O-235-C1 questions please

C

cubdrvr

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I have a '66 7GCBC with an O-235-C1. It sat idle for a long time. Cylinders are scored and rusty.
Local overhaul shop says no available parts anywhere for this engine. Can anyone verify this?
If so, what alternatives might be available? Thanks !
 
Clean the bores and fly the socks off of it? Pre-oil. If the rust isn't too bad, maybe just let the rings scrape it clean?

We have successfully taken two Continentals through that process - we first pressurized the engine with Marvel Mystery oil, then dumped that and used 50 weight AD. The trick is to take the valve covers off, and rotate the prop while observing oil squirting from each rocker arm. Both engines are quite happy, after laying on the hangar floor for a quarter century.

Too bad you are so far away - I would lend you our pre-oiler.
 
OK thanks Bob........... further checking in minimum logs reveals ECI cylinders. J&J appears to have rings available.....still waiting for confirmation.
However the ring set currently on these cylinders is the ST204 with the 73851 piston. I think the ST204 is for choked cylinders and the ST202
for straight cylinders. If that is the case would it not affect ring gap? I think I need the ST202.
But I like your post re: clean and fly :cool:
 
I just had one rebuilt. Those cylinders and rings are hard to come by, but not impossible. J&J does have rings, but be prepared to pony up. I don't have the rebuild invoice handy, but I think they were $500/ set. From what I understand most of the cylinders are coming off old engines and being reconditioned. The engine shop told me that if I was planning on flying it to overhaul, find a O-320.....

Pete
 
Here's a couple of current listings from Craigslist. It seems like O-235 stuff comes up fairly often. Good luck with your search.

Lycoming 0-235 engine PARTS - aviation - by owner - airplane aviation parts - craigslist

Lycoming 0-235 parts; have remaining: four 0-235 rocker arms $200/ 0-235 camshaft gear $400/ eight 0-235 push rods $100/ one 0-235 piston std. $125. or purchase all for $500.
phoenix.craigslist.org phoenix.craigslist.org

Lycoming O-235-C - aviation - by owner - airplane aviation parts - craigslist

This engine was pulled for a 160hp upgrade.
dallas.craigslist.org dallas.craigslist.org
 
I got more folks :( ............
The oil cooler ( if you can call it that) is an square aluminum box that surrounds the oil screen housing and is powered from outside ram air.
Never have seen that one before. So..........the way it is mounted ( I'm sure some of you have experienced this) requires me to remove the left mag to access the housing bolts from the rear of the box with a short extension that just fits with enough wiggling to get it on the bolt head.
When I did get the box and housing off I'm thinking this is nuts if one has to do this every 25 hr. oil change. Must be another way. I'm thinking
of modifying the box into a 2 piece unit. What say you guys? Better mousetrap?
 
That box sounds like someone's attempt at trying to lower oil temps. If it were I, I would remove that oil box all together. Especially for the cooler spring temps and in anticipation of checking that screen on a regular basis here at the beginning.

I would drain and change your oil. Pull all the spark plugs. Spray fogging oil in all cylinders and in the crank case through the oil fill port (this part probably does very little to nothing, but makes me feel like I tried). If you don't have a pre-oiler, I have used the starter.... Again, plugs out, until I get oil pressure. Don't burn up your starter. 30 sec on, 1 min off. Then give the starter a good 15-20 mins to cool if it gets warm. This might take several cranks. When you get oil pressure,
Install the spark plugs and fire it up. If everything feels good, fly it HARD for 2-3 hrs before you check compressions. And change oil and check screen 5-10 hrs.

Like Bob, I've done this to several engines that were sitting for decades.
 
If you think you're going to run it as is after some prep, it might be a good idea to put a B&C oil filter adapter on it and let the filter catch whatever debris is generated in those first few hours. I agree with @Tangogawd , the box around the oil screen housing isn't stock but could there have been something going on in the engine causing abnormally high oil temps which is why it was parked?

I'm not an A&P but from what I've witnessed from others' experiences, it'll run great for anywhere from 50 to 200 hours before the cam starts to shed metal and take the engine with it, your mileage may vary.
 
I'm learning on this bird. The box surrounding the oil screen housing is factory and used as the ONLY oil cooler, so can't install a filter kit as the engine would lose it's only cooler. I'm going to modify the box to make it easier to access.
 
Where have you seen a box around the oil screen in a parts manual? Has anyone here ever seen this cooler box on an O-235?

A call to B&C about their filter adapter and the cooler box would probably reveal useful insights. They are very helpful and accessible by phone.
 
No citabria I have ever worked on has had that box. Nor does a GCBC have a O-235. That's a ECA engine. But that's besides the point.

Just checked my parts manual for 64-73 7ECA, 7GCAA, 7GCBC, and I didn't find anything resembling a cooler for the oil screen housing.
 
that is a Chat GPT screen shot? I searched the Lycoming part number and didn't find anything.

I'd be curious to see a pic of the part we're talking about.
 
i tried a google search with Lycoming and that part number but didn't see the part in your photo. The O-235's I've seen haven't had an oil cooler or problems with high oil temps. I've never seen that shroud part before. The O-320's typically have an actual oil cooler.

If wouldn't maker sense for your plane to have been used as a tow plane for banners or gliders with an O-235 which might explain the need to improve oil cooling. If it were me I'd preferr to have the oil filter there than a cooling shroud of questionable value. If the housing doesn't have cooling fins for heat transfer, I'd guess the extra airflow from that shroud isn't doing a whole lot.
 
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