Alternator STC

How to keep the Cessna 170 flying and airworthy.

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reecewallace
Posts: 165
Joined: Tue Jan 05, 2021 1:34 am

Re: Alternator STC

Post by reecewallace »

I'm on my third generator in three years. What a piece of garbage. I'll be upgrading to an alternator next time it fails.

I have a 20amp Delco Remy generator. It ALWAYS leaks.

I've had one fail completely, and the second generators drive draft stripped after only 20 hours rendering it useless.

Right now, I'm on my third generator, but it does not stop leaking. I've replaced the gasket, oil-seal, and o-ring which temporarily stops leaking but then returns.
- Reece
1956 Cessna 170b
Nanaimo, BC Canada
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Bruce Fenstermacher
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Re: Alternator STC

Post by Bruce Fenstermacher »

Reece, if you can't stop the leaking generator, how you going to stop the alternator for leaking? Same seal.
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Joe Moilanen
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Re: Alternator STC

Post by Joe Moilanen »

agree, 34 years with same generator, no problem...

Joe
4518C
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edbooth
Posts: 498
Joined: Wed Nov 24, 2004 3:03 am

Re: Alternator STC

Post by edbooth »

reecewallace wrote:I'm on my third generator in three years. What a piece of garbage. I'll be upgrading to an alternator next time it fails.

I have a 20amp Delco Remy generator. It ALWAYS leaks.

I've had one fail completely, and the second generators drive draft stripped after only 20 hours rendering it useless.

Right now, I'm on my third generator, but it does not stop leaking. I've replaced the gasket, oil-seal, and o-ring which temporarily stops leaking but then returns.
Make sure and check the gasket that seals the alt/gen and tach drive housing. Sometimes the small area between the alt/gen and tach drive developes a leak that runs down and appears that the alt/gen seal is leaking.
Ed Booth, 170-B and RV-7 Driver
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cessna170bdriver
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Re: Alternator STC

Post by cessna170bdriver »

Bruce Fenstermacher wrote:Reece, if you can't stop the leaking generator, how you going to stop the alternator for leaking? Same seal.
One reason his generators might leak is that they are most likely rebuilt (are new generators even made?) and the area of the shaft where the seal rides is worn. I had the same issue with my old generator (and starter). The latest seal on my Jasco alternator (about 1800 hours total time) went 400 hours before leaking the first drop.

Also, as a shortcut, some people cut the tach section off of the new gasket so they don’t have to remove the tach drive housing. That pretty much guarantees a leak, as that housing drains back to the generator opening.
Miles

“I envy no man that knows more than myself, but pity them that know less.”
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n2582d
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Joined: Mon Apr 29, 2002 4:58 am

Re: Alternator STC

Post by n2582d »

cessna170bdriver wrote:One reason his generators might leak is that they are most likely rebuilt (are new generators even made?) and the area of the shaft where the seal rides is worn. I had the same issue with my old generator (and starter).
Has anyone had experience using Timken’s Redi-Sleeves to repair a worn shaft? It looks like the p/n for a 0.968” diameter shaft would be 99096.
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Gary
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