Big bore kits

[mack]

As some of you may know, I bought a seized 78 E to restore. I got it down to the jugs now and found the pistons are rust welded to the sleeves. Not sure if trbigs tool, will work to get the jugs off. I really want to save the upper crank case with the serial number on it. Was thinking that perhaps I shouldn't give up on this one yet. While the pistons and sleeves are shot maybe it could be a candidate for a big bore kit. However I know nothing about what would be involved. If the pistons are larger, do you have to machine the head's combustion chambers to accommodate?

[crazy steve]

Mack, you might try putting diesel oil in the bores and see if that will free up the pistons; I've had good luck with that...

As to an overbore, you don't need to do anything to the head. The larger bore will increase the compression ratio to about 10.5:1, but that will help with both power and efficiency. It will require premium fuel all the time though; no sneaking lower-grade fuel in....

[jwhughes3]

Try Kroil from Amazon....supposed to dissolve rust crystals.


John

[mack]

Rust

Kind of knew I was in trouble when I pulled the head off and found this.

#1 is on the right side of the picture. It's about three inches below #2 but the sleeve is full of water, rust and what ever else had been put in by the PO to free them up. I used a turkey baster to suck out the sludge but man, stink!!! Large chunks of rust larger than a shot glass were just sitting in the sludge. I took a spoon and scooped the crap out of all them, then used a puddy knife to clean the sides as best I could and used the spoon again to clean that out.
I couldn't tolerate the smell anymore and had to give up. Going to make Trbigs tool and and I'll try filling the sleeves with "metal rescue" for a few days while I let the shop air out.
Steve I've heard that diesel works pretty good as a penetrating fluid and once I have the surface rust and sludge taken care of in the sleeves I'll have a better chance of the diesel making it to the portions I can't get to. This with some upward pressure for the tool may work.
Nothing was moving and I couldn't get to the cam sprocket nuts so I wound up having to snap the chain to get the cams out and head off. I'm taking lots of pictures and will post them in a cohesive order in the near future.

[jwhughes3]

http://www.kanolabs.com/


John

[crazy steve]

Fill each cylinder to the top with diesel and let it sit until you see the level drop; at that point you know it's crept around the rings. If it still won't turn, then try 'bumping' the pistons around their edges with a piece of wood to free them up. The only ones that I've seen this wouldn't work on were rusted so heavily that there were deep pits in the bore...

If all else fails, rather than try to remove the cylinders with the pistons still seized, I'd split the cases and remove all the rod caps, then pull the pistons/cylinder as an assembly. Then you can beat the individual pistons out fairly easily...

[BA80]

Being that nasty I don't think the rings would ever free up. IMHO

Best just pull it down and do it right.

[tarzan]

If it looks like that on top, it probably ain't much better in the bottom end.

[mack]

Not sure

if we even have Kriol here in Canada. Too many tree huggers. The PO of this machine had left the plugs out for years. He didn't know too much about this bike, for instance that it had a kick starter lever or that there was an oil drain bolt. He drained the oil by removing the oil filter cap. So when I drained the oil the crank case was almost filled to the top. As such I'm pretty confident the lower portion of the motor is ok, at least the clutch side looks good. Youngest daughters B-day today so I won't get any work on it today, shop still stinks anyway. I'll take my time and get this corrected. Want to save as many parts as I can for other members to use as needed.

[jetmechmarty]

I'm anxious to see if that Metal Rescue will free it up. I have a bottle and a stuck engine and I haven't got around to trying it. I saw the Metal Rescue people at the Barber Vintage Fest and they swear it will free a stuck motor and call them if it doesn't.

[Schming]

Penatrants- Borrowed from STF

"FYI Penetrating Oils

This actually works well, power steering fluid also works as well as trans fluid!

Penetrating Oils
Machinist's Workshop MagT recently published some information on various penetrating oils that I found very interesting.
Some of you might appreciate this. The magazine reports they tested penetrates for break out torque on rusted nuts.

They are below, as forwarded by an ex-student and professional machinist. They arranged a subjective test of all the popular penetrates with the control being the torque required to remove the nut from a "scientifically rusted" environment.

*Penetrating oils ........... Average torque load to loosen*

No Oil used ................... 516 pounds
WD-40 ..................... ... 238 pounds
PB Blaster .................... 214 pounds
Liquid Wrench ...............127 pounds
Kano Kroil .................... 106 pounds
ATF*-Acetone mix............53 pounds

The ATF-Acetone mix is a "home brew" mix of 50 - 50 automatic transmission fluid and acetone. Note this "home brew" released bolts better than any commercial product in this one particular test.

Our local machinist group mixed up a batch and we all now use it with equally good results.
Note also that "Liquid Wrench" is almost as good as "Kroil"
for about 20% of the price.

Steve from Godwin-Singer says that ATF-Acetone mix is best,
but you can also use ATF and lacquer thinner in a 50-50 mix.
*ATF=Automatic Transmission Fluid"

[GLoweVA]

I've tried the ATF and acetone mix before and it does seem to work better than PB Blaster.
My only advice wrt the mix is to not leave it in the spray bottle if possible.
As the temperature changed (like summertime heat), the acetone expanded/vaporized, causing pressure to build up in the spray bottle and thus forcing the ATF mix up and out of the nozzle. I had a little puddle under the bottle in a few days.

[MPittma100]

Since All Else Has Failed......

Clean up all of that mess the best you can. Then use a propane torch in each hole heating pistons and bores. Afterwards, pour in your penetrating fluid of choice. Let it soak overnight or at least a few hours. Try turning engine over. If no results, heat again and try turning engine while applying heat. They will eventually break free. You just have to be persistent.

MP

[trbig]

As to your original question... A big bore kit consists of having to bore/hone the cylinders. My guy charges $50 a hole, but some say they found cheaper. I would buy new bearings for the conrods and crank. Basically, you're talking some fairly decent money that I would personally only spend on a known GOOD motor.

Since the motor numbers aren't stamped on the cylinders, my suggestion to you is to do as Steve said.. Split the cases, undo the rods, get those cylinders off with the pistons still in them and try to get them out from there.

Just my 2 cents... find another used motor and use that one for bottom end parts. Or.. find some low-mileage pistons/cylinders to slap to that one if you're just set on using it.

[mack]

Jugs are off

With X-mas around the corner I haven't been spending much time on this restore. I have got the jugs off and finally today was able to press the two siezed pistons out. The sleeves have an obvious ring in them from the rust and I suspect pitting under them. I managed to get the upper case off intact and it looks in good shape so at this p-oint I'm pretty happy.
1. My question again concerns the big bore kits. How much honing would be done to accomodate an 1196 verses say 1147. If I find the sleeves are pitted would the honing for the larger kit take off enough to negate the pitting is where I'm going with this.
2. Are these kits all high compression racing type kits. If so, what other considerations must be accounted for after instalation? IE tuning, shaft upgrade, starter upgrade, battery cranking amps etc.
3. What types are out there and if anyone has personal knowledge I'd like to here it.