[Gach]

Originally Posted by tom s

Mike,just have all cycs sonic check!Tom

Agree 100%

[242177P]

Originally Posted by TRADERMIKE 2012

is there a way to inspect this area from behind using one of those cameras on a flexible wand, like used by a swat team?

You mean the incredibly common inspection cameras that you can buy pretty much anywhere? Harbor Freight has five different models.

https://www.harborfreight.com/search?q=borescope

[steve25]

Mike that would be nice , but on a V8 motor you can’t push the pistons out into the crankcase enough to remove them even with the crank removed.

Even if you could do that and install new rings just how the heck could you compress the rings to the pistons back in with no flat surface to seat the compressor on?

Tool rental shops will rent you a ridge reamer for some 20 bucks should you ever have this need again.

[TRADERMIKE 2012]

https://youtu.be/unwAKlCdyas

https://youtu.be/whtJvMIELtM?si=n_JyRWgY73gZ2xeA

https://youtu.be/_NxFRoN-Qok?si=hW-fnSy6rk7Vw9_K

https://youtu.be/IUJDrHR1qsc?si=iClEI5kYylsw9b-L

https://youtu.be/KM1zv118ubs?si=G1frdtSjDYFR6lxM

https://youtu.be/hJBlMMES77I?si=RfMowAgLKfUtWW4j

https://youtu.be/hJBlMMES77I

https://youtu.be/YaVu8FiUhLQ?si=GcBJ3NIrqFjHkiMG

https://youtu.be/wdczn-haJZM?si=gP9GvIvDKUZ6kih2

https://youtu.be/R8MYa8zKuU0?si=xfb18l-UluhVOL-3

https://youtu.be/X3Crh_URvrk?si=7GdqWN8dpzY_KBDT

https://youtu.be/X3Crh_URvrk?si=37_uTWH-ZUWy_ks-


https://youtu.be/qQJ6LCOSvmI?si=cwVEArCzzPjjqroQ


Mikes reply:

The number 8 cyl has a suspect (deep dime size) area at the top wall that might come out when bored, however what caused the anomaly in the first place? Lou said it looks like someone hit the cyl. wall with a ball-peen hammer.

If this is the result of poor machining or a cast sand event is questionable, it sure did not seal good at that location, JMO.

P.S. Are these grounds to sleave this cyl.?

I am concerned with what this area looks like behind, as viewed from the water jacket area!

Behind this problemed area, is there a chunk of cast material missing or rusted, is there a way to inspect this area from behind using one of those cameras on a flexible wand, like used by a swat team?

[TRADERMIKE 2012]

Originally Posted by steve25

Mike that would be nice, but on a V8 motor you can’t push the pistons out into the crankcase enough to remove them, even with the crank removed.

Even if you could do that and install new rings, just how the heck could you compress the rings to the pistons, back in with no flat surface to seat the compressor on?

Tool rental shops will rent you a ridge reamer for some 20 bucks should you ever have this need again.

Mikes reply:

Thank you for the info., I simply did not know when to use my ridge Reemer.

[b-man]

When I was having my 421 block bored .031” oversize for some 4.125 pistons I had purchased (stock bore is 4.09375) it came to our attention that someone had ruined the upper 3/8” of the bore using a ridge reamer sometime in the past while doing a ring job on the stock pistons.

I sold the 4.125” pistons and bought a set of 4.135” pistons which was the smallest size the bores would clean up at. I guess buying the pistons beforehand was a mistake, I was trying to expedite the process by purchasing what I thought would be the right size. However they would have been right if someone hadn’t screwed up by getting heavy handed using a ridge reamer.

A ridge reamer was commonly used in the past when someone wanted to do an economy rebuild keeping the old pistons. If you’re doing a proper rebuild with new pistons just skip the ridge reamer nonsense and get those old junk pistons out of there, who really cares if you break some rings or damage pistons that are already destined for the scrap bin.

[TRADERMIKE 2012]

Originally Posted by Kenth

1. You are measuring at the wrong spot.

2. All rods have a chamfer to leave room for the bearing to the radius on crank.

Look closer. Also, the rods are offset and need to be positioned with the notches towards radius on crank.

You can NOT just look at the spurt holes.


If there are no notches on rods (aftermarket) you need to check how the bearing sits in the rod, the side with more room goes towards radius on crank.


Your 1967 and earlier rods are cast I-beams. 1968 and later rods are reinforced at the big end as shown on my picture.

Mikes reply:

Thank you for the visual, it helps, it is hard to see the Beveled edge/champhor on the large side of the Rod, perhaps I should pull the Bearings out and inspect the area.

One easy way to determine the side of the Rod that goes toward the radius of the Crank or that faces each other is to associate the Rods marker @ the top of the Rod Pin area that has the two-digit number over it and orientate that visual, that I understand and point that out to me, the marker faces inside adjacent to the Rod that shares a Rod Pin or outside toward the Crank Radius?

You said:

"How the bearing sits in the rod, the side with more room goes towards radius on crank.

Mikes reply:

It seems to me that one side looks wider than the other with the Bearings installed in the large side of the Crank pin.

I will go back and study that again, but still answer the above request, that marker is in the location for a reason, so let's use it, please, to confirm the orientation of the surfaces in question.

[TRADERMIKE 2012]

Originally Posted by b-man

When I was having my 421-block bored .031” oversize for some 4.125 pistons, I had purchased (stock bore is 4.09375). Then it came to our attention that someone had ruined the upper 3/8” of the bore by using a ridge reamer incorrectly. Sometime in the past, while doing a ring job using the stock pistons, they gouged the cyl. wall.

I sold the 4.125” pistons and bought a set of 4.135” pistons, which was the smallest size the bore would clean up at. I guess buying the pistons beforehand was a mistake. I was trying to expedite the process by purchasing what I thought would be the right size. However, they would have been right if someone hadn’t screwed up by getting heavy handed while misusing a ridge reamer.

A ridge reamer was commonly used in the past when someone wanted to do an economy rebuild by reusing the old pistons. If you’re going to do a proper rebuild with new pistons, just forget the ridge reamer process and get those old junk pistons out of there. Who really cares if you break some rings or damage pistons that are already destined for the scrap bin?

Mikes reply:

The Pistons and Crank are allready disassembled. I broke five Rings in the process, no big deal though, I learned my lesson about when to use the Ridge reamer. It sounds like a blessing in disguise, now that I read about all the various negative comments about the use of a misused ridge reamer cutting too much into the top of the cyl wall. One less thing for me to screw up.

[dataway]

Rod chamfer ..

[TRADERMIKE 2012]

Originally Posted by Kenth

1. You are measuring at the wrong spot.

2. All rods have a chamfer to leave room for the bearing to the radius on crank. Look closer. Also, the rods are offset and need to be positioned with the notches towards radius on crank. You can NOT just look at the spurt holes.
If there are no notches on rods (aftermarket) you need to check how the bearing sits in the rod, side with more room goes towards radius on crank.
Your 1967 and earlier rods are cast I-beams. 1968 and later rods are reinforced at the big end as shown on my picture.

Mikes reply:

I just got through studying your photos and if they are correctly drawn to Pontiac specs this is how I read the information, in simple terms:

Hopefully I get this rite, The ID Boss on the large end of the Rod to Crank Pin is orientated toward the Radius side of the Crank Pin.

The Piston Notch always points forward.

The Spurt holes always point toward the Cam, up and are supposed to get oil to the opposite Pistons Skirt, wrist pin and under the Piston Rod area.

The non-boss side of the large end of the Rod to Crank Pin is orientated toward the center and is adjacent to one another.

[TRADERMIKE 2012]

Originally Posted by dataway

Rod chamfer ..

Mikes reply:

Are you referencing the Caps angle, tapered in toward the center of the shared Journal and that angle keeps the Rods Cap from interfering with the outer weights of the Crank?

[tom s]

Mike,the rod Js have a fillet ground into the crank,the bearings need clearance to clear that radius!The insides dont need that clearance.Very EZ to see in the pic.Tom

[dataway]

Maybe this will work ...

[TRADERMIKE 2012]

Originally Posted by dataway

Maybe this will work ...

Mikes Reply:

My description using drafting nomenclature:

Where the center of two adjacent large Rod ends shares a Journal and at that Crank Pin Journal and Bearing area, there is a 30 degree down angle Bevel on the inner lower edge of the Rod to Bearing where the Rod Cap is missing.

To the right side of the above area, there is:

A vertical flat surface to 45-degree Bevel angled toward the lower Bearing on the lower Rod where it meets the missing Cap.

Since the right-hand side is adjacent to the counterweight, to the right points forward.

The two center Rod large ends with their Bearings and Caps share the inside and are adjacent to each other. This means they share the same Journal. The left side is toward the rear or counterweight area.

[dataway]

Look close, don't confuse the shadow at the tip of the left arrow with a chamfer ... it's just a shadow. The right arrow points out the actual rod big end chamfer.

It's very obvious when you look at a rod big end.

I added a red line to show the actual cross-section of the rod.

[TRADERMIKE 2012]

Originally Posted by dataway

Look closely, don't confuse the shadow at the tip of the left arrow with a chamfer ... it's just a shadow. The right arrow points out the actual rod big end chamfer.

It's very obvious when you look at a rod big end.

I added a red line to show the actual cross-section of the rod.

Mikes reply:

I saw that in the last photo. And tried to explain it in words.

Are you using Auto Cad or some other program, that has layers that you can turn on and off, I had two years of Drafting back in 1996?

[TRADERMIKE 2012]

Originally Posted by dataway

Look closely, don't confuse the shadow at the tip of the left arrow with a chamfer ... it's just a shadow. The right arrow points out the actual rod big end chamfer.

It's very obvious when you look at a rod big end.

I added a red line to show the actual cross-section of the rod.

When installing the pistons from scratch onto the bare Rods, install the Piston groove (arrow forward direction) to rods. Install 1,3,5,7, Piston on to the Non-ID Boss identification side of the large Rod end.

Install 2,4,6,8, on to the ID Indication Boss side of the large Rod end.

Those numbers on the charts are the ones we recorded when the engine was in the vehicle, we will provide new measurements. What we learn these days of where and how to record the correct data.

As pertaining to the drawing, on the bottom left, of the two Pistons. The draftsman should have drawn arrows pointing toward the notches at the top of each piston and denoted that they should face forward, when installing them in an Engine. Details like that keep engine builders abreast of part orientation, you can't have too much information. If we did not expect to see notches on the Pistons one would probably miss the slight difference, especially when reprinting in books is involved.

[TRADERMIKE 2012]

Originally Posted by tom s

Mike, just have all cyl's sonic check! Tom

Mikes reply:

With all the sonar equipment in Subs and used in medical equipment like ultrasound, it's no wonder this tech. has gone to the automotive use.

I have even seen my own heart while using some sound machine. They can even clean using sound. Even the army can kill using sound waves. What about what Tesler's experiments in NYC, he could have taken down neighboring buildings. Frequencies that can break glass or make music.

[tom s]

Mike,doing sonic on blocks has been around a LONG time!Just get it done.Tom

[dataway]

I just edited my original photo in a paint program and re-saved it.

Although I do have AutoCad, Inventor, Solidworks, 3ds-Max, Fusion 360 etc. that I use to design various projects both real and imaginary (like my six valve, single cylinder, wobble plate valve train engine )

HiJack ended.

Originally Posted by TRADERMIKE 2012

Mikes reply:

I saw that in the last photo. And tried to explain it in words.

Are you using Auto Cad or some other program, that has layers that you can turn on and off, I had two years of Drafting back in 1996?