Using solder for squish gap measurement

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LC Cnd
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Using solder for squish gap measurement

#1 Post by LC Cnd » Sat Mar 31, 2018 9:29 pm

Found this way to measure squish and wondered if what type of solder is best used. Suspect not acid core.

"You measure the gap by taking out both spark plugs and poking some solder into the squish gap, through the spark plug hole and right to the cylinder wall. Turn the engine gently with the kick-start: The piston will squash the solder to the width of the squish gap. You then take out the solder and measure how wide it is with a vernier gauge."
Last edited by LC Cnd on Sun Apr 01, 2018 2:25 am, edited 1 time in total.

tacky1
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Re: Using solder for squish gap measurement

#2 Post by tacky1 » Sat Mar 31, 2018 10:00 pm

I just use regular plumbers solder you buy at the hardware store, Works great
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LC Cnd
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Re: Using solder for squish gap measurement

#3 Post by LC Cnd » Sun Apr 01, 2018 2:26 am

Thx for your input - appreciate it.

RuZty
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Re: Using solder for squish gap measurement

#4 Post by RuZty » Sun Apr 01, 2018 4:53 am

I've always used 2 pieces in a cross to get both sides and front/back. A bit of tape or Plasticine in middle to hold it in place while the head goes back on. If you don't want to remove the head first at least try to get 2 pieces bent so you can get front and back at the same time so you are taking piston rock out of the equation.

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Re: Using solder for squish gap measurement

#5 Post by evan_calgary » Sun Apr 01, 2018 12:13 pm

Standard solid solder will work. As suggested, cross the pieces and make sure they go right to the edges of the barrels. Don't rotate the engine all the way or you may cut off the ends of the solder on the ports then have to fish out of bottom end. Done that before. Pretty easy job. Rotate back and forth near TDC a number of times to ensure totally squished and take head off and you are done.

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Re: Using solder for squish gap measurement

#6 Post by T.RexRacing » Sun Apr 01, 2018 2:40 pm

I use standard solder fashioned into a square anchored w/dab of bearing grease so I cover four directions from center. I do give the head a thin coat of oil to ease the squeeze and prevent sticking to chamber.
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LC Cnd
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Re: Using solder for squish gap measurement

#7 Post by LC Cnd » Mon Apr 02, 2018 12:21 pm

Lubricating the solder - very good point. So, the lengths of the solder that are bent for exposure to TDC should be about 3 to 4mm - is that enough depth front and back?

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Re: Using solder for squish gap measurement

#8 Post by evan_calgary » Mon Apr 02, 2018 9:03 pm

The lengths should slightly wider than the diameter of the barrel to allow you to twist them in the middle. Or are you planning on making an X with bent ends (cue the Reich jokes)? you are making a "X" and ensuring it goes all the way to the edges of the barrel. You end up with 4 measurements, one at each 90 degrees of the barrel. It's a soft metal, lubricate it if you want but it is entirely un-necessary.

LC Cnd
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Re: Using solder for squish gap measurement

#9 Post by LC Cnd » Tue Apr 03, 2018 1:08 am

Thx for your insights one and all - can't wait to try this. Awesome form as always.

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