Oil Pressure relief spring
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
- Bill Hart
- Posts: 455
- Joined: Tue Aug 23, 2005 2:04 pm
Oil Pressure relief spring
Can some one tell me the part number and a source for a new oil pressure assembly?
- Bruce Fenstermacher
- Posts: 10422
- Joined: Tue Apr 23, 2002 11:24 am
Bill if your looking for the spring it's #637083 the plunger is #21114 and the acorn nut is #21113.
I bought the spring for $6.13 from http://www.aircraft-specialties.com/. They have the plunger for $44.53 they don't seem to have the acorn nut
CessnaParts.com http://www.cessnaparts.com has all three at the following prices: #637083 @ $9.94, #21114 @ $61.07 and #21113 @ $91.54
Preffered Airparts http://www.preferredairparts.com has 117 used nuts #21113 and 12 #21114 plungers and they generally sell new parts for half list and used parts even cheaper
I bought the spring for $6.13 from http://www.aircraft-specialties.com/. They have the plunger for $44.53 they don't seem to have the acorn nut
CessnaParts.com http://www.cessnaparts.com has all three at the following prices: #637083 @ $9.94, #21114 @ $61.07 and #21113 @ $91.54
Preffered Airparts http://www.preferredairparts.com has 117 used nuts #21113 and 12 #21114 plungers and they generally sell new parts for half list and used parts even cheaper
CAUTION - My forum posts may be worth what you paid for them!
Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
- cessna170bdriver
- Posts: 4115
- Joined: Mon Apr 22, 2002 5:13 pm
Oil Pressure Relief Valve Spring: part number 637083 .
Oil Pressure Relief Valve Plunger: part number 21114 .
Try entering the part numbers at Premier Aviation.
You can also try Superior Air Parts.
Miles
Oil Pressure Relief Valve Plunger: part number 21114 .
Try entering the part numbers at Premier Aviation.
You can also try Superior Air Parts.
Miles
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
- GAHorn
- Posts: 21295
- Joined: Fri Apr 12, 2002 8:45 pm
WHAT? You forget to recommend Premium Aircraft Parts?cessna170bdriver wrote:Oil Pressure Relief Valve Spring: part number 637083 .
Oil Pressure Relief Valve Plunger: part number 21114 .
Try entering the part numbers at Premier Aviation.
You can also try Superior Air Parts.
Miles

'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.

- Bruce Fenstermacher
- Posts: 10422
- Joined: Tue Apr 23, 2002 11:24 am
- cessna170bdriver
- Posts: 4115
- Joined: Mon Apr 22, 2002 5:13 pm
- cessna170bdriver
- Posts: 4115
- Joined: Mon Apr 22, 2002 5:13 pm
Using a new spring and plunger of the above part numbers, with the original cap (along with a major overhaul), my O-300A’s oil pressure indicates between 53 and 57 psi (Phillips 20W50), depending on temperature. The gauge pics were taken at 0.2 and 0.5 SMOH, respectively.lowNslow wrote:Are these part numbers for the O-300 or the C-145, which seems to require a lower oil pressure?



Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
- cessna170bdriver
- Posts: 4115
- Joined: Mon Apr 22, 2002 5:13 pm
- lowNslow
- Posts: 1535
- Joined: Mon Apr 22, 2002 4:20 pm
Same here, but according to everything I can find it should be 30-45 psi for a C-145.cessna170bdriver wrote:Using a new spring and plunger of the above part numbers, with the original cap (along with a major overhaul), my O-300A’s oil pressure indicates between 53 and 57 psi (Phillips 20W50), depending on temperature. The gauge pics were taken at 0.2 and 0.5 SMOH, respectively.
Karl
'53 170B N3158B SN:25400
ASW-20BL
'53 170B N3158B SN:25400
ASW-20BL
-
- Posts: 507
- Joined: Sat Oct 18, 2003 9:07 pm
Karl,lowNslow wrote:
Same here, but according to everything I can find it should be 30-45 psi for a C-145.
I don't have the overhaul manual and parts catalog in front of me, but I believe the specs and the oil pressure relief part numbers are the same for the O-300A and the C-145 (better double check me on that). I had questions about my high oil pressure in my O-300A and this is the answer I got http://cessna170.org/phpBB2/viewtopic.p ... l+pressure
Makes sense to me.......
John
N2865C
"The only stupid question is one that wasn't asked"
N2865C
"The only stupid question is one that wasn't asked"
- Bill Hart
- Posts: 455
- Joined: Tue Aug 23, 2005 2:04 pm
Check out this thred high oil press
http://www.cessna170.org/phpBB2/viewtopic.php?t=1246
http://www.cessna170.org/phpBB2/viewtopic.php?t=1246
- lowNslow
- Posts: 1535
- Joined: Mon Apr 22, 2002 4:20 pm
Both of these threads indicate an O-300. The TDC indicates a oil pressure of 30-40 psi for both the O-300 and C-145. The Operators Manual states a oil pressure of 30-45 psi for the C-145 and 30-60 psi for the O-300. These are old sources - the TDC is dated March 1974 and the Ops. Manual is undated is undated but seems to be around the same vintage. I am just looking for some official documentation with updated allowable oil pressures if one exist.
Karl
'53 170B N3158B SN:25400
ASW-20BL
'53 170B N3158B SN:25400
ASW-20BL
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