Oil Leak

[blueldr]

Does anyone actually believe that;
1. Any company is currently manufacturing "antique" airplane generator specific garlock seals?
2. The seals sold by "Spruce" (Three sold per year!) are fresher stock than NAPA or a bearing house who normally deal in same?
3. You can't save more than the minimum $7.00 UPS charge on anything from "Spruce"?

[bradbrady]

George,
you need to reread my post! I had some problem with the edit side of this program and could'nt fix the 8030-3 to say 8130-3 that's the reason for the post script on my post! : But I'm totaly in agreament with you! Yea! I can get the same part number, parts from Federated! But will not use them becuse the paper work won't let me! I know what BL is saying and I agree with him, but the paper work dosn't come with the federated products! And I need that paper work to keep my self from visiting my local FSDO!
brad

[GAHorn]

George,
you need to reread my post! I had some problem with the edit side of this program and could'nt fix the 8030-3 to say 8130-3 that's the reason for the post script on my post! : But I'm totaly in agreament with you! Yea! I can get the same part number, parts from Federated! But will not use them becuse the paper work won't let me! I know what BL is saying and I agree with him, but the paper work dosn't come with the federated products! And I need that paper work to keep my self from visiting my local FSDO!
brad

I took the "liberty" of correcting your typo for you... hope you don't mind... as for the post script...I'm not sure what you mean... but I appreciate your diligence and correctness insisting upon genuine approved parts/materials. YOU THE MAN!

[wa4jr]

My generator problems have transferred from electrical to mechanical involving a persistent oil leak so I'm taking up the issue here instead of under "generator problems". My idea of changing from Permatex aviation sealer to a copper-bearing sealer and letting the engine sit overnight with no oil has not solved the problem. In fact, the problem is much worse now I watched the generator flange during the ground run this morning, and saw the leak starting at the top of the flange as a big black blob, and then trailing down both sides of the flange. The tach drive housing is clean. This is the third time I've removed the gen trying to repair what in theory should be a simple problem. Since this leak always develops at the top of the generator flange, I put an especially heavy coating of coppercoat in this area to include both sides of the gasket and both flange surfaces. I see the re-assuring "squishout" of surplus sealer, but the oil just pushes right past the sealer like it wasn't even there. The only thing I have not tried is cleaning the gasket/flanges and reinstalling with no sealer of any kind. Or I can use a more aggressive type sealer, like the contact cement one fella used, but you should not have to resort to such extreme measures to get a simple gasket to seal. I go in for annual next week, and may let my mechanic struggle with the problem, but it makes me so darn mad that I can't repair such a simple problem I've never in all my years of engine work seen such a leak as this generator flange leak. I swing from the end of my rope and await advice from those that have had this experience before.

[N1277D]

We had a persistant oil leak on the Franklin, under a valve cover. We ended up using a product manufactured by permetex; a red goo type of mixture that did not harden. We used a surface prep manufactured by them to clean the oil off/out of the metal surface then applied the goo. It was pricey but it worked. I have forgotten the name of the stuff. It might be listed on their web page or product catelog.

I believe we found it in their product catelog. There were numerous surface preps and sealants listed depending on temperature and if the metal was clean or if it had an oil film on the surface. If I recall correctly any aluminum surfaced needed the surface preped other wise a thin film of oil prevented a sealed contact with the gasket sealer to the metal.

[wa4jr]

Since the oil leak is so bad that I don't want to risk the 10 minute flight to the mechanic shop for annual, I am going to try....for the 4th time to remove and reinstall my generator with an oil tight seal. Have not decided whether to use gasket sealer or not this time. Came closest to sealing the leak with the Permatex aviation sealer. If I use this stuff again I will let the airplane sit for two days with no oil to give the sealer time to firm up. I've made it a point to clean all the flanges with brake cleaner to the point where my fingers hurt from rubbing. This last time I even carefully inspected the entire flange area with mirror and bright light for the slightest speck of "stuff" that may prevent a good seal. The flanges are so clean I can eat off of them! I know the leak is between the gasket and the generator flange, not between the case and gasket. I'll check the gen flange with a straight edge to eliminate a warped surface here. There is no leak with the engine static, only when the engine is running, and worse when at higher RPM. Knowing I have a lot of ring blowby, I thought the case was pressurizing...but my case vent is wide open. Here I go again...if a funkhana is ever held in which one event is a "generator quick change", I've got it all sewn up

[GAHorn]

John, I posted a msg to your oil leak under the "IO-360" discussion. It goes like this:
If you absolutely CERTAIN its the gasket leaking... and not the gen seal....
Consider using 1/16" thick rubberized cork gasket sheet (available from NAPA) and Permatex No. 2. This is the magna-carta of oil sealing gasket material.

Keep in mind that at the 12 o'clock position of the generator, at the accy case, theres a hole that accomodates the driven gear of the oil pump. This is why that gasket MUST NEVER BE CUT, because it will leak. It WILL!
Use the rubberized cork sheet to make a complete gasket and use the Permatex, and I'll bet a case of St. Pauli Girl your problem will disappear.

[wa4jr]

Hey George, I see your not bettin a case of Guiness on that idea...that worries me somewhat I'll try almost anything at this point, but what really nags me is why this leak has decided to start with the installation of a new generator??? Why did it not start the other times I had my old generator off...why not last summer when I had the accessory case off for the B&C starter? Something has changed and the only change has been a new/rebuilt generator that came from Kelley Aerospace. With a leak as large as I have, I think mechanical problems such as a damaged mounting flange, yet no damage is apparent. I like your idea of a NAPA airmotive gasket, but I do wonder about how well that 1/16" material will hold up under the heavy leveraged load of the generator? Will the mounting nuts need to be retorqued as the rubber impregnated gasket compresses and settles? Perhaps Continental has a SB on this problem that I have not seen? If the original gaskets are not up to the job of sealing the generator, why are they still sold? I'll make a trip to NAPA in the morning and try your trick along with letting the engine sit with no oil for a couple of days to allow the Permatex to set up. This stuff needs to be in a manual or SB somewhere so we don't waste time using materials and techniques that are prone to a high failure rate. BTW, the shaft seal is dry as a bone...until it is drenched from the flange leak above it. I sense more adventure to follow

[GAHorn]

Once the fiberlock/nylock nuts are tightened the gasket should not compress further under the weight of the generator. Careful to torque all nuts sequentially...so that one isn't tightened substantially more than any other at any time. It'll be easy to crack that tachdrive housing if you tighten one down, then go to do the others. The gen won't much care.

[wa4jr]

With the removal of my generator for the fourth time, I finally have forensic evidence of my oil leak. The last type of sealer I used, the coppercoat stuff, left a definite indication of an oil track running from the lower "notch" at the top of the gasket on the generator flange side straight up to "daylight" at the top of the generator flange creating the monster leak. Looking at the design of the gasket and flange, the big problem is the big hole in the generator mounting flange on the accessory case. This hole removes 90% of the sealing ability in this area. I notice the factory generator gasket has a "half moon notch" at the lower surface of the top portion of the gasket, which removes any ability for the gasket to seal along the lower edge of the top flange. The only area in which there is full flange and gasket present for proper sealing compression is a very narrow strip at the very top of the generator mounting flange just under the tach drive housing, and this is why I have a leak. The remaining sealing area just isn't enough. I'm cutting a new gasket out of 1/16" rubberized fiber gasket material, and will eliminate the "half moon notch" so as to regain proper flange compression and sealing along the lower edge of the top portion. I'm counting on the thicker more pliable gasket along with a thin coating of Permatex sealer and proper set time to do the trick. With such a poorly designed generator flange on the accessory case, along with the "let's make sure it leaks notch" on the factory gasket, I'm surprised only 170C and myself have experienced these gusher oil leaks.

[170C]

Just as a note, when I replaced the factory gasket with the NAPA gasket material, I did not use any sealant such as Tite-Seal or Permatex and did not have the leak after doing so.

[wa4jr]

Well, George you can keep your case of St. Pauli Girl beer! I can report success with the oil leak battle thanks to you. All the NAPA stores were closed for the holiday, but I did find some rubberized fiber gasket material in the proper thickness at Pep Boys, cut my gasket based upon the original with the exception of no "half moon notch", put on a couple of coats of Permatex aviaition gasket dressing, put it all together and let is sit overnight before adding oil. Engine passed the oil leak check today with a ground run and half-hour test flight. I'm back to my regular oil leaks now I'll have to admit that the joint does not look professional as there is a good bead of "squished out" sealer along the flange edges...but darned if I care if that is what it takes to seal the "Mt. Vesuvius oil leak" I had. Next time I have the generator off, I'll make my own gasket again, but not use so much sealer...or maybe none at all for a cleaner installation. A shame it took me four or five (lost count) tries to get my generator to seal...I still think there should be a service bulletin on this and a change of gasket material and design.

[GAHorn]

Well, George you can keep your case of St. Pauli Girl beer! I can report success with the oil leak battle thanks to you. ....

Dang! I knew I'd worded that incorrectly! I meant to say something along the lines of me getting a case of St. Paul Girl!