Balancing a Flat head six

[jd52cranbrook]

How important is it? Being it is not a V type engine. This is next in line for my engine and was just curious.

[bob westphal]

Many old timers have told me that it's not necessary on these engines. However, every engine I have built in the last 10 years including flatheads has been balanced. Even the flywheel/clutch assy. The cost in minimumal (well under $150) for what it does for what it does for your engine. I started having it done when I had problems with a '35PJ engine that had vibration troubles. There aren't many things more satisfying than a very smooth idle!!

[jd52cranbrook]

Good point about the smooth idle and vibration. The cost is a bit over the 150, which doesn't bother me too much. Everything is going up it seems. I see the machinist Monday, he explained it to me once how it's done but I'm going to get more clarification.

[Olddaddy]

In my humble opinion, based upon 36 years building engines.......balance it! Balance every piece that rotates, or is attached to something that rotates. This will free up rpm and hp and will minimize wear from vibration. It is the single thing I insist on for every engine I do.

[PatS....]

At what point does the balance get done? While the engine is out? Or in the car?

HOW is it done?

[greg g]

Pieces parts, pistons are weighed and compared, as are rods, lifters, cranks are checked, flywheel, pressure plate. Basically anything that rotates or reciprocates.

[PatS....]

OK, so now that the head and pan are on, it's kinda way too late!

Next time:eek:

[greg g]

UH HUH, mebbie nextime

[PatS....]

I kept the original engine...I tink its too far gone, but I'll have the machine shop take a look anyway. If it's good to go, then it'll all get balanced. Might as well if it will prevent some vibration on the old girl.

Broken valve, all head bolts broken off, rusty inside...maybe not good for rebuilding.

[Rodney Bullock]

I was told the same thing, I don't know why The v8 machinist did not insist on balancing everything. I think because I got all new stuff it was weighted and compared before it left the factory. On my Studebaker motor the entleman asked me if I wanted it balanced and I told him yes, he said they weight the pistons and rods and the crank, when everything is correct the smoothe excelaration that you get a long with the idle is going to make the motor last a long time.

[jd52cranbrook]

Thanks for all the info, appreciate it.

[randroid]

Gents,

I once wrenched on the periphery of NASCAR and found that those guys balance their engines to half a gram in hopes of making it 500 miles, so when it came time to get the engine in Pigiron running I thought I had some money and took it to a machine shop. The machinist got the entire enchilada to within those tolerances and it is theoretically a 500K engine, and I have receipts for $2700 in machine work alone to prove it.

I don't have 500K miles left in me and I wouldn't want to drive them if I did, and to top that off everytime I lift the hood when the engine's running the first thing I do is look around for the welding leads because it is, after all, an industrial engine. But that puppy is sweet to drive.

I have always admitted that money wasn't wisely spend, especially when I remember I could have bought three rebuilt short blocks from Checker for the same price and had a good chunck of changed left over, but I have a NASCAR-spec 218.5 ci flathead six pushing my drive and although the car itself is uglier than a sack of @$$h01e$ (is that cryptic enough?) I sometimes just like to hear it run.

Get it balanced? The old air-cooled VW engines had a great reputation for staying together, and factory specs was balanced to 5 grams so it isn't always necessary to get things just right, but the closer you get the more snide you may act in the company of your peers.

Have a machine shop do the crank, camshaft, flywheel, and pressure plate. You can do the pistons and rods yourself; it doesn't really matter what they weigh as long as they are close to each other.

I didn't miss what you said about not getting it done at this time, but you've heard several idiologies on the subject and I wanted to interject the vagrant ravings of a madman.

-Randy

[norrism1]

PatS, If you decide to rebuild the engine. Have the shop put in hardend valve seats like the B series trucks have. Benefit is unleaded can be used with no additive and with a triple grind on the valves and seat you will get better sealing with the valves. It will also fix the valve seat crud you have in the picture.

[Plymouthy Adams]

These engine already have the hardened valve seat, the advantage truck engines have is the positive valve rotator..and sodium filled valves.

[norrism1]

These engine already have the hardened valve seat, the advantage truck engines have is the positive valve rotator..and sodium filled valves.

Tim, Sodium valves are used on the engines with fluid drive tranny. Possibly on the long frames too. What is the positive valve rotator, never saw one on my B3B.

[jd52cranbrook]

Droped everything off there today for the balance. Smoot ride with great torque sounds nice.