mianne

My Feedback: (3)

anyone use a piston stopper .will this damage the piston

Anthoop

I would never recommend using one.

1QwkSport2.5r

Never seen one to fit a 1/4"-32 hole, even if I had I wouldn't use one either.

i8tweety

My Feedback: (11)

I use them on both my nitro and gas engines and have for decades. I use them for all my engines including high end nitro .21 buggy and on-road engines ($500 engines) and full mod zenoahs, M&D cast motors, and QuickDraw motors for my boats. The key is to not over tighten you crank nut.

downunder

Personally I think they're the Devil's tool...or at least designed by someone wanting to sell new piston/liners. You've got a rod less than 1/4" diameter sitting right over the weakest part of the piston crown and a gorilla turning a wrench on the crankshaft nut. Even if you don't punch a hole right through the piston you could certainly deform it. If you really must use one then the safest way is with the piston halfway along the stroke. That puts the rod at right angles to the crankshaft and gives the least leverage (pressure) on the piston.

A better way is with the engine inverted and the cylinder half filled with fuel to give a hydraulic lock. That way at least all the pressure is transferred evenly across the whole piston crown instead of being concentrated. An even better way would be to use a leather strap spanner, kind of a small version of what's used to remove an oil filter from a car, to hold the flywheel itself. Some heli guys remove the backplate and use a tool that locks the crankshaft or remove the carby and fit a wood or plastic dowel through the crankshaft port.

savagecommander

nylon rope

mianne

My Feedback: (3)

im trying to tighting the flywheel nut.i was told to use a piston stopper but other people told me I can do damage to the piston.whats the best way

i8tweety

My Feedback: (11)

For tightening the flywheel nut, I use my piston locking tool until it is snug. You do not have to over torque this, just make it snug. If you feel the urge to over tighten, once snug, use a pair of channel locks on the flywheel to hold the crank still those tightening further.

For those speaking ill of piston lock tools, have they ever witnessed damage caused by one? They are made from cheap aluminum and tend to deform first when one over tightens.

mianne

My Feedback: (3)

im just gonna use the plires on the flywheel this is a brand new lrp 32 and I cant take the chance on doing damage to the piston

i8tweety

My Feedback: (11)

If you're going that route, use tape, elastic bands, etc over the flywheel to prevent it from getting marred or gouged

mianne

My Feedback: (3)

well I can do that what else can I use to do this

flycatch

My Feedback: (26)

You don't want one. Purchase a crank stopper used by the helicopter community.

SeaJay

My Feedback: (6)

I would take out the glow plug and put some cotton string or twine through the hole into the combustion chamber at least untill 1/2 - 3/4 full, then use that as your piston stopper, as that will spread the pressure across the entire piston, similar to the hydro lock described earlier, but without all the Mess! 

tenacious101010

My Feedback: (97)

Nylon 1/4 inch rope, cheap and will not damage engine. Mentioned earlier, have used it on many types of engines. Heres a step-by-step proceedure.
1. Remove spark plug
2. Rotate crank to move piston down towards bottom dead center (approximately).
3. Feed in the 1/4 inch rope, filling the combustion space leaving several inches of the rope hanging out the spark plug hole.
4. Rotate the crankshaft with your wrench and it will compress the rope and prevent the piston from moving up as you tighten or loosen the nut.
5. Remove rope when maintenance completed.

No better way to prevent possible damage, even to spark plug threads.

Airplanes400

My Feedback: (349)

????

Airplanes400

My Feedback: (349)

Why would you want to duplicate or inflict the symptoms of an enlarged prostate upon yourself?

RCer22

Don't use a piston stopper. There are more commonly knew as a piston punch. Because that's what they can do. Punch a hole right through your piston.
Better off taking the back plate off and using a crank stop. Get a nice safe plastic crank stop from your LHS or favorite online store.
Get the one designed for your size engine. They usually fit more than one engine. It should part of your engine tools. You wouldn't use a pliers to change a glow plug would you? You would use a glow plug socket.
BTW I hope you don't need a crank stop to remove your prop nut. If you do then you're making it way too tight.

mianne

My Feedback: (3)

no I was gonna use it to put my clutch nut on the flywheel

Insanity99

I've got a piston stopper and haven't had any issues yet. But recently I've been using a pair of channel locks to hold the flywheel. I don't care if the flywheel gets marred as I use a screw driver end to stop the motor anyways.

Tony Iannucelli

My Feedback: (193)

One method is a crank stop tool. You need to remove the backplate. The tool holds the crank in a vertical position and you tighten the nut hard as you please.
A second is to pull the carb and insert half a wooden close pin or a 1/4 dowel in the intake port on the crank. Tighten away.
I've used the stopper and as the other guys said, don't overtighten. I've put some foam tape on the tip of mine to avoid scratches.
Good luck, go easy. Tony

Anthoop

That is a nice safe idea, never thought of that...thanks.

I have never seen one cause damage but I have never used one. For me it is the principle of the thing, sure we know not to tighten the flywheel nut like a gorilla...but does everyone?
I would disagree that the cheap aluminium would deform before you would/could damage the piston.
Personally I have always tightened the flywheel nut by holding the flywheel.

Insanity99

To me it seems like a lot of extra work to tighten a flywheel buy removing the carb or back plate.

mianne

My Feedback: (3)

me to.and I cant see putting a rope or clothes pin in the motor to lock it up.pliers holding the flywheel works for me.my buddy put a clothes pin in the muffler port witch worked.but the clothes pin left wood chips in the motor.not for me.ill stick with the pliers

Anthoop

It is one bolt to remove the carb.