265 oiling question / high RPM lifter noise

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I'm turning them to a full turn tonight. I checked the studs with a straight edge right away and I doubt its valve float, I've only heard valve flost a few times and I don't hear it for sure. I HOPE I'm not floating them at 3000!!!! The springs are new and the right tension but once again, I'm not making this thing scream or anyhting, this is just highway speed. Ya know?

 

You really got to wring a motor's neck to get valve float

 

Yeah, I know. But it would be my luck. I'd be the first guy to float valves below 4000.

 

A trendsetter, or pioneer

 

BTW, I really dig you car man. I've got a '64 as well. Sweet ride!

 

Theory,,,

With the addition of the hyd lifters, too much oil staying in the top of the engine when the engine gets up to highway speed. (insuficient drainback holes etc.?)

So much oil is staying up, that the oil pump is ****ing air, not so much to drop pressure, but enough to make your lifters colapse.

Add a quart of oil and see if this helps....

 

That's a good theory! I'll try that

 

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This was a suggestion from TriFive.com...

"I recently completely rebuilt the 265 in my 55. The cam I used was a custom comp cams grind, and in my numerous conversations with comp we decided the best way to solve the oiling issue was to cut the groove ALL THE WAY around the rear cam journal. No pulsing. I left the block stock and made sure the cam bearing was lined up correctly. Theoretically the rockers would oil with the cam standing still. I was getting oil at the rockers with the pre-oiler. It has not made so much as a tick. I did 3/4 turn preload."

 

It seems the trick is to modify the block for constant lifter valley pressure or try this new idea. The stock 265 distributor SHOULD flood under full pressure so you (and I) need to use a '57 and up splash oil type distributor. I'm going to try the full notch idea since the roundup is so close, and with my latest luck I dont want to tear my motor completely apart again.

 

try the 3/4 turn---it won't hurt. if that don't fix it, look elsewhere. hope it works out---40fordtudor, rowlett

 

I tried 3/4 and nothing changed at all. This thing is for sure starving the top end of oil. It has to be. I think the full groove will happen tonight.

 

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Man this is making me nervous to get my 265 back from being built. I didn't have the machine shop do the full pressure oiling stuff like B*** did on his but I also was not expecting huge numbers. I am also going to use a old Mallory dizzy which I hope works.

I wonder how cutting a full groove around the whole cam would work out? Doesn't seem like that was ever necessary before so I am sure there is a fix for it elsewhere.

 

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My dad said he remebers seing a rear journal with a groove all the way around it before. I wonder if there was a short period where it was offered by a couple cam grinders.

 

I think the notch would keep coming back around way before the lifters had a chance to bleed down. So, if I'm reading this correctly, I don't believe it will be your fix

 

Early big blocks

 

I know, that makes sense too. I'm just at a loss. I'm leaning on the fact that GM found the pulsing oiling system to be inferior and made it constant pressure after '57. All I can do is hope!!!

 

I was also given the idea of shimming the oil pump spring to boost the pressure keeping the lifters pumped. Still debating.

 

lifters can stay pumped with as little as 8lbs

 

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That name makes me laugh.

Before you doing anything else to the engine, let me ask some questions.

1. Did you have the engine at full operating temperature when you adjusted the valves?

2. Was the engine running and was it set a the correct idle speed when you adjusted the valves?

3. Did you adjust each valve in quarter-turn increments being sure to wait 10 or 15 seconds between each quarter-turn until the engine smooths out again before making the next turn?

If not, then that is what you should do before going on to more drastic measures.

Oh, the 265 used 3/4 turns per valve for zero lash so you should make three quarter-turns on each with the 10 second pauses.

Hope this helps

SAFU

 

Yes the engine was at full temp but I didn't adjust them running. I've never had a bit of trouble with ANY engine adjusting them with the engine off. I 'll give that a shot before I yank the cam tonight. I'll try just about anything at this point.

 

Just so you will know. Adjusting the valves with the engine running was/is SOP on these motors especially if the static adjustment does not get the job done so this is hardly anything radical. Both my old Motor Manual and Chiltons give this procedure, although the Motor Manual gives greater detail. Remember 3/4 turns is the maximum on a 265, and gives zero lash.

Put a new gasket on the head with some silicone under it, let it set up and it will help keep the oil from getting everywhere. It can be messy, but well worth the effort to get things right.

Hell they used to make a special tool to do this while the engine was running, but a wrench and a screwdriver work just fine. You can also buy little clip on oil deflectors that go on the rockers to help keep the oil from going all over, but I've never had much luck with them. One way of handling the mess is to take an old pair of valve covers, and cut the tops off. Glue 'em down and they will keep in most of the oil and still give you access to the adjustments.

Just for the record, doing this while the engine is running will also give you an idea of how well the top end is oiling.

Hope this helps.

SAFU

 

Running or not, at temp or not....if they're wrong, they'd be noisy all the time.

 

Maybe something here will help. http://forums.corvetteforum.com/c1-and-c2-corvettes/2295021-265-rebuild.html

Some of these guys really know the old chevies (JohnZ etc.)

 

OK, I just talked to my Machinist of over 30 yrs. He says, it's "possible" at RPM the cam may be walking forward or back just enough to keep that notch from doing it's job, and that's to connect the two holes in that last bearing. SO, again, do NOT full groove it like I said earlier, but maybe broaden the notch in all directions by a small amount

 

I hope I'm not ******* you off yet, it seems I have an excuse for all of your suggestions! I actually made the groove just a bit bigger before I installed it to ensure I wouldn't have any trouble with on e of the holes being covered up.

 

So whats the next step guys? I REALLY appreciate everyone's insight on my problem. I really do! I'm so confused now.