Dauntless V6 Push Rods

I've searched a bunch on this topic and most of the threads end up off topic talking about the differences between 225 and 231 rocker arm oiling.

I'm replacing the push rods on my 225 build. I ordered Comp Cams 7869-12 from Summit Racing. The length is the same. Does it make any difference that they are hollow instead of solid?

I'll start another thread with all my other engine questions once I actually start building it

 

I do not know for certain but I would say it probably does. Normally the hollow ones have a hole in both ends and oil actually travels through them.

I will see if my FSM covers the dauntless

 

Sorry my manual only covers the L and F heads

 

It looks, to me, that the heads on the pushrods are different sizes. Not sure if this will cause odd wear issues. This isn't much help but, according to Pat Ganahl's book on Buick V6 engines, " .....'75 and later engines which oil through the pushrods......"

 

My fsm doesn't say anything about them being hollow or solid..... Just says to check for wear on ball ends and replace if worn. Good luck on the build

 

The heads on the Comp rods are slightly smaller, however it is the correct P/N for the 225. I'm more worried about excessive wear since the oil coming from the rocker will more or less drain right down the hollow push rod, however I probably just being paranoid.

 

Which one was solid? The original or the new ones? If the new ones are the hollow ones I would guess it is fine. Not sure but that is what I would think

 

As mentioned before the 231 are pressure oil fed through the pushrod while the early odd fire 225 motors are fed through the rocker shafts............both systems seem to work OK but the later is an improvement over the Odd Fire as the oil to the rockers comes from a small hole drilled in the block that goes through the head from the oil galley to the rocker shaft..............Your still going to get oil at the tip..........Make sure the ball radius fits the rocker and the lifter correctly.

 

The stock rods are solid with a slight dimple on each ball end. The new replacement rods from Comp Cams are hollow.

 

Do the lifters have a corresponding oiling hole in the cap? The stock 225 lifters have solid caps and if using that style, my guess is that there would be minimal oil going either way in a hollow rod and they should work just as well as the solid stock version if the ends fit the rockers.

 

I'd guess it's easiest to build them hollow. They could use the same jig and materials for many different lengths.

I agree with Duffer.

You could call the supplier and ask if it worries you.

I'd be inclined to reuse the factory push rods, if there's nothing wrong with them. Not much to them...

 

I'm pretty sure that at least one of stock push rods is bent, however that was just at first glance.

 

Usual test is to roll them on a piece of plate glass. Any bend should be visible.

Solid Sealed Power push rods are available from RockAuto for $2.49 ea. http://www.rockauto.com/info/SealedPower/RP3173.html Maybe just replace the bent ones? And return the others?

 

Those Sealed Power rods would be too long at 8.723". The Comp Cam rods measure 8.684".

 

I would have to assume that if you use the hollow ones the rocker tip would have a greater chance of starving for oil. This caused by the ease of oil being forced into the tube instead of staying on the head(in the divot)causing premature wear. The tube will fill eventually but I don't think it will be quick enough.

 

SO the comp cam rods are required with your cam? I thought you bought them in addition to your cam kit. The only way the shorter rods would be needed is if the lifters you got with your cam are taller than factory, or if the cam has a larger heel diameter than the factory cam.

If they are different lengths, I would measure the preload and choose a length according to that. http://www.compcams.com/v002/Pages/...HydraulicLifterPreLoadNonAdjustableValveTrain

 

The stock rods are 8.686 or thereabouts. All I'm looking for is a replacement for the stock rods in case my originals are bent.

I will check the original rods tonight. A Comp RV cam came with my master engine kit, not sure on the brand of the lifters.

This thread is where The confusion all started:
http://www.earlycj5.net/forums/showthread.php?83753-Buick-225-pushrod-length

 

Just rolled all of the rods on a piece of glass from a picture frame, 5 out of the 12 have a noticeable wobble.

The length of the stock 1971 pushrods is right about 8.684. The Comp Cams rods measure the same.

The width of the tip at the widest part on the Comp rods is roughly .312" The width of the widest part of visible tip wear on the stock rods is roughly .345".

The lifters that came with my engine kit are from Engine Performance Warehouse, P/N HA896. The are identical to the stock lifters in height, but the socket where the push rod sits is marginally larger.

Starting to think that I should return these push rods and find another set.....

 

My understanding is that the rods are solid to help with lubricating the rocker seat. Hollow rods are to feed oil to the lifters. With the 225 motor, oil is already supplied to the lifters through passages in the block. I installed the solid ones.

 

Actually with the 231 the lifters feed oil to and through the pushrods to the rocker arms. With the 225 the rocker arm pivots and upper pushshrod pivots are fed from the ricker shafts and rocker arms.
The correct parts are readily available. Why try to mix and match? Just use the correct parts and move on.


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