Cadillac & LaSalle Club Discussion Forum

Cadillac & LaSalle Club Forums => Technical / Authenticity => Topic started by: 49 Caddy on April 06, 2024, 01:31:33 PM

Title: 49 331 cu. in. aftermarket pushrods
Post by: 49 Caddy on April 06, 2024, 01:31:33 PM
  Re-build kit I purchased has been pretty much on the money for parts and such, however, the replacement push-rods are shaped a little different on the ends and are approx. 3/16" longer.  Don't really want to shim the rocker arm shafts, so any other alternatives.  Use a different supplier?
Title: Re: 49 331 cu. in. aftermarket pushrods
Post by: Jay Friedman on April 06, 2024, 04:37:59 PM
I would try a different vendor. I suggest Terrill Machine, DeLeon TX or Egge Machine in California (if you didn't buy your rebuilding kit from either one of these.)
Title: Re: 49 331 cu. in. aftermarket pushrods
Post by: 49 Caddy on April 06, 2024, 06:11:34 PM
  Can't remember who it was purchased from, but I think it came with a mild cam.  Does that matter?
Title: Re: 49 331 cu. in. aftermarket pushrods
Post by: 49 Caddy on April 06, 2024, 09:14:54 PM
  May have answered my own question.  Compared the old lifters to the new, and the new are shorter.  About the same amount the new pushrods are longer.  Any input?
Title: Re: 49 331 cu. in. aftermarket pushrods
Post by: The Tassie Devil(le) on April 06, 2024, 09:18:42 PM
Are the new cam followers Mechanical?   As against Hydraulic?

Bruce. >:D
Title: Re: 49 331 cu. in. aftermarket pushrods
Post by: Jay Friedman on April 06, 2024, 10:51:06 PM
Quote from: 49 Caddy on April 06, 2024, 09:14:54 PMMay have answered my own question.  Compared the old lifters to the new, and the new are shorter.  About the same amount the new pushrods are longer.  Any input?

Put it together and see if it works.
Title: Re: 49 331 cu. in. aftermarket pushrods
Post by: 49 Caddy on April 07, 2024, 07:23:13 AM
  I was thinking the same thing, Jay.  I might be over thinking things.  A professional Speed Shop did the machine work and assembled the short block for me.  I'm basically just adding the heads and top end.  Just wanting everything to go right.  Been 50 yrs. since I last got inside a motor.  Thanks for responses.
Title: Re: 49 331 cu. in. aftermarket pushrods
Post by: Jay Friedman on April 07, 2024, 08:41:37 AM
If the pushrods end up being too long and one or more valves doesn't close completly, you can experiment with shims or washers of different thicknesses under the rocker arm brackets.  You'll have to do that along with compression tests, until you get it right. As I think I mentioned before, this happened to my own motor when rebuilt some years ago.
Title: Re: 49 331 cu. in. aftermarket pushrods
Post by: Bob Kielar on April 07, 2024, 02:12:30 PM
There are adjustable push rod length checkers for about $20.00 thru Summit racing.

Keep Cruzin,
Bob Kielar
Title: Re: 49 331 cu. in. aftermarket pushrods
Post by: Jim Miller on April 08, 2024, 10:28:03 PM
I had to put new push rods in my '49. The new ones were a touch longer. The difference was very small but it was enough to affect how the engine ran. As Jay mentioned, I used shims on a trial and error basis till we got it just right. Engine now runs great.
Title: Re: 49 331 cu. in. aftermarket pushrods
Post by: PHIL WHYTE CLC 14192 on April 09, 2024, 01:12:21 AM
Put a new pushrod and lifter together and an original lifter and pushrod and measure the overall length and compare. Make sure neither lifter is stuck in the down position (more likely with the old one I suppose).