1933 Harley-Davidson VL Build: Preparing the Cases

[BigLakeBob]

(next time you come in from the garage try washing your hands using only straight tap water). However, if your friend's parts had little or no oil trapped in cracks or pores to begin with, boiling them in straight water could have removed surface dirt (which might well have had oil mixed with it, making the part look oily) and made them cleaner and easier to weld so this would have been the effect he reported to you. But, I suspect if you ask your friend for details he will report back to you that he used soapy water in his turkey fryer.

I'm not sure if he used any soap or not, I need to ask him. As far as the washing your hands comparision, I never washed my hands in 212* boiling water without soap, so its hard for me to agree if my hands would become clean or not. The last item he did was a set of 57 Pan cases that were cracked at the rear motor mount, and as I said he had good welding results. Next time I talk to him I'll ask. Anyway, maybe its a starting method for someone here to elaborate on and hopefully work for their own circumstance. Bob

[BoschZEV]

As far as the washing your hands comparision, I never washed my hands in 212* boiling water without soap, so its hard for me to agree if my hands would become clean or not.

I'm pretty sure you know the answer to this. Oil doesn't dissolve in water at 212oF any better than it does at the ~125oF of the dishwasher. If it did, you wouldn't have to use detergent in a dishwasher to get the grease off the pots and pans.

If the rear motor mount involved welding a lug that was totally external to the engine, and thus only covered with the usual mud and oil the outside of an engine collects, it's possible straight boiling water might have been good enough in that particular case. But, since you know soapy water removes grease (and dirt) better than straight water, why would you ever choose to use straight water? Even if they only had dirt on them, not many people would choose to wash their hands only with water if they had the choice of also using soap. Or wash their car with straight water, rather than water plus soap. Soap isn't used for purposes like this just out of habit, it's used because it works better than water alone.

[Peter Cooke]

p.s. this thread started out as a build but nothing has been posted for nearly two months. Has it hit a roadblock, or is it still ongoing and the builder too busy to update it?

It's still alive over on the riding vintage website. Maybe the 'to blast or not to blast' discussions have put him off updating it here.

http://www.ridingvintage.com/2014/01...vidson-vl.html

[BoschZEV]

Maybe the 'to blast or not to blast' discussions have put him off updating it here.

That's too bad. But I see the discussion didn't put him off continuing to blast everything.

[BigLakeBob]

It's still alive over on the riding vintage website. Maybe the 'to blast or not to blast' discussions have put him off updating it here.

http://www.ridingvintage.com/2014/01...vidson-vl.html

If that's the case, I apoligize for being part of that discussion and causing that. Next time I'll sit back and just enjoy the ride. Bob Rice #6738

[duffeycycles]

my friend soaked in old time carb cleaner 5 gallon can ,nasty can first, a few days later, less nasty can and then the cleanest can,scrubbing a little each can change..Then he boiled in water..welded many cases in his 40 years at it

[sirhrmechanic]

I should have mentioned this before... but back at the "old" shop (before we moved) crankcases, etc. were cleaned by soaking in a witches brew of chemicals offhandedly referred to as "Carb Cleaner" but probably something far more sinister. Or maybe carb cleaner back in the day was made of things that would give you two-headed kids. The container was an old garbage dumpster which had been sealed by welding any kind of fissure, seam, crack or hole. The chemical mix was 'sealed' by a layer of 6" of water floating on it. Every now and then, you poured in some water and it all settled out again. So whatever the actual chemical was had a specific gravity greater than water. Parts were lowered into the tank with an electric chainfall and left for a couple of weeks and they came out clean like you can't believe. We could put whole engines inside (undismantled) and they came out really easy to dismantle.... The tank had been 'filled' probably in the 1980's... and all I know of it was that the toxic waste disposal company that emptied it and took it away when we moved locations charged us about $5K for the disposal. We opted not to deal with refilling it and actually left the tank at the old building. But damn it worked well.

Cheers,

Sirhr

[Peter Cooke]

If that's the case, I apoligize for being part of that discussion and causing that. Next time I'll sit back and just enjoy the ride. Bob Rice #6738

I don't think an apology is necessary Bob. Everyone's allowed an opinion. I actually found it a very useful thread as I'll soon be starting on my 31V and have now decided that blasting of any description will not be used on the crankcase halves. I've also done some research on companies doing Vacuum Impregnating here in Melbourne.
The one I'm looking at provides the following info on there website;
"The process uses ULTRASEAL PC504/66 Methacrylate Sealant, which once set can operate at temperatures between -50 to 200 degrees Celsius".

200 C equates to 392 F. I'm assuming that's more than enough to accommodate the crank case temps??

Also, with VI I believe I'd need to remove all the bronze bushes for the cam and crank. I suspect sealing them is not a good idea??

[sirhrmechanic]

Peter:

Yes, you need to strip cases completely bare and they need to be really clean as the VI will 'seal' in stains. You will have no problem re-fitting bushes, sleeves, guides, etc. though you may have to do some careful surface cleaning or lapping of tapers, etc. simply to remove any thin surface deposits of acrylic. The stuff does not coat the casting, it's inside the pores. But that doesnt' mean that you can't get some spots on the surface (especially in holes or recesses) where a thin layer remains behind. For example, when we do car crankcases, the bearing saddles generally have to be polished out with Scotchbrite or 600 grit after the VI. And when I put valve guides into heads, I usually do a fine lap to get the 'height' right before knocking them in on their taper.

But anything left in a casting before VI... including studs, guides, bushes, etc... will have to be machined out after VI.

Cheers,

Sirhr

[BoschZEV]

I've also done some research on companies doing Vacuum Impregnating here in Melbourne.

One thing that hasn't been mentioned, that you should carefully consider, is that if you do vacuum impregnate something and then later need to weld it near where the resin filled a crack or surface porosity, you will find it extraordinarily difficult if not impossible. It's not unlike the problem faced by all sorts of people who coated their gas tanks with miracle sealers in the past, and who later found when ethanol fuels were introduced that it attacked the coatings. At the time they coated their tanks it might have seemed like a reasonable alternative to "properly" fixing the crack, but any chemical "fix" (vacuum impregnation, JB weld, duct tape, ...) has a finite life and the risk of future incompatibilities that often can't be foreseen.

If you have a high value vehicle that will see little use so it has small chance of needing to be rebuilt again in the future, vacuum impregnation of the cases might be reasonable to help keep the garage floor clean. However, most motorcycles -- especially ones that are used -- are going to leak from the gasket surfaces and oil seals anyway, so the benefit of stopping the small additional leakage from possible microcracks has to be weighed against the cost of eliminating the possibility of welding in the future.

The bike is yours, so the decision is yours, but make it knowing that there are plusses and minuses to doing this.

[Peter Cooke]

Thanks gents, that's more useful information to be taken into consideration.