Thread: Big block valve train clatter

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Not sure I follow you Pat, about drilling the plugs in the front and what keeps oil from moving past to the dist hole?

Originally Posted by bigred1957

Not sure I follow you Pat, about drilling the plugs in the front and what keeps oil from moving past to the dist hole?

well they are small under 060 see them on this sbc i built? the dist is part of the oil galley if the bock hole is big or dist is small some oil will pass like jerry said .MSD grooves there dist for Orings to help some and helps put oil on dist gear they drill a small hole that sprays oil on the gear with the Orings on that make s the oil shot circuit work that MSD use

Originally Posted by pat mccarthy

well they are small under 060 see them on this sbc i built? the dist is part of the oil galley if the bock hole is big or dist is small some oil will pass like jerry said .MSD grooves there dist for Orings to help some and helps put oil on dist gear they drill a small hole that sprays oil on the gear with the Orings on that make s the oil shot circuit work that MSD use

I see, so by what your saying, my distributor could be the next place to look? It is aftermarket but I haven't looked into it yet. I need to look for or add o-rings to complete the passage efficiently. Is there any difference between bb and sb dist's that could cause this problem?

Originally Posted by bigred1957

I see, so by what your saying, my distributor could be the next place to look? It is aftermarket but I haven't looked into it yet. I need to look for or add o-rings to complete the passage efficiently. Is there any difference between bb and sb dist's that could cause this problem?

well what i am saying is with MSD they have o rings nice to have .i roll the cast on the bore hole on the block so they do not cut O rings going in . i have never seen this so bad that you would get low oil psi or nothing but it would not hurt to check ...there allways a first time.... so check the dist for size next to another one stock GM one or one out of a running engine.if not i can get you a size if you need it . if it a cheaper china one could be off .i used the MSD and MALLORYS AND ACCELS AND others never had a lost of oil psi from this.but you need to start some place .look what Jerry has posted and what i did as well as others .make a list and check every thing we posted on this.here s is a photo of how close the rockers can get to the upper boss of the valve coves can rub if you look on number 8 and 1 intake rocker by the upper valve cover bolt

I understand about the o-rings, I do have an old stock distributor to compare with. I'll definitely dig through the posts for info, everythings been helpful so far. Thanks alot for your help Pat, If I run across something wierd I'll fill you in.

Sorry to bug you again Pat, or anyone who has ideas but I'm still having a knocking I can't figure out with my 402. I've checked out most everything we've discussed plus I've replaced a couple of valve springs that were under spec (but not by much). The timing chain has about 4 degrees of slop but I was thinking of checking it anyway. Also I was going to check if the cam has a retainer plate that could be getting loose. My thoughts are at the point of pulling the motor and tearing it down but until I find work I just can't afford to do it. My brothers a mechanic and mentioned the possibility of a stuck wrist pin, but wouldn't the knock be all the time? Help, I'm losing it.

BTW it's interesting you mentioned 1 & 8 intake as the rockers that are close as those were the rockers that were hitting on mine! Thanks again!

Originally Posted by bigred1957

BTW it's interesting you mentioned 1 & 8 intake as the rockers that are close as those were the rockers that were hitting on mine! Thanks again!

i built and machine alot of bbc over the years thats how i make a buck what pistons do you have and what heads on that 402? if you use a close rect port pistons on a O port head they hit a on the ex side of the dome seen many that hit