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Discussion Starter · #1 ·
I have a 265 Chev v8 with castiron auto .This motor was rebuilt about 7 years ago , but only done 3000 kms in that time short trips .
It is running a eddlebrock triple carb manifold.
I can run around town all day , in stop start traffic no probs , but get out on the open roads , the rockers start to get noisy and really hammer.
Take the rocker covers off , and let run for a while oil is all over the rockers. Then builded up the revs a bit, and the front 2 rockers on L and r side are dry . Yes i have replaced Hydrolic lifters, oil pump and blown air down all oil gallerys ,which arn't blocked .
Now the motor is pulled down , the bearings and every thing still measure the same as when put in. I have read every book on the 265 motor that i can get my hands on , but cannot still find the problem please someone help , any ideas will help Thanks from a 56 lover.
 

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'55 and'56 265's had two holes in the rear cam journal in the block. This feeds oil to the lifter galleries. A cam bearing with the matching two holes must be used. Also the camshaft has two flats ground into cam's rear journal.
 

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'55 and'56 265's had two holes in the rear cam journal in the block. This feeds oil to the lifter galleries. A cam bearing with the matching two holes must be used. Also the camshaft has two flats ground into cam's rear journal.
The back bearing on a 265 cam has to have a flat ground on one side so the oil can "pulse" up to the rocker arms when the flat lines up with the holes in the bearing. This is the only path. The lifters are unique to the 265 also.

It is my understanding that you can drill a bypass hole around the last cam journal to avoid using a cam with the flat spot on the rear bearing. This would make the engine like all other small blocks built since then. You would then also have to use the later style lifters.

True about the bearing requiring the holes unless you modify the block.
 

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Discussion Starter · #6 ·
I have a 265 Chev v8 with castiron auto .This motor was rebuilt about 7 years ago , but only done 3000 kms in that time short trips .
It is running a eddlebrock triple carb manifold.
I can run around town all day , in stop start traffic no probs , but get out on the open roads , the rockers start to get noisy and really hammer.
Take the rocker covers off , and let run for a while oil is all over the rockers. Then builded up the revs a bit, and the front 2 rockers on L and r side are dry . Yes i have replaced Hydrolic lifters, oil pump and blown air down all oil gallerys ,which arn't blocked .
Now the motor is pulled down , the bearings and every thing still measure the same as when put in. I have read every book on the 265 motor that i can get my hands on , but cannot still find the problem please someone help , any ideas will help Thanks from a 56 lover.
Well hello all from down under ,long time no talk to any body,well i'm back.
The motor lay around for 3 months, with lots of head scratching . In the end we just made the flat groove at the end of the cam deeper and wider , replaced rear main seal, new gaskets , then put back together.
Ran just as it should ,then alternator gave up ,fixed that , now speedo has seized so i have just pulled it out to send off to get rebuilt.
While all this was going on my computer just didn't want to work any more. So i went out and got a new one , well that is a story in itself . Brand new , key board did not work, got replaced , but still cannot download or post photos sorry. Or keep emails so sorry to the folks i have not replyed to.

Have a great day or night in your case and thanks fro Zac
 

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One problem solved always seems to lead to another......At least when you've got one of these old cars,you're never bored:D
 

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Discussion Starter · #10 ·
Well hello all from down under ,long time no talk to any body,well i'm back.
The motor lay around for 3 months, with lots of head scratching . In the end we just made the flat groove at the end of the cam deeper and wider , replaced rear main seal, new gaskets , then put back together.
Ran just as it should ,then alternator gave up ,fixed that , now speedo has seized so i have just pulled it out to send off to get rebuilt.
While all this was going on my computer just didn't want to work any more. So i went out and got a new one , well that is a story in itself . Brand new , key board did not work, got replaced , but still cannot download or post photos sorry. Or keep emails so sorry to the folks i have not replyed to.

Have a great day or night in your case and thanks fro Zac
Just under 12 months and a lot of money wasted on trying different ideas, even got a 283 motor rebuilt to run in my coupe .
But i did not give up and have finely fix the problem . I had a standard oil pump then a rebuilt 265 oil pump , but still noisy rockers .
Pressure was always around 40/45 PSI , put in a high pressure pump at last this worked , 55 to 65 PSI never was this good with all pumps and rebuilds that we had done before .
I just hope this helps someone else at half the cost .
 

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One wouldn't expect that to solve the problem, but I suppose stranger things have happened.

The extra pressure may be overcoming a restriction somewhere, or there's something strange with the lifters.
 

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Discussion Starter · #12 ·
One wouldn't expect that to solve the problem, but I suppose stranger things have happened.

The extra pressure may be overcoming a restriction somewhere, or there's something strange with the lifters.
Yes iam very surprised myself ,after 2 pull downs new old stock bearings and all other things read and sent to me tried . Before the pump was put in i tried all sorts of oil such as Penrite HPR 30, 40 and 50 and I am still running HPR/50 .
All thing were double checked when motor was pulled down for oil flow ,and new liffters and rockers used after the second pull down and still dry rockers after 80 mph on open road .
3 members in our club are running 265 V8s after rebuileds ,and have had NO problems .
 

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I'm still unsure if we were clear so just to further clarify, your cam's last bearing (towards the rear of the car) must have a flat spot machined onto it to allow the oil to pulse past. This is on the 265 V8 engine only.
How do I know?
It was the first mod I ever made to my '56 back in 1963. I put in a later (than '56) solid lifter Corvette cam and had to have that spot machined onto the bearing.

Forgive my cad skills please.......but that last bearing has to look something like the image below....if it doesn't, no oil to rocker arms.
 

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In addition to the above, the bottom of your distributor stem should have a flat ground in it to allow oil to pass.
 
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