hey guys...ive been working on my 303 like crazy trying to get it together. got my clearance issues with the adjustable rocker arms fixed. i had everything together then realized i had forgotten to put the spring loaded plunger in the cam shaft. now before i did this (without the plunger in front) it turned over by hand ok with a foot long screw driver wedged in the pully. so i took it appart. put it back together now there is mega resistance to the point it takes tonnnns of effort to even get it to turn a little. the back cap is as far back as it should be. is this the issue? i cant see it being anything else since it turned ok before this. could it be the rocker arms are not adjusted right? or maybe im lost. when i bought this motor it was rebuilt a while ago with cool parts but it did not have the spring plunger in like my 324. i hope im just stupid or am i missing something here? thanks in advance. hopefully i can have it running again by the weekend! keith
First thing I would check----Pull the intake off and valley pan. Lool to see if the cam got pushed foreward by the distributor gear when you turned it without the spring pin installed. Maybe a lifter is about slipped off on edge of a cam lobe. Hope you didn't chew anything up.
ive got the cover off and the cam is definatly too far towards the rear of the engine. much more than it was before i put the pin in the front. is there any difference between the 303 and 324 pins? and yes, hes been one of my heros this far along.
as far as I know all the cam buttons are the same except for the early 303 having a smaller diameter shank, if you used a 324 cam button and it went in the end of the cam you should be good. you say the cam is too far back? I don't see how it could, it would be beyond it's thrust surface and the chain would be hitting the block
there's a big'ol freeze plug at the other end of the cam,you'd have to remove the transmission to replace it if it fell or was pushed out. you better pull the cam out and shine a light down there and see if the plug is in place.
the engine is appart on the stand. its all in place...just looks a little far back to me. its within spec but not centered on the lifters. i took the cover off took the pin out and it spins twice as easy with it out. how much force should i be using to turn the motor over by hand with everything installed. no spark plugs of course. thanks for the advice guys, its helping by the way, i almost forgot. the cam is an aftermarket 3/4 from the early 60s. could that have anything to do with how the lobes and lifters line up. my 324 they are dead nuts center with each other. this 303 its more to the back.
my 303 lifters sit a lil off center as well... so does the only other one ive ever seen under the valley cover of... from what i know thats normal
it makes sence really, i could also be nuts thinking the 324 is centered and i wouldnt doubt im nuts haha. by the way todd, wicked car!
the lifters are supposed to be off center, so the cam rotates the lifters in their bores. what is the diameter of the hole in the end of your cam that the cam button goes in? as compared to the button's shank diameter? if the button fits in the hole the spring should be easily depressed with relatively little thumb pressure. sounds to me like you have a '49 or '50 cam with the smaller hole for a smaller cam button and you are jambing it with a later larger button.
yea...the off center thing was a brain fart i guess. realized that after haha. the button goes in and compresses like a charm. with it in you can see the pressure its putting on the front cover after half a rotation when i take it off and look at both the cover and button. my wonder is...when i bought this motor it didnt have the button in it. and as a result the gears were worn like mad. something doesnt add up to me here. the button is defintatly the right one 100% fits an extra 324 cam the same as the one in the 303 were talking about. seems as if this guy gave up because he was in the same situation as me. do you think i could file down the front cover where the button rides to give it some clearence. i know i shouldnt have to even think of doing that but nothing is adding up with this. and the fact the original builder decided not to put the button in also makes me wonder.
Idea! put the button in and bolt the cover on but leave it loose,2-3 turns of the bolts. Try turning the engine over ,if OK tighten up the bolts a half turn try again. If it starts getting tight as you run the bolts in sounds like not enough clearance between cam and cover.
Try Ross Racing Engines in Niles Ohio phone is 330 544 4466 Ask for Ross .Afternoons are best time .He specializes in Oldsmobiles
From gasket surface of front cover to cam button contact is 1 7/8 inches. Button is 1 3/4 inches overall, diameter of small end is 3/8 inches. Small diameter where it goes into cam is 7/8 inches long. Free length of spring is 1 inch. Make sure there is not shit in the hole----of the cam that would bind up the depth of the pin entry.
i was talking with ross i believe both about this and having a 324 built. very nice and knowledgabe guy. i checked the specs on the button and everything but the spring is the same. the length is 1 1/16th. i only asume its strectched that 16th over time but compresses the same. theres nothing in the hole at all. but once i put the front cover on its tight as can be and takes some effort to turn the motor by hand.
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