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engine noise problem continues....


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I figured I would move this over to this part and start anew as the crank Plastigauged out properly...I only did the one journal, but logic dictates that if one is good, then the others should be fine...Back to valvetrain..<BR> I got ahold of the cam and lifter supplier for Buick Specialist and my machinist...take note: the 56 up type lifters SHOULD have .020-.030" preload...and since I can spin my pushrods, I am apt to believe Either I have a short cam. The 56 specs I got from them are as follows: lift- 420@ valve,duration- 196...I am going to call them later today to dbleck if there is anything else to be noted. The guy suggested I can shave the rocker stands .020-.030", but before I do this I am going to put the .015" steel shim head gaskets in and see where I get. Does anyone have an old FelPro gasket floating around so I can find out its crush before hand so I know approx. how much I am going to gain as far as the gskt....<BR> The rocker assys come into play as well as these are reman. units from B.S. also.<BR> Does anyone make adjustable rockers for these or have a pair of assemblies I could BORROW to try my theory....did put the longer pushrods in one hole and it killed the hole...valves dont close...ran it for a handful or seconds...valves didnt hit anything as far as the pistons...lots of room!!! Did compression ck...167-175 throughout...I should also pick up a couple horsies with the shim gaskets.<BR> Do any of you have any further ideas???<BR> The bottom is getting closed up, I couldnt get to the lock bolts with a wrench...I was lucky to get my fingers up there as they are facing away from me as installed. Im open for suggestions guys.....Drop me an E @ dlw29@hotmail.com<P> This is getting old real fast....<P> Thanks as always, don55

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Don,<P>Following this hoping something would "ring a bell" and I would remember something that would help you out. Feel as though the oil flow is the biggest problem you have resulting in the abnormal wear on one side. As the other appears to be fine I would think the measurements may well fall within an acceptable range even given the pre-load question (.020-.030" - I wonder if this would cause enough pounds of pressure to make turning the pushrods hard? If memory serves me correctly I could easily turn my pushrods on my '54 -- but that was 35 years ago so... See page 24 in your copy of the '55 manual). You may not have a problem necessitating machining the rocker brackets. Someone in one of the chains mentioned having adjustable push rods - if they are not too expensive that may be a better way to go.<P>I have been a bit focused on the upper end but it occurs to me that given the lifter wear from camshaft rub it would seem as though the oil is not getting to the lifters themselves (the same oil flow leaks out around the lifter running down to lubricate the individual cam lobes which seem to be running dry on one side). Don't see how this could be given that the oil gallery for the lifters was drilled in the block a long time ago and groove in the camshaft that permits enought oil to pump through for the lifters feeds both sides. This is a real mystery - WAIT - a thought that just occurred to me is the possibility of the camshaft bearing may be the problem. There should be two holes in the bearing so oil can pump to the lifter oil gallery. I don't think my thought process is faulty - the camshaft bearing is either installed with only one oil hold lined up properly or it is missing one hole (assuming this to be true since one side is okay). All lifter oil passes through the front camshaft bearing so if it is in wrong I'd carefully check the other bearings too as they may have been put in wrong as well (see diagrams on page 27 of manual to see if you don't think this may be the problem).<P>Good luck,<P>Gene

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Hi don, I havn't rebuilt a 55 motor but have a couple of ideas that might apply.<BR>Lifter Preload of .020 to .030 would be perfect, usually up to .060 is acceptable.<BR>Being able to spin them with your fingers is irrelevant.<BR>Instead of adjustable rockers what about adjustable Pushrods?<BR>Before you go machining anything don't forget about you rocker Ratio (probably 1.5:1).Example: If you machine your stands .100 you would shorten your pushrod length by .150.(Don't machine the Stands, adjustable Pushrods or Rockers is the better way to go reguardless of cost!).<BR>All of Gene Brink's Ideas shoud be explored.<BR>If its not to late (or even possible on you engine) use a drill to make oil pressure before you put the heads back on to see if oil is comming up thru the block. (and will also pump-up your Lifters). Then add the Heads and repeat to check your rocker shafts.<BR>Maybe the oiling problem will show-up that way.<BR>Good Luck.<BR>Dale

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Thanks Dale...I am gonna swap the head gaskets...been a week sice ordered too..One of the original things I was informed of and will be the absolute thing looked at and thats the front cam brg being installed wrong. As I understand it, these CAN be put in backwards as well as the wrong holes lining up as two of the holes are the same and the third hole is slightly elongated. <BR> What do you guys think of putting an original set of rockers on to see if it quiets the noise up at all....I have an opportunity which I am gonna pounce on to get a free core motor...Let me know guys...<P> Thanks, don55<P> dlw29@hotmail.com

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