Just Discovered low mileage 71Mach2SS

[71MachIISS]

Hi all, I found a 1000 original mile Mach II SS that still has the original Bridgestone tires on it with little wear, was in barn, problem is motor is stuck, and missing a few parts,
left sidecover and ignition switch, intake boots and mid pipes, cables, and front brake lever, choke lever, and various hardware parts and both mirrors.  Original gold color, seat is near mint, was not exposed to sun but chrome bits need redoing.  Bike was never down.  Wondering if this is a do able project or not.  I got a 500 titan running and back in shape, but this looks like quite a challenge, but cool bike
Thanks for any input
Bruce

[slawsonb]

We're all on here to help with questions and dilemmas. Sounds like your find is worth saving. The motor can be unstuck. There are several threads on here about how to undertake that. The bits you are missing are available from the site owner Richard. See the "Click here for parts" button to find his contact info. There are also several site members who list parts in the classifieds and, of course, there's always ebay. It will be some serious work, but these are very cool bikes and a strong running 175 BS will run circles around lots of bigger bikes. Good luck with your project, welcome to the site, and fire away with the questions.
...bert

[71MachIISS]

Thanks for the encouragement. Also noticed I'm missing the trans shift lever.
Adding couple pics. Oil sight glass is dry I hope that this isn't why the engine is locked up
Any comments on restoring bits is appreciated.
Thanks
Bruce

[slawsonb]

Looks to me like, aside from getting the motor lock resolved and re plumbing the intakes, all this one needs is a really good cleaning and some lever/cable repair. I'm a fan of keeping them original if the condition allows. There are 3 basic potential causes of the motor lock. 1. Piston (or pistons) frozen in the bore (s). 2. Stuck crank bearing(s) 3. Stuck transmission. Check to see if the trans shifts. If you pull the heads and get a look in the bores, this will give you insight into whether the source of the lock is in the bores or bottom end. For good measure soak the piston tops and bores with some penetrating oil (use your weapon of choice). In some miraculous cases this will be enough to loosen things up. You're going to want to get some lubrication in there asap anyway.
...bert

[paul]

Side panel and select shift lever should be readily available.  Congratulations, based on assembled quantities you may have the least common Bridgestone.

[71MachIISS]

Hi all pulled heads off. Left side is seized and has pitting on cylinder wall. Right side is smooth and like new.
I took pipe off and squirted ph blaster in there and the top as well over last few weeks.
What do I do now? Bang it down with wooden mallet or torch the sucker then bang it. I expect piston and cylinder are a loss at this point. Thanks
Bruce.

[slawsonb]

Keep up the soaking. My first step would be to get a large wooden dowel and placing it at the center of the stuck piston tap with a hammer. If any movement is detected, continue the process of soaking and tapping as it is likely the cylinder can be salvaged. It will need to be replated (Nicasil...threads on here about this) and maybe repaired depending on how much "convincing" it takes to unstick. Patience and time are your friends. I had one stuck piston that I literally had to drive out with brute force and that cylinder is now repaired/replated and ready to go in the motor I'm building. If you get to the more force stage, there are tricks like splitting the cases to free the crank that may be required, but as I said take it slowly and see where you need to go.
...bert

[bsforever]

ToystoreTom had a thread awhile back ago relating to his 350 on 'stuck piston(s) ...but can relate to any stuck piston for the most part --> http://bridgestonemotorcycleparts.com/index.php?topic=772.0

[dcr]

Beating on the top of a stuck piston can have more impact (pardon the pun) than you may originally desire. The rod, bearings and crank end up absorbing a lot of the force and this tends to create more issues to fix.

One solution is to unbolt the cylinder from the motor and lift up on it as you tap the top of the piston. There are several threads here that discuss this more indepth.

Dan

[slawsonb]

I always split the cases to free the crank and avoid the issues dcr has pointed out, BEFORE any "beating".
...bert

Thought maybe I should elaborate on the case splitting idea. When the lower case is removed the crank and mains are free to drop out of the upper case, but probably will not due to the piston(s) being stuck. I place the upper case/cylinders/crank(and stuff attached to the crank) on 2 2x4's on the outer edges of the case creating clearance below the crank journals. Now when the tapping (maybe progressing to beating) happens the piston pin and bearing, crank pin and bearing, and the main bearings do not absorb any of the load from the driving process. I built one of ToystoreTom's tools using a 1/4 tool steel plate and grade 8 bolts and nuts and tried his approach, but on a VERY stuck piston you may (as I did) just ruin the tool trying to get the piston to move. This process is tricky and everyone has their favorite approach, but take your time and you'll have success. Then you just make friends with a replater/repairer.
...bert

Oh yeah. One other advantage of splitting the cases is that you can get penetrant to the bottom of the ring/cylinder interface. By simply turning the upper case/cylinder/crank assembly over (piston crowns down) you can soak the stuckness from the bottom.
...bert

[71MachIISS]

Thanks to all, the motor is still in the bike.  I will try the gentler
Methods for the moment before resorting to massive crankcase surgery.
At least piston is not at tdc so the rod is angled and should tolerate some movement without
Transferring energy straight to bearings.

[71MachIISS]

Well, I am willing to sell this bike for a fair price or will part out. Original tire wear is minimal, never dropped or buggered and is a bonafide candidate for a masterful restoration. Taking best offer over the next week. Hoping to find a future knowledgeable owner who will do it right.
Thanks for the input I have received.
Bike is in Michigan.
Bruce