Packard Forum Index » Pre-War (1899-1942)

I'm trying to rebuild my 27 straight six and the crank shop cant figure out how to remove the crank counter weights. since they have it in another state, I cant examine it myself, so I was hoping some of you could give me some insight to removing the counterweight.
As always thanks and Merry Christmas to each of you!
Barry

I'm assuming it's the same construction as the Eights. It's been discussed here before so a search may be helpful. But in a nutshell, mill out the welds over the bolt heads, then mill off the bolt heads, remove the weights, and then remove the remnants of the bolts. You'll need to make or locate new bolts, secure them in place by welding, and then of course rebalance the assembly. Plan on an extra $200-$300 in costs above and beyond what would be required for a simple crankshaft with the same number of journals.

Thank you! I'll pass the on to them

It appears my crank has no bolt heads, seems there are 3 studs holding the counter weight in place with a punched center. Do we drill out these centers?

Again, I'm assuming the 6 is similar to the 8 in which no bolt heads are visible, the are recessed into the face of the weight and the opening welded over. Not an uncommon construction method, one of Packard's automotive engines used it thru 1950.

This is common enough that I'll bet someone has photos to better explain it.

Dave is correct as I am sure the 27 is the same as my 28 526. I did it my self using a friends large drill press with an air table, once set up it is not that difficult. You need an end mill to drill out the bolt as packard ground off the heads flush with the weights, and the mill bit will leave a flat shoulder for the new bolts. If you need the numbers off the allen head cap screws I bought from Mac Master-Carr I will supply on request. Torque and weld and off to be balanced.

Thank you! I do appreciate everyone's help!
Barry

Here is what I did to remove the counterweights on a 22nd Series 356 engine using a splined screw extractor.
Drilled the bolts to the size specified for the extractor and drove the extractor in with a hammer.
Used a beam type torque wrench to gradually apply forceuntil the bolt broke loose then turned it out. The hex on the extractor was only 5/16" so had to use an impact socket after breaking a standard one.

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Exactly what I'm needed thank you!
I'm also trying to sort out using modern bearings in lieu of Babbitt bearings. Can either of you give me some insight?
Hope you all have a great weekend
Barry

If you're planing a regular diet of speeds in excess of what these cars were designed for, by all means consider inserts and/or high speed ring and pinion or overdrive. I stayed with babbit on my 1934 Eight and with the stock rear axle ratio my comfortable cruising speed is 40-50 mph. My original poured bearings had a service life of 82,000 miles. I've done many thousands of miles touring in this car and honestly, I enjoy avoiding the Interstate highways.

Poured bearings are more gentle on the crankshaft journals due to their ability to imbed particles, the also have more latitude with respect to resizing the crank, and they directly provide the rod thrust faces which require other solutions if going to inserts. But, and a big BUT, is that poured bearings won't give great service life if subjected to a steady diet of today's highway speeds without at least the benefit of overdrive or a high speed rear axle.