Click on image for the lowdown. 
====
| | | Forums66 Topics128,035 Posts1,055,445 Members48,422 | | Most Online14,466
Apr 26th, 2026 | | AD Chevy Trucks  Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
Lots of work on Brad's part ... pure enjoyment (and references) for you!
| | THANKS!
For helping keep this great
old truck web site
on the Internet for over 30 years! and not clogged down
with Ads!  Again, thanks!
| | | | Joined: Mar 2013 Posts: 217 'Bolter | | 'Bolter Joined: Mar 2013 Posts: 217 | just starting to assemble my 270 GMC and i pulled the oil pump apart to clean it. and i got to thinking about the relief spring, back in the old days we use to stretch them or shim them a little with the idea it would boost oil pressure. i have some AN washers that are .06 thick and fit perfectly under the spring good or bad idea???
Jay D. | | | | | Joined: Mar 2014 Posts: 4,479 Moderator, Electrical Bay | | Moderator, Electrical Bay Joined: Mar 2014 Posts: 4,479 | Generally shimming the spring will not help with low oil pressure at idle...at least from what I've seen. It could help with oil pressure at higher rpms however...but how much? You're sort of guessing. Please don't stretch the spring. Not a good scheme. If you could find a new spring that might be better.
~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
| | | | | Joined: Jan 2022 Posts: 2,437 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,437 | Just FYI, I tested a 270 oil pump 10 or so years ago and found the pressure relief valve started dumping at 57 psi.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: Feb 2004 Posts: 29,750 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,750 | I used to do a classroom demonstration on how to stretch a spring- - - - -grab both ends of the spring with vise grips- - - - -stretch it to 3 times its original length- - - - -use a pair of wire cutters to cut it into pieces 1/2" long- - - - -then buy a new spring!
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: May 2015 Posts: 11,004 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 11,004 | I used to do a classroom demonstration on how to stretch a spring- - - - -grab both ends of the spring with vise grips- - - - -stretch it to 3 times its original length- - - - -use a pair of wire cutters to cut it into pieces 1/2" long- - - - -then buy a new spring! Good advice. LOL!
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | |
|
|
