Oil leaks
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
- GAHorn
- Posts: 21295
- Joined: Fri Apr 12, 2002 8:45 pm
The tool (Burroughs 4915A) and less expensive copies(about $35 I think is what I paid for mine) are sold by El Reno 800-521-0333 (and others) and the repair can be done in situ. All you must do is remove the rocker covers, rocker arms, and pull out the pushrods. (Do this carefully so as not to extract the tappets in case you have the old style. This may be done by rotating (twirling) the pushrod until it releases from the socket of the tappet. Another method is to apply low-pressure air to the upper end of the pushrod, injecting air thru the hollow pushrod to "break" the oil-suction at the tappet.)
Keep the pushrods in order, so they can be reinstalled exactly in the same location as they came out.
Don't get carried away with the tool. It only takes a little bit to fix the leak. (Similar to torqueing a bolt...just because a little torque is good...doesn't make a lot of torque better.) You don't want to overdo it.
Keep the pushrods in order, so they can be reinstalled exactly in the same location as they came out.
Don't get carried away with the tool. It only takes a little bit to fix the leak. (Similar to torqueing a bolt...just because a little torque is good...doesn't make a lot of torque better.) You don't want to overdo it.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

- GAHorn
- Posts: 21295
- Joined: Fri Apr 12, 2002 8:45 pm
As for the tappet (lifter body) issue, see:
http://cessna170.org/phpBB2/viewtopic.php?t=3027
http://cessna170.org/phpBB2/viewtopic.php?t=3027
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

- GAHorn
- Posts: 21295
- Joined: Fri Apr 12, 2002 8:45 pm
There may be an issue with the center cylinders (nos 3&4) removing their rocker arm shafts. Sometimes the cylinder base nuts must be loosened to get enough clearance to slide the shaft out past the adjacent cylinders.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

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