340 Oil Priming Question First Start

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If you are running hydraulic lifters you need to put some angled grooves on the shaft across the oil feed holes.

If you don’t, the rocker will grab the shaft.

Should be done with solid lifters too.
 
Newbomb Turk said:
If you are running hydraulic lifters you need to put some angled grooves on the shaft across the oil feed holes.

If you don’t, the rocker will grab the shaft.

Should be done with solid lifters too.
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Does the lack of a groove explain my oiling deficiency? The whole reason I am at this point is because I am seeing little to no oil coming out of the rocker arms. Not a drip on many arms.

We jointly found that the passenger shaft IS REVERSED and will need to be corrected.

However now I am dealing with the inadequacies of a modified set up. And I will need more guidance on this mod.
 
340inabbody said:
Does the lack of a groove explain my oiling deficiency? The whole reason I am at this point is because I am seeing little to no oil coming out of the rocker arms. Not a drip on many arms.

We jointly found that the passenger shaft IS REVERSED and will need to be corrected.

However now I am dealing with the inadequacies of a modified set up. And I will need more guidance on this mod.
Click to expand...

No, but without the grooves you can’t get enough oil between the rocker and the shaft and the rocker will grab the shaft.
 
Those shafts look like they are from a stamped steel set up. You can tell by the large oiling holes. Adjustable 273 rockers have 2 oiling holes per rocker on the shaft. One near the loaded side of the rocker base (Should have a banana groove, but they all don't) and one to feed the rocker adjuster with a dribble amount of oil as the rocker moves up and down (timed exposure).
 
CFD244 said:
Those shafts look like they are from a stamped steel set up. You can tell by the large oiling holes. Adjustable 273 rockers have 2 oiling holes per rocker on the shaft. One near the loaded side of the rocker base (Should have a banana groove, but they all don't) and one to feed the rocker adjuster with a dribble amount of oil as the rocker moves up and down (timed exposure).
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Maybe I read this incorrectly. Are you saying that the shaft is not the correct one for the 273 rockers?
The rockers do have two holes indeed. Not sure about any banana grooves?
 
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273 banana groove shafts.
61F13758-072D-4E01-A453-D514D35CA25D.jpeg

It’s pretty easy to duplicate the groove with a dremel and a thin cutting disk. Might be easier if you don’t have the tools to buy a set of shafts. They come up for sale quite often.
 
These are the banana grooves. Kinda funny that I searched banana groove shaft and the picture to the left is my toasted rocker.. :):)

EA34CFBF-815C-46E5-9EA1-B47BBD7629EB.jpeg
 
CFD244 said:
The shafts have 2 holes per rocker as well.

Did you say that you are running hydraulic lifters?
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2 holes per rocker? Mine appears to have one. Is there another on the ither side of the banana as pictured?
 
Alright, here's what the oiling holes look like on the shaft.....

When viewing the assembly from the front of the engine, the hole with the banana groove is pointing slightly towards the outboard side of the engine since it is not centered. The banana groove is especially important here with hydraulic lifters because of the lack of lash that allows oil to circulate around the shaft when the valves are closed (solid lifter). With hydraulic, that moment of rest does not occur because of your preload and the oil has a harder time getting between the shaft and rocker.

That groove has to be located there because it is the point of the rocker that gets loaded the most when the valves are being opened. The other hole is located inboard and feeds the arm area of the rocker. It is a timed event and a little oil finds it's way into the rocker as the rocker hole passes the shaft hole. This keeps the adjuster lubed.

Like I said before, it looks like you have the wrong shafts for your application (one big oiling hole)

Take a real close look at the insides of all of your rockers.....If you see evidence of galling or grooving, best to replace everything. If the rockers are awesome, you can get by with a good set of shafts.

PM @Rocket He has had some shafts for sale in the past.

Good luck

Any questions, just ask.

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More knowledgable people here than me, but I bet those are hydraulic shafts, thus the discrepancy. You should buy a set as mentioned with banana grooves. If used ones, make sure they are in great shape. Also while we are here post pics of your lifters to confirm if they are solid vs hyd.
Were getting somewhere :thumbsup:
 
CFD244 said:
Alright, here's what the oiling holes look like on the shaft.....

When viewing the assembly from the front of the engine, the hole with the banana groove is pointing slightly towards the outboard side of the engine since it is not centered. The banana groove is especially important here with hydraulic lifters because of the lack of lash that allows oil to circulate around the shaft when the valves are closed (solid lifter). With hydraulic, that moment of rest does not occur because of your preload and the oil has a harder time getting between the shaft and rocker.

That groove has to be located there because it is the point of the rocker that gets loaded the most when the valves are being opened. The other hole is located inboard and feeds the arm area of the rocker. It is a timed event and a little oil finds it's way into the rocker as the rocker hole passes the shaft hole. This keeps the adjuster lubed.

Like I said before, it looks like you have the wrong shafts for your application (one big oiling hole)

Take a real close look at the insides of all of your rockers.....If you see evidence of galling or grooving, best to replace everything. If the rockers are awesome, you can get by with a good set of shafts.

PM @Rocket He has had some shafts for sale in the past.

Good luck

Any questions, just ask.

View attachment 1716250598

View attachment 1716250599
Click to expand...
Thanks for the definitive response. Yup I have the wrong shafts. One rocker is gauled the others perfect.
4spdragtop said:
More knowledgable people here than me, but I bet those are hydraulic shafts, thus the discrepancy. You should buy a set as mentioned with banana grooves. If used ones, make sure they are in great shape. Also while we are here post pics of your lifters to confirm if they are solid vs hyd.
Were getting somewhere :thumbsup:
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The picture I posted is the best I have as the intake is back on. I ASSUMED they were hydraulic but I am NOT familiar enough to have determined this by sight.

Is there another way to tell now that the manifold is back on? Like the springs or compression of the lifters etc? The springs look super stiff like what might be used in a solid lifter set up.?.

image.jpg
 
CFD244 said:
Alright, here's what the oiling holes look like on the shaft.....

When viewing the assembly from the front of the engine, the hole with the banana groove is pointing slightly towards the outboard side of the engine since it is not centered. The banana groove is especially important here with hydraulic lifters because of the lack of lash that allows oil to circulate around the shaft when the valves are closed (solid lifter). With hydraulic, that moment of rest does not occur because of your preload and the oil has a harder time getting between the shaft and rocker.

That groove has to be located there because it is the point of the rocker that gets loaded the most when the valves are being opened. The other hole is located inboard and feeds the arm area of the rocker. It is a timed event and a little oil finds it's way into the rocker as the rocker hole passes the shaft hole. This keeps the adjuster lubed.

Like I said before, it looks like you have the wrong shafts for your application (one big oiling hole)

Take a real close look at the insides of all of your rockers.....If you see evidence of galling or grooving, best to replace everything. If the rockers are awesome, you can get by with a good set of shafts.

PM @Rocket He has had some shafts for sale in the past.

Good luck

Any questions, just ask.

View attachment 1716250598

View attachment 1716250599
Click to expand...
Wow great definative post! Figures one rocker is gauled the rest look clean. So what’s the story on the banana shafts? Were they made like this? Are they no longer available new?
 
Hydraulic lifters will have a retaining clip in the top of em. Pretty easy to identify. Solids will not. You can peek down with a flashlight and see it through a pushrod hole even with the intake on. Another way to tell is take a pushrod and seat it in the lifter and push down on it. You’ll get some spongy movement. If the engine has just run or been primed this is a harder way to identify them as the lifters will be pumped up. Below is a hydraulic lifter.
C3747DB9-94DF-4F40-8E2F-597596D1B065.jpeg
 
Not to confuse the discussion but these original 1965 273 rocker shafts only have one oiling hole per rocker (the rocker has 2) and it is oriented towards the pushrod side. The notches on these shafts are half moon shaped.

IMG_20240516_130827.jpg
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TT5.9mag said:
Hydraulic lifters will have a retaining clip in the top of em. Pretty easy to identify. Solids will not. You can peek down with a flashlight and see it through a pushrod hole even with the intake on. Another way to tell is take a pushrod and seat it in the lifter and push down on it. You’ll get some spongy movement. If the engine has just run or been primed this is a harder way to identify them as the lifters will be pumped up. Below is a hydraulic lifter.
View attachment 1716250606
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Don’t see any retainer or clip unless it’s perfectly circular and then I am not sure if that could even be a clip in there. For sure no square clip like the one you have shown. No compression noted when pushing on the lifters.

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IMG_2046.jpeg


IMG_2043.jpeg
 
Ok so my rocker shafts are wrong and beat up. My rockers are galled (some). At a minimum I need to replace a lot of the components. Looks like I am running a solid lifter set up. I don’t know the spring pressure nor can I measure it. I don’t know the required rocker ratio and never worked on a valve train before (other than setting valve lash).

Can I buy a set of something like these and put them on set valve lash and be good to go?

image.jpg
 
Save your money and use what you have. You buy something like those rockers and you are going way backwards. None of those aftermarket rockers are worth a crap unless you correct the geometry.

Polish your shafts and grind a groove for oil.

Get a brake cylinder hone and hone the rockers just enough to knock off the high spots and then send it.

I’ve run low 10’s with those rockers and every one of them had scores in the bores from guys not running enough oil pressure at idle and not having grooves in the shaft.

What you have is fine, just clean it up a bit.
 
Newbomb Turk said:
Save your money and use what you have. You buy something like those rockers and you are going way backwards. None of those aftermarket rockers are worth a crap unless you correct the geometry.

Polish your shafts and grind a groove for oil.

Get a brake cylinder hone and hone the rockers just enough to knock off the high spots and then send it.

I’ve run low 10’s with those rockers and every one of them had scores in the bores from guys not running enough oil pressure at idle and not having grooves in the shaft.

What you have is fine, just clean it up a bit.
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Thanks! That would be great to reuse them. What about only having 1 hole as opposed to two? I am not getting oil to flow to the top end.
 
From the factory some had banana grooves and some didn't. Post a want ad if you want for shafts/rockers, should set you back around $200 for used.
 
340inabbody said:
Don’t see any retainer or clip unless it’s perfectly circular and then I am not sure if that could even be a clip in there. For sure no square clip like the one you have shown. No compression noted when pushing on the lifters.

View attachment 1716250618

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There are a few different styles of retaining clips in hydraulic lifters my pic was just an example. What you have sure looks like a hydraulic to me but the pics are not clear enough to tell for sure. Don’t assume, be 100% sure of what you have because how you adjust them will matter. And I could not agree more with @Newbomb Turk use what you have just make it right. Even if you have to buy shafts.
 
So guys what is the difference between the shaft with 2 holes per rocker and one? Could this be my oiling issue?
 
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