Daves 73 Z1 Project

[wilsonsjw11]

Dave
Try putting some heat on the screw with a gas torch then cool it quickly with water then try and remove with an impact driver.If all else fails you will have to drill it out with care.You may as well take it to machine shop and get them to drill out the sheared exhaust studs too.I see all the cylinder studs came out all right.
Dave don't worry about the cost of the bitz it's only money and you have'nt started yet!!!!
Regards
Steve

[Z1parR]

Dave don't worry about the cost of the bitz it's only money and you have'nt started yet!!!!
Regards
Steve

[G]

Good luck Dave , I will follow this with interest

[ZedHead]

I had exactly the same problem with the front cam chain screw. Ended up drilling it out starting off with small drills to 3mm, then removed the head with a 6mm drill. the remaining stud then unscrewed on the end of a 4mm left hand drill... no helicoil needed

[ollie]

looking good Dave ,normally an impact driver will do the trick with heat.Failing that get the drill out ...lol

[DaveZ1]

Cheers Ollie, after using a nice sharp chisel to put a slot in the top of the screw a bit of heat and a flat bit in the impact driver. (And with crossed fingers) it came out a treat
Just got to tackle the exhaust studs next!

[ollie]

good news that you got the sucker out dave ,go easy with those studs mate !!! make sure the missus is out of the way when you start cursing ######

[DaveZ1]

Ok, now to tackle what is probably a common problem with old zed restoration, the dreaded snapped off exhaust studs.
6mm studs are a particular pain because they're dead easy to shear and very hard to get out and most would send them out
to a machine shop to have them drilled and helicoiled hopefully the following solution I found will give others on here an
alternative that can be carried out in your own workshop.
This pic shows a boss that I turned up that fits snuggly into the exhaust port and has two holes drilled precisely where the studs are.
One 6mm to bolt the boss in place using the other studs fixing and a 6.3mm hole which is the tapping size for the helicoil insert.
This drilling jig ensures precise drilling out of the snapped off stud without the drill bit wandering off to the side.






This jig will only work though if the other stud for that exhaust port is removed ok. Luckily only one of mine had both studs sheared.
I also found the best way to stand the head at the right angle to drill the studs vertically was to lock some screws off at the right length in the inlet rubber fixings untill the exhaust studs are straight vertically.





Then ithe 6.3 holes can be drilled, (on a pedestal drill) tapped out and the helicoil inserts fitted to create a new (and stronger) thread for your new exhaust studs





If anyone wants to give this method a go I am more than happy to send the drilling jig out to any club member, Just drop me a pm.

More engine prep work next.

[Pigford]

If your BOSS fits snuggly into the exhaust port recess - then couldn't it be used if you're unlucky enuff to have 2 x studs sheared off

Good stuff by the way

[DaveZ1]

Masked off and put screws in all the tapped holes in the crankcases before sand blasting and painting using warmed up
Simoniz tough Satin Black as reccomended on this forum. Got to say this stuff really covers well and leaves an excellent finish... well impressed!






I used a length of M8 stud with a washer and nut at each end to blank off the main oil gallery, then a light sand blasting to remove the old finish avoiding the inside of the crankcases and after a good blowdown into the paint booth for a couple of coats of fresh Satin paint






Looks almost full gloss when applied but dries to a nice Satin finish



They will be left to cure for a day or two then stoved off in the oven to leave a nice durable finish.
Still got the head and the block to do.

With the frame and swinger now away at the paint shop being I'm off to Hutchy's in the next couple of days to drop my paint set off and collect some bits and bobs.
Getting there slowly

[DaveZ1]

If your BOSS fits snuggly into the exhaust port recess - then couldn't it be used if you're unlucky enuff to have 2 x studs sheared off

Good stuff by the way

Cheers Piggy,

That one fixing screw stops the boss from rotating in the port, I also found that all of the four exhaust ports were a slightly different fit so that one fixing just ensures nothing moves around while your drilling.

[nealblath]

great job Dave............makes me want to start another Z1 asap

[Ginger Bear]

Excellent method/tips on repairing those exhaust studs.

[ollie]

coming along really well Dave ,like the invention too

[DaveZ1]

A Little more progress to post, but it seems like slow going... Got the frame and swinger back from Northumbria Coatings
and I am very impressed at the job they have done. Sandblasted back to bare metal and they even masked off the threads
and headstock etc. and finished in gloss black. I went for the (more authentic ?) paint rather than powder coating.





I've been trying to get all the bits prepped that are to get re-zincplated and there was quite a bit of the original nuts and bolts
missing or changed to accomodate the US style mods so there is a lot to replace and its easy to overlook something that you
remember during the rebuild.
I must get the crancase bolts sent off so I can start the engine rebuild. Only the rocker cover left to paint but I need to polish the end caps
before I paint it.




Masking off and blanking threaded holes takes most of the time for this job.
Removed the old tyres and stripped down the wheels so the hubs can be painted and polished and the rims sent off for re-chroming . Been thinking about replating
the original spokes and nipples seeing as they're in pretty good shape, has anyone had this done?



There's plenty thickness on the brake disc so a tickle on the ring grinder will only take a few thou off to leave a nice new look finish.



A good look at the wiring harness showed lots of botched scotchlock wiring mods and bad connections causing plugs
and sockets to overheat and burn. Too bad to just repair so a whole new wiring harness from Z-power will be going in this one.







More progress reports coming soon