A-65-8 Continental

I have an A-65-8 that just been overhauled. I'm getting 7 lbs of pressure at idle on left side of engine and no pressure on right side of engine.
Installed a new accessory case, oil pump gears and cover plate. New spring and plunger for oil pressure relief. I'm get oil to main bearings, camshaft journels, and to cylinders on left side. Get oil to right chamber but not to cylinders on right side and no oil pressure. Dismantled engine checked tolerances on all components, every thing is fine. Anybody out there have any ideas? Not sure where to go next.

Had the same problem years ago on my Luscombe 8A. It had sat for about a year. I squirted oil into every hole I could find to pre-oil it. No dice. Then I recalled some old timers years before my Luscombe dealing with the same problem. I helped them tip it up until the prop was on the ground for about a minute. We then put the tailwheel back on the ground and fired it up. Good to go. I then tried it with my Luscombe and it worked the same. Lots of oil pressure.

I'm not sure what was going on. The oil pump is on the rear acc case and the sump is on the bottom. But it worked for me. Let me know how it turns out. I'm guessing that you don't have a nose wheel to get in the way.


Bob

Thanks for the tip Bob. We tried this. No change.

I would try or consider:

Oil pickup tube - check for pin holes, crush washer torque, plugged tube, etc

Correct part number of bearings, possibly using undersize crank with normal bearings

Here is the KILLER - oil pump gears - the back plate must be flush all the way around. The accessory cases warp
and I have been able to slide a feeler gauge under one or more sides. If the back plate is flat, use it as a sandpaper
holder and true up the accessory case. 320 or 400 grit sandpaper followed up by 600 grit will do the trick.
Be careful how you retorque the gear back plate. The accessory cases are very soft and I usually stop when it
feels snug. This is the one time I do not follow the manual's torque recommendations.

Pete

I don't have a specific suggestion, but here is a link to a lot of information on small Continental engines and trouble shooting problems.

http://www.bowersflybaby.com/tech/fenton.htm

We tried this numerous times. Still no results. But think it may have to be done again. All indications lead to oil pump. Just can't understand how I can have oil pressure on one side of engine only.

I've sent Harry an email, still waiting on reply.

Randy Thompson is the resident small Continental guru on the Cessna 120 - 140 Association. He's very helpful and friendly. I'd check with him. Randy Thompson (530) 357-5440

Sorry for asking a dumb question, but how do you know there's no pressure on the left side? As far as I know there's only one oil pressure port and it's below the oil pressure relief valve hole, on the right, rear of the accessory case.

Quote:

---

Originally Posted by yocum137

Sorry for asking a dumb question, but how do you know there's no pressure on the left side? As far as I know there's only one oil pressure port and it's below the oil pressure relief valve hole, on the right, rear of the accessory case.

---

On the front of the case there are two crankcase plugs. Remove plug, install pressure gauge, start engine, and there you go. Just make sure you oil line does not interfere with propeller track. I ran my oil line back to firewall and tied gauge to motor mount so I could read it while standing behind
wing strut.

Quote:

---

Originally Posted by seilersc@charter.net

On the front of the case there are two crankcase plugs. Remove plug, install pressure gauge, start engine, and there you go. Just make sure you oil line does not interfere with propeller track. I ran my oil line back to firewall and tied gauge to motor mount so I could read it while standing behind
wing strut.

---

Ah! I was just talking with a friend who has a C-85 on his L-4 and he mentioned losing oil out of the left front plug (I didn't realize there was a right one, too). I didn't even think of attaching a pressure gauge to these. Thanks for the education.

7 pounds of pressure at idle? I’m going to make a WAG here but, is that pressure with cold oil and I’m assuming you’re using a straightweight oil like 100W?

Considering everyone else’s ideas, what about the seat forthe oil pressure relief valve? The seat is a machined surface in the accessory case and can become pretty beat up over the years. Just a guess.
JMHO, Steve.

Not sure why you would be doing an oil pressure check in this fashion to begin with. What lead you to suspect an issue and try this? I'm not sure that you are getting accurate information in this fashion, 7psi is low. I would look under the hood, pull valve covers, if you have oil all over the place then you should be good to go. Those front plugs are for an oil cooler, not pressure testing. you would get low pressure from one of them but not the other, (supply and return). There is no left/right oil feed in this style of engine. I believe the airplane tip up is for releasing an air lock that is rare but can occur, typically after an oil change after a long sitting period. Anyone else, help me on this one.

This is just a shot in the dark and you may have already solved the problem but make sure you don't have a 'sleeve' under the front plug. I bought an A65 engine once that had previously been in a Luscomb with an oil cooler (was going to put it in a Champ;/no cooler) and had the same problem. Found out there was a sleeve installed inside the chamber to force the oil to go through the cooler before going down the right side of the engine. Pulled sleeve/end of problem!! It's actually in the 65 parts book if I remember correctly. One other thing you find out on these old A65 engines is that the cam bores are getting pretty worn and lose a lot of pressure,especially at the front end. Hot and running 25-30 psi in not unusual.
Hope this helps!
Mike