Caveman's 'Anti-Rescue' rig '74 4x4

[SuperBuickGuy]

are you going to re-balance the bottom end?

[Beagle]

I don't think he took enough off to worry about it... before and after weight would be good to know but how close do they really get it balanced, and to what target RPM?

[yellomalibu]

are you going to re-balance the bottom end?

I bet he removed less than a gram of weight.. certainly no more than 2 grams. Having it re-balanced would be a nice boost to the machine shop's economy, but in all other ways, a waste.

[Beagle]

I bet he removed less than a gram of weight.. certainly no more than 2 grams. Having it re-balanced would be a nice boost to the machine shop's economy, but in all other ways, a waste.

Maybe one of the machinist guys on here will chime in and tell me since I'm an idiot and have a limited understanding of balancing voodoo - what the hell does +/- 2 grams mean on a balance? I can see where the pistons / rods are massaged to get them all about the same weight, then the bob weight computed, then the counter balances drilled or fattened up with mallory, but what do things like

50% factor (whatever percentage, what's that mean?)
Under Balance
Over Balance
and of course, +/- whatever gram ...

I spent a lot of time on one cylinders growing up. "Balanced" is a subjective term. lol. At what target RPM? I have - for reall - seen v8 engines come apart with 1 oversize piston in it that ran pretty smooth. Sure, it was a low budget deal but somebody was worse than me! I'd at least bore it's partner too. lmao.

[TheSilverBuick]

Looks good Tony!

[Caveman Tony]

Yeah, I discussed this with my machinist... good to go as is.

Especially since the target RPM is 1500, lol.

I honestly don't think the motor will ever see north of 3500-4000, and even if it did (if I missed a shift--HA!) the heads and cam are the rev-limiter on these. They lose steam at 4500 anyway. Good ole torquer peanut-ports.

[Caveman Tony]

Got the block, heads, & crank back from the machine shop: Only needed a hone, super-light polish on the crank, and a clean up in the hot-tank. He also did a light touch up on the valvejob, and assembled the heads with new stock valvesprings.



He even put all the freeze plugs & cam plugs in, along with a nice coat of engine enamel.

Dana recommended these cool aluminum bearings... said he's used them for a while now, and they look brand new after 20-40k mile teardowns.



Cleaned out the threads on the main caps...



Plopped in the crank...



Put on some Plasti-gage, settled-in the main caps with the brass hammer, torqued 'em down, and then pulled 'em off to measure...

Nuthin' outta whack here...



No pics of the cam install, I had a dead battery and was under the gun to get it in and still make it to the living room in time to watch the Patriots game. And then it was pack up my crap and drive back to NJ for work Monday mornin'.

[Beagle]

Was the polishing on the front throw a result of unintentional parts intermingling? Meh. SHINEY! Makes noise yet? Noise? huh? Huh? HuH?

I'm going out to ruin some perfectly good flat top TRW's in a 302 with a home made valve cutter. Wish me luck. lol. Good progress man!

[OldMachinist]

Definately no need to rebalance with what has been done to the piston and it looks like the grinding on the crank may have been done as part of a balance if that was done during the rebuild. When balancing I used to figure 4 to 5 grams for weight of oil in the bearings so its pretty inexact at those small amounts. What is crazy is how far off clutches are even though they are supposed to be balanced from the factory or rebuilder and this includes high performance clutches. I can't say for sure but it seems they are balanced to the nearest ounce instead of the nearest gram. ALWAYS balance the clutch disc and pressure plate when balancing an engine so equipped.

[Beagle]

Definately no need to rebalance with what has been done to the piston and it looks like the grinding on the crank may have been done as part of a balance if that was done during the rebuild. When balancing I used to figure 4 to 5 grams for weight of oil in the bearings so its pretty inexact at those small amounts. What is crazy is how far off clutches are even though they are supposed to be balanced from the factory or rebuilder and this includes high performance clutches. I can't say for sure but it seems they are balanced to the nearest ounce instead of the nearest gram. ALWAYS balance the clutch disc and pressure plate when balancing an engine so equipped.

you know, ounce, 28 grams, what's the difference. lol. That bothers me, I'm about to put a new clutch and PP and old flywheel in a car along with pistons and crank that came with an auto to begin with. You're screwin up my budget man! It won't see the high side of 5800 - but... crap. I guess I'll get it balanced...

[Caveman Tony]

I sanded down the sharp spots and the casting parting line when I rebuilt it the first time back in '07. Lol, its been balanced twice now since then, so it better be good.

I'm in dirty Jersey this weekend, I'll be putting on the timing chain and oil pump, etc next weekend. Then lifters, pushrods, rockers, intake, dizzy, the weekend after that...

[Caveman Tony]

So I mentioned earlier I had a huge crack in an exhaust manifold... I could probably go to any junkyard and find one, but I wanted to see how good my skills really are.

No, I'm not roasting a brisket on the grill... this is pre-heating the piece. Didn't work as well as I'd wanted, the charcoal didn't get much over 375 or so. Good for burgers, not quite enough for cherry red cast iron.



Tin foil wrap is to keep it from getting charred... worked on the grill, but it was ironic... note the pics after acetylene torch heating. Duh. Blackened catfish.



I made a jig out of some scrap 1/4" angle, to bolt the manifold to while welding. This was an attempt to keep the bolt hole from warping out of place.

You can sorta see the crack here, I didn't take any decent pics of it, but it goes practically all the way around the front-most bolt hole, a little ways rearward from it.



A little too much acetylene, not quiiiite enough oxygen...



The tin foil melted like eyebrows near a backfire... surprising...



The old man led some very helpful hands and expertise...



Here's about an hour into it... lots of re-heating, wire-brushing, short welding bursts, and re-positioning to let gravity help close the wound.









The chipping is pretty much mandatory after each pass, both to try to get out as much slag as possible, and also to 'peen' the weld and parent metal to release some of the internal stress from the weld cooling.



More reheating...



More reheating...



Ahhh, just the right shade of red.





Almost closed up... I ground out the crack, and it was in such a tight weird spot that my grinding opened up a channel pretty wide, like a full 1/2" in some spots.



Lots of building up one side, then the other, then let the puddle cool a little, then connect the dots.

Gravity is your friend, let the weld puddle fall into the hole a little, let it cool, it does the work for ya.



All closed up.



I'd heard from an old-timer at the Wendover cruise night at Bonneville that a cast iron weld will keep from cracking if you let it cool super slow... like 2-3 days.

His technique was to post-heat the part after welding, then bury it in a bucket of lime. Super fine particles, finer than sand... keeps the heat in for a long time.







Two 50-lb bags of lime, $7. I shoulda used three, but the store had already closed.





Still have a little brazing to do on the machined side of it, (easier to get it nice and flat with brass than super hard weld) but we'll get into that later...

[OldMachinist]

you know, ounce, 28 grams, what's the difference. lol. That bothers me, I'm about to put a new clutch and PP and old flywheel in a car along with pistons and crank that came with an auto to begin with. You're screwin up my budget man! It won't see the high side of 5800 - but... crap. I guess I'll get it balanced...

Didn't mean to cost you money and you might not even notice it. It depends on if you want it as good as you can get it, or just good enough to work as all engines will work with the factory balance on the PP.
When balancing, I used to spin and balance everything separately that went on the crank for best results. This included the front pulleys on the balancer and the PP. My thought was if anything had to be replaced it could be balanced before installation so the balance job was still good. We had an arbor to bolt flywheels to so replacement PP's could be bolted on and balanced and expandable mandrels for holding clutch discs or dampners if you wanted to balance pulleys bolted to the dampner. Of course if the engine is externally balanced you will need an internally balanced flywheel or dampner to separately balance PP's or pulleys.
Also something about balancing is imbalance comes and goes according to rpm. To illustrate, an out of balance tire will vibrate at a certain speed and then go away at a higher speed. It will vibrate again at double the speed of the first vibration felt so say it vibrates at 60 mph it will vibrate again at 120 mph and again at 240.
I don't know when the first vibration comes in an engine but I would guess its below 3000 rpm.

[OldMachinist]

I just realized what a jerk I am for hi-jacking your thread Caveman Tony so I want to apologize for that and I will shut up. I don't have much real world experience in most discussions here and when I get a chance to talk about something I know something about I tend to blabber too much.

[Scott Liggett]

I just realized what a jerk I am for hi-jacking your thread Caveman Tony so I want to apologize for that and I will shut up. I don't have much real world experience in most discussions here and when I get a chance to talk about something I know something about I tend to blabber too much.

I had my machinist weld a crack on my friend's 58 Caddy exhaust manifold cause they are impossible to find. He used some kind of powdered metal as the filler. It comes in a big plastic bottle like a big shampoo bottle. He said the stuff was insanely expensive, but it was well worth paying him $125 to do it for me.