Connecting rod squirt holes?

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dibbons

dibbons

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Got the heads off the .040 over 340 I purchased. Before removing the rotating assembly, I wanted to make sure the connecting rods and caps were marked. Can't find any numbers imprinted on them, so I purchased a little number set at Ace Hardware. My question is this: it looks like the flat area where I plan on staking the numbers has some kind of squirt hole right there. Are these squirt holes installed correctly? I don't remember seeing them there in my past small block rebuilds. Thank you.

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And is this rod cap supposed to have that little ledge showing on the left, where it appears the cap could be over to the left a little more to make it fit better? It does not seem to be a perfect match, maybe it's not supposed to be.

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The squirt holes point to the center of the engine and the anchor slots go outboard. They spray the opposite cylinder with oil....
 
IT's just casting flash and has not one thing to do with spacing or fitment, AND if you get anal about it and grind them off you will very likely be changing the rotating assy balance.
Not by much probably, but still. (say a couple of ounces if four or five rods have those.

My own opinion on marking the rods and caps in that location would not be a very good idea.
When you punch a mark in that surface it will distort the machined flat mating surface a little.
Maybe if the cap and rod were bolted up to torque when you punch it, it might be ok but do it very light.

Obviously just one persons opinion.
 
if you want to mark them , use a dremel with a metal engraving bit in it instead of pounding on them
 
They're not stamped on the other side? Pretty much any engine I've seen had some kind of mark to match rod to cap. The 360 I have apart right now has symbols, ie: tree, triangle, square, etc...and they're stamped on the side opposite the squirt hole.
 
Check the opposite side of the rod and cap for a number stamp. The factory usually stamped matching numbers on the rod and cap
 
This is one of the first things I was taught when I worked in a machine shop when I was a kid. The squirt hole is called a pee hole. The following is the formula to remember. "Pee-hole to the cam, numbers/locks to the outside." Now back in the 60's when I was taught this, we didn't see many or any 4 banger stuff, so can't say for sure on those engines.

Russ.
 
I took a cap off already and there are no markings that I could see. If the pee hole goes toward the cam, then in this case the pee was spraying all over the windage tray and not the opposite cylinder wall. (I suspected I would find some other screw ups when I found the notches on the rocker shafts were both toward the rear of the engine). With all that oil not having sprayed in the correct location, I wonder how the skirts of those pistons will look.
 
krazykuda said:
The squirt holes point to the center of the engine and the anchor slots go outboard. They spray the opposite cylinder with oil....
Click to expand...

I'm sorry, I don't know what is referred to as "anchor slot", is that part of the connecting rod? Outboard of what?
 
dibbons said:
I'm sorry, I don't know what is referred to as "anchor slot", is that part of the connecting rod? Outboard of what?
when you pull a cap, the bearing tangs have to be to the outside!!!! the squirt hole goes to the inside!!!! in other words they are in backwards. any service manual will show correct placement. only engine with tangs to inside are a ford!!!!
Click to expand...
 
Anchor slots are the flat tabs in the cap and rod that are used to oppose each other and keep the bearing from spinning. Here they are shown below:

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Here shows the cap and rod with the anchor slots circled in red, and the squirt hole in yellow. The anchor slots always go back to back. The anchor slot on the rod goes on the same side as the anchor slot on the cap as shown in the first picture above. Same with the main bearings.

The squirt hole points to the center of the engine or opposite cylinder and the anchor slots go to the outboard side of the engine when installed.

DSC04918 B2.jpg
 
You may also want to check the pistons. If they need to be installed a certain way, there should be a mark or notch toward the front of the piston that goes to the front of the engine. The rods and pistons must be pinned to make sure that the piston mark and squirt holes and anchor slots are in the proper relationship to each other....
 
dibbons said:
Yes, the pistons all have their notches pointing forward on both banks.
Click to expand...

Then if you change banks, the squirt holes will line up with the pistons pointing forward...

Just swap them across 1 - 2, 3 - 4, 5 - 6, 7 - 8...... Then the pistons will point forward and the squirt holes/anchor slots will be correct also....

I would get a Mancini Racing "refresh kit A or B" for $230 and replace the main & rod bearings, rings, and gaskets...

A "B" kit:

Sealed Power Engine Kit - "B"


Refresh kit main page:

Engine Rebuild Kits
 
Thanks, I didn't thing about just swapping banks. But I may have another glitch/problem. I have never checked rod side clearance before, so I hope I am doing it right with feeler gauges. Factory specs I found in two different sources show either .006-.014" or .009-.017" (take your pick). I am measuring this: Rod #1 @ .020, #2 @ .025, #3 @ .016, #4 @ .014, #5 @ .020, #6 @ .018, #7 @ .020, #8 @ .020. I am no machinist, but I can't think of anyway to tighten things up. Neither can I think of what would happen if I reassemble the rods with the out of spec clearances. When measuring, I stick the feeler gauge between the side of the rod that is closest to the crankshaft like in some fotos I have seen.
 
Side clearance CAN be important for oil control flowing through the rods.

But, as a point of reference, the SCAT rods that you can buy for these SBM's have narrower rod big ends, and the side clearance with those rods compute out to about .025-.027" with standard journal widths. We put a set in and the side clearances were just that, around .026", and I did measure the journal widths to be right on spec. No problems so far (we DO run an HV pump with it 18-20% extra flow), and I have never read any complaints about this wider side clearance being any issue with the SCAT rods.
 
Good info. I have been reading comments lately about how the high volume oil pumps are not really that necessary, but in this case one of those might save the day!
 
I don't think the side clearance is extremely critical. Of course, you don't want to be able to drive a bus through there, but I don't think .020" will hurt anything.
 
My first 340 i built had a lot of side to side oil clearance between the two rods. machine shop said it would be ok with the HV oil pump i was using. With 20w50 oil at idle and hot i had 10 psi. would go way up with rpm but at 700 rpm it barely moved the needle. Never had any problem with it.......just didn't like it. A couple years down the road i found some NOS stock rods.( payed 5 buck a rod for them!!!) pulled the eng down for other oil leaking problem and decided to re ring it with the new rods.
same everything including the pump.(new bearing of course) oil pressure when to 60 psi HOT! that's when i started experimenting with thinner oils End up with a 5w20 w 25 psi at idle hot. My et showed it made more power too!
I don't remember how big a gap was between the rods but i do remember that with the new rods it was is spec.
 
dibbons said:
Thanks, I didn't thing about just swapping banks. But I may have another glitch/problem. I have never checked rod side clearance before, so I hope I am doing it right with feeler gauges. Factory specs I found in two different sources show either .006-.014" or .009-.017" (take your pick). I am measuring this: Rod #1 @ .020, #2 @ .025, #3 @ .016, #4 @ .014, #5 @ .020, #6 @ .018, #7 @ .020, #8 @ .020. I am no machinist, but I can't think of anyway to tighten things up. Neither can I think of what would happen if I reassemble the rods with the out of spec clearances. When measuring, I stick the feeler gauge between the side of the rod that is closest to the crankshaft like in some fotos I have seen.
Click to expand...
Clearance is per pair.
Rods may have a large chamfer on one side and a small chamfer on the other. The large chamfer goes to the crank cheeks where a large radius may appear. Since your rods are all messed up, the chamfers will be too.Check for damage.
 
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Well, that's right, there is only one gap per pair. I was pushing each pair to the right, measuriing the gap on the left, and then vice a versa. In other words, the gap for each pair varied between .014" and .025", depending on which side of the crank journal i was using. Actually, I don't see why the measurement can't just be taken between the rods themselves, which is what I was also trying and the result was pretty much the same.
 
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