No Oil Pressure

[alwaysoar]

Thanks for all the replies to my initial thread. I wonder how an engine like mine with only about 1800 TT could have the amount of wear in the accesory case to cause an oil pressure problem. Unlike what Tim just described, once I get oil pressure and run the engine on a regular basis (one or twice a week) I don't have a problem. I suppose that means the wear isn't as bad as some others.

[Robert Lees]

1800 is the TBO for most small Continentals. If the accessory case has not been restored in the interim, then it is of no great surprise.

[alwaysoar]

It was overhauled at 1100 hours, now has 700 SMOH. Of course that doesn't mean the accessory case was touched. Even so that doesn't seem like much time for that kind of wear.

[captjon]

Accessory Case Wear

Keep in mind that we are dealing with a set of steel pump gears and their shafts, all spinning constantly in soft aluminum. I am not surprised that the cases show the wear that they do. Without the constant bath of oil around them they really would wear!

The fix by Drake Air puts in bronze bushings where the shafts go into the acc. case....a much better bearing material. You still have the possibility of wear in the hole in the cover plate though as I don't think they bush that and the plate is soft aluminum. I think it's kind of amazing they last as well as they do, considering the design. The original engineers at Continental probably didn't think we would be even discussing this issue some sixty years later, never mind rebuilding these little gems!

Take a look at the camshaft journals someday............same thing here, steel or cast iron camshaft riding directly in the aluminum crankcase with no bearings between the two..........

Cheers,

[alwaysoar]

That begs the question, is there wear in the camshaft journals that will require a fix? Is there a fix?

[Goneflyin]

I put one of the Fresno A/F reconditioned cases on my motor this time last year with the original gear set, they still had the machining marks on them and no more putting the tail on a ladder to prime the pump.
I built quite a few Honda bike motors back in the 70's and 80's and I can't remember any of the inline fours that didn't run the cam right in the aluminum head without bearings, have to see if they last another 40 years. Someone mentioned awhile back in the group that after the motor starts and the pressure is up to bring it up to a 1000rpm so the rods will throw some oil on the lobes. When we did the accessory case last year we looked at the cam and it looked good, so maybe it helps, time will tell.

[larrysmith1016]

Re: No Oil Pressure

[QUOTE=captjon]Steve:

Gary is correct on the high cost at Drake Air. They do a fine job, but get a lot for their work. My friend Marcel had his C85-12 accessory case done by them last year and all is well now. He had the same problem basically. He would have good pressure initially when started from cold, but if you turned it off, and started again there would be none. Lifting up the tail would get it back. Not exactly what I want under my cowling!

This all happenned before I started my new business, T-Restore.biz, LLC. Now I could help him out as I have found a source of Continental O-200 accessory cases for less than he paid for his repair. The C85-12 accessory case is the same
*******************

Hallooo, Cap. Jon.:

I just talked to Captain Woody who advertises under the Continental Engines heading in TAP, and he says he sells reworked accessory cases for $350. I bought one from him some time back and it had new bushings installed in the shaft bearings for both pump gears and a new cover plate, which also has a bearing for the pump drive. When I installed the pump and cranked up the engine we had instant and xlnt oil pressure.

I have another rear case with bearings clearances out of limits by several thousandths, but the pockets and gears mike to be in limits. Woody says he is in Texas at the time and is having his work done by ECI, San Antonio.

I'm thinking of buying two from him, one for me and one for a friend who is overhauling his Flybaby engine.

Good to be back, btw. I've been awol for over a year and hope to fly to Alliance in summer and camp out with the WV and OH lizards along the way.

[paulp]

Re: No Oil Pressure

Howdy Larry,

Your right about Drake, however, you get what you pay for. A great deal will depend on wether your assc. case is Magnesum or Aluminum. Mine is Mag. and not everyone will reman. them. I think that there are only 3 or 4 places in the US that does mag. work and the price is high. I had my main case and the assc case done at the same time and the assc case was more than the main case. But, they magnafluxed it, refaced the mounting surface and machined the oil pump housing and brought it to fact. specs. I have over 150 hours since the major and the oil pressure is 35lbs at idle or 2475 rpm. I'm a happy camper.

[M Towsley]

Re: No Oil Pressure

Larry,

Did Woody move to Texas, or is he just wintering there? If he moved, do you have a new number for him? Haven't seen an ad for him in TAP lately. Thanks!

[larrysmith1016]

Re: No Oil Pressure

Larry,

Did Woody move to Texas, or is he just wintering there? If he moved, do you have a new number for him? Haven't seen an ad for him in TAP lately. Thanks!

He's still in Texas but will be back in WI soon, he said. I got his number out of the 1st March issue of TAP and would give it you but don't have the TAP here. It's an 800 number.

Anyway to answer another question posed, I didn't make any comment about Drake; I think that was Captain Jon. I have no experience with them.

The rebuilt accessory case I bought from Captain Woody, which was a dandy, was indeed magnesium. The pockets were fine; it was the bearings which needed rebuilt, with bronze bushings installed. IIRC, Woody said it had been rebuilt by Darryl Bolduc in MN. Only thing I had to do for it was get rid of some corrosion, magnadyne it, and paint it. It worked like a charm and gave good oil pressure. I like those magnesium cases; they're light and durable. But I have one that's warped so bosses for the mags are cocked inward so that the mags butt up against each other. Otherwise it's fine.

I need bushings installed in the bearings on the aluminum one I'm working with now. You can use a feeler gauge and find if the pockets are worn out of limits. It seems to me that what wears them out of limits in the pockets is too much slop in the bearings. If the gears track true, they stay in their place and don't scuff up against the case.

Also what I usually do is polish the surfaces of the cover plate by using a thick piece of glass and sanding with 320 grit. Machines that little sucker right down to precision.

Good to see y'all again.

[Len Petterson]

Re: No Oil Pressure

Do I have problem brewing in my A 65?
On start up 40 psi and running I get 30 The oil pressure commes up rigth away so no problem there. It has been ocations where at idle, 500 rpm, the oil presure is almost 0, minimum should be 5 psi. adding some Rpm and it comes back up. I run Shellw100 in the sommer and w80 in the cold wheater.
The oil pressure has droped somewhat sence I got her. it used to run at 32 to 35 psi.
Len

[Ragwing nut]

Re: No Oil Pressure

That begs the question, is there wear in the camshaft journals that will require a fix? Is there a fix?

The front cam journal IS the weak link in small Continental cases. That is where all the wear is and if it is beyond limits, oil pressure will be low or will follow the throttle.

$600 to repair a rear case is rediculous. Divco charges that overhaul the main case. Divco will also repair rear cases as well for alot less. Never sent them a mag rear case for repair yet, only aluminum.

Mike

[paulp]

Re: No Oil Pressure

Howdy Mike,

Your right-$600. is ridiculous. What is even more incredulous is that Drake will not repair a mag case for that amount!!!!! Mine was over $600. but they did a first class job. Don't bother to send a mag case to Divco-they will sub it to Drake. If you have a magnesum case your pretty limited on the number of places that will inspect and repair it. Just remember, it's not real money-it's airplane money!!!

[Marcus Bates Jr]

Re: No Oil Pressure

Some of the FBO's used to store the airplanes on their nose, prop resting in a fixture, to save room.....

[Len Petterson]

Re: No Oil Pressure

I went up for a hour today Airtemp 33F max oil temp 150F oil pressure stayed at 35 psi @ 150 degF.
Up from 30 on my last 2 hr. Dirt under the relife valve? iIt was suggested by my AI. This engine has 1716 hr sence new and only 2 cylinder has been of it.
Still pulls her to 90 + Mph at 2250 rpm. It passed corrosion in spection in 99.
Len.