I pulled the cowling off the Val on Saturday morning to change spark plugs, and for the first time, I saw evidence of a minor oil leak. There was a thin line of oil (probably not more than a few drops in all, but it really spreads!) across the inside of the top cowling, behind the baffles, and above the accessories. I checked everywhere for a source, but couldn't find an actual drop. The obvious thing was that it seemed to be a line that had been "flung" from the SD-8 alternator that is mounted on my vacuum pump pad. I cleaned everything thoroughly, and ran another couple of hours on Sunday, and sure enough, I had another thin line. Still there.
I wrote to B&C (the makers of the SD-8) to see if they thought oil could be coming through the alternator itself, and the response was that yes, if the oil was getting past the oil seal in the vacuum pump drive, it could migrate up the shaft, and then be flung by the rotating housing. This sounded exactly like what was happening. My next question was "could I change the seal without removing the accessory case?"
For this, I sent a note to Mahlon up at Mattituck. I got another very fast response saying that the seal is not a problem to replace - it is actually in the vacuum pump drive adapter, and if I pulled the SD-8, the adapter slides right off. He then offered that if I took it off and sent it to him, he'd take care of replacing the seal and send it right back. Really nice! Of course, that, would necessitate the Val being out of service for several days (even with overnight shipping), so I asked how hard it would be for me to change the seal in the field. "Not a problem...pry the old one out, press a new one in" was the response "I'll drop one in the mail for you!"
So once again, as I have found many times, great response from the vendor's that support our avocation! Good technical info, and great customer support! I assume I'll get the seal in a couple of days, which should make everyone in Texas rejoice, because then I'll want a rainy day to do the change-out, and the weather being what it is, that will assure clear and sunny for weeks on end....
I'll report back on this thread on the results of this minor surgery...
I wrote to B&C (the makers of the SD-8) to see if they thought oil could be coming through the alternator itself, and the response was that yes, if the oil was getting past the oil seal in the vacuum pump drive, it could migrate up the shaft, and then be flung by the rotating housing. This sounded exactly like what was happening. My next question was "could I change the seal without removing the accessory case?"
For this, I sent a note to Mahlon up at Mattituck. I got another very fast response saying that the seal is not a problem to replace - it is actually in the vacuum pump drive adapter, and if I pulled the SD-8, the adapter slides right off. He then offered that if I took it off and sent it to him, he'd take care of replacing the seal and send it right back. Really nice! Of course, that, would necessitate the Val being out of service for several days (even with overnight shipping), so I asked how hard it would be for me to change the seal in the field. "Not a problem...pry the old one out, press a new one in" was the response "I'll drop one in the mail for you!"
So once again, as I have found many times, great response from the vendor's that support our avocation! Good technical info, and great customer support! I assume I'll get the seal in a couple of days, which should make everyone in Texas rejoice, because then I'll want a rainy day to do the change-out, and the weather being what it is, that will assure clear and sunny for weeks on end....
I'll report back on this thread on the results of this minor surgery...
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