Tip of the day series- Make a piston stop-Home garage style

[SUPERTUNE]

Tip of the day series... making a piston stop, garage style.

So, Matt texted me today needing to torque on his Vape (powerdynomo) cdi flywheel bolt.
I did cover this in my CDI install, where I suggest to take off the clutch cover to hold the pinion nut, but he didn't have another side cover gasket as I think he said he glued it on and was running out of transmission oil.
So I said to use a piston stop in the left cylinder then time and torque the rotor bolt in.
This is the one I have for this task...



So I decided to make a piston stop from scratch real quick for a garage down and dirty one in 20 mins...
Matt has a RD350 so I used a old B8HS sparkplug and used my sizzler wheel to grind off the ground strap.



Looked around the shop and found a piece of aluminum thick wall tubing that was 5/16 od in size about 1 1/2 long.
(can use a solid rod too... your going to drill it anyways.)





Put it in my drill press and drilled it out to clear the porcelain...



I used a 7/32nd drill bill and drilled it about 5/8 inch deep, (just looked at it and guessed)



I was in a hurry so I used JB weld quick to paste in the plug and the drilled end on the tube I just drilled and pressed it in tight in the vice.
( use std JB weld and wait overnight)







Make sure you keep the epoxy off the threads...
Let dry and now you have a homemade piston stop!





Chuck

[paul1478]

nice work Macgyver

[m in sc]

.. if i may say (and automotive guys will know this as well), IF you have a motor with canted plug holes, ie: suzuki or some singles,  and/or you dont have a dial gauge, this is helpful to determine TDC.

you put the piston stop in, and rotate motor one way till it stops. mark rotor and make pointer.
rotate back the other way till it stops again, mark again. measure distance between lines, that's tdc. you can, if you need to, use a degree wheel to lay out timing marks.
If anyone has a compass, this is where bisecting 2 arcs can be really handy. (us old school drafting guys remember doing this)

just my .02.

side note:

if you don't feel like cutting up a plug, these are handy for making a dial gauge base or piston stop as well.

plug anti-fouler contraptions from parts store, always on the help aisle. think its dorman # 42008

[Striker1423]

Here's what I came up with after that discussion too. Didn't have pipe laying around and wasn't venturing to the store. But, I do have some 30 carbine brass handy. Punched the primer out, mixed up some two part, epoxy, cleaned the plug and brass a bit. Squished it in and let it dry overnight.

Worked a treat!



Thanks Chuck!

[rodneya]

I have always just pushed a piece of rope down the spark plug hole whenever I have needed a piston stop.

[Old Brit]

I have always just pushed a piece of rope down the spark plug hole whenever I have needed a piston stop.

Yup, me too 👍