Hey guys, I recently did a top end rebuild of my 455 engine with new cam and lifters timing chain, gears... etc, car seems to run great, at idle have good oil pressure when warm about 25lbs, when running up to 60 Lbs. I replaced the pump when I did the rebuild. Question is at startup for the first couple of seconds while the pressure builds I get some rapping but once it pumps up , no noise or knocking. Quiets down pretty quick I think its mostly lifter noise but it there a check valve or something that i missed that can hold oil pressure up between startups or is this something I need to live with? This is the first 455 I have ever had so not really sure what to expect. Thanks
Some of the hydraulic lifters out there do this (mine have for 11+ years now); I should have spent the extra 20 or so for something not hecho en Mexico. I gave up worrying about them years ago.
Sometimes, that is the result of a weak anti drain back valve. Not sure what kind of filter you are using, but maybe you could try another. The Wix filters are pretty good in that respect. Due to the position of our oil filters, a certain amount of drain back is unavoidable. It takes a few seconds to fill the filter and galleys when the engine is started.
Of course it is! ill see if I can get a Wix online and give it a shot Thanks guys I’ll let you know how it goes
WIX 51258, 4.25 at Rockauto, https://www.rockauto.com/en/moreinfo.php?pk=360607&cc=1379763&jsn=451 https://www.rockauto.com/en/catalog/buick,1970,gs+455,7.5l+455cid+v8,1379763,engine,oil+filter,5340 Or NAPA Gold 1258. https://www.napaonline.com/en/p/FIL1258
Get rid of the Fram filter use a Wix, or AC ANYTHING but Fram, switch to 10/30 oil if your not using it yet and report back.
Was there a break in period for the valve train? Have read & told not to let engine idle when you first run the car after a new cam and lifters.
If you have excessive bleed down of some lifters, they will make noise until they fill with oil. Quality control of lifters has been lacking in past years.
I don't install ANY hydraulic lifters without taking them apart & cleaning them. You would be surprised if to see how much debris is in them from the manufacturing process.
