 3 is still present. All of the pipe fittings and vents have been capped.

I'm expecting to need to do the following:
- Fit a new or rebuilt MA-4SPA carburetor
- Fit a new mechanical fuel pump
- Get the Bendix magnetos inspected and serviced as required
- Consider fitting a spin-on oil filter to the engine or firewall
- Put oil in the engine and turn it upside down to soak the camshaft before fitting it on the mount
- Wash out the cylinders to remove LPS 3 before first start

Is there anything else that would be important to do?

Thanks!

 

[Mcmark]

Remove this oil galley plug and use a caulk tube to fill with oil. You can buy fresh tubes on Amazon. This will insure the oil pump is primed. Likely has lost prime sitting for such a long period. Mine did.

 

[Ironflight]

You might think about that 25-year-old fuel pump diaphragm, and how stiff and crusty it might be….and then think about how Mitch easier it is to change a pump OFF the airplane rather than ON the airplane…..

 

[newt]

Same for the front oil seal? And anything else made of rubber, really.

- mark

 

[PaulvS]

Remove this oil galley plug and use a caulk tube to fill with oil. You can buy fresh tubes on Amazon. This will insure the oil pump is primed. Likely has lost prime sitting for such a long period. Mine did.

I will do that, thanks.

 

[PaulvS]

You might think about that 25-year-old fuel pump diaphragm, and how stiff and crusty it might be….and then think about how Mitch easier it is to change a pump OFF the airplane rather than ON the airplane…..

I will order a new pump, and will no doubt learn something during installation.

 

[PaulvS]

Same for the front oil seal? And anything else made of rubber, really.

- mark

The front seal can be changed relatively easily I believe. But other rubber parts e.g. the seals on the pushrod tubes would mean removing the cylinders, yes? The rubber appears OK and is still pliable and is not at all cracked or hardened.

 

[Ironflight]

The front seal can be changed relatively easily I believe. But other rubber parts e.g. the seals on the pushrod tubes would mean removing the cylinders, yes? The rubber appears OK and is still pliable and is not at all cracked or hardened.

You don’t have to remove the cylinders - just the rocker covers, pushrod tube retainers, and they pushrods. I have found that with age, the O-rings at the top end of the cylinder (that seal the pushrod tubes to the head) start leaking due to age before the seals at the case end, and once the tube is out, its a no-brainer to replace those. I’ve replaced all the pushrod seals on an engine in a couple of hours - its as easy to do on the plane as on the engine stand, so if you want to wait and see if they leak in service, its not a big deal.

 

[OKAV8r]

If the engine is set up for a fixed pitch prop, and I assume it is, pop the front plug (STD 1211?) out of the crank and inspect the inner crank bore as described in FAA AD 98-02-08 and SB 505B. While you're in there, run a borescope back through in inner bore, and take a look in the crankcase. Depending upon your borescope and the rotational orientation of the crank, you might even be able to get a peek at the cam.

 

[[email protected]]

Pull the sump off and you can probably stuff the borescope up through the case crack and see the front three lobes of the cam if yo are concerned. about rust up there.
I have an 0-360 that sat in dry warm spaces that is 30 years since OH and I did that and everything looks clean and no rust anywhere..
My luck varies though Fixit

 

[jrs14855]

borescope

Depending on how the aft plug location is configured you may not be able to get a borescope thru there.

 

[YellerDaisy]

I don't really know any secrets and what I do know will just scare you but that may be better than an inflight issue...

I recently overhauled an O-360 that was an unused factory reman... wait for it... 46 years ago. Yup... 1977. I even have an official Lycoming "Remanufactured Zero Time Engine Certificate".

It was well preserved and kept in a dry climate. Upon disassembly, I found the preservative had 'hardened' to a shellac like substance. It was filled to about the centerline of the crank so half the crank, half the rods, half the pistons (and everything below) were coated. The rings were completely gummed up with the stuff and most of the lifters had 'issues' that solvent/cleaning mostly resolved (except for two of them). Some pics here.

The positive is that nearly all parts were (still) brand new/serviceable. The negative is that the engine would not have survived very long had I elected to run it.

In addition to all of the above, I would also want to get a look at the crankshaft oil galleries - especially if it has the older "sludge tubes."