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MG Midget and Sprite Technical - Measuring Cyl Head Volume

Just a quick one when measuring combustion chamber volume in the Cylinder Head. What fluid have you found gets the best results? Obviously all fluids have a certain amount of surface tension and do not lie perfectly flat but curve. I was going to use Kerosene or Diesel but have heard of people using Water/Alcohol mix (not my preference)
Any ideas from experience welcomed.
Ed H

Methylated Spirit is an option
Alan Anstead

I've found using a petroleum based mix in a 30cc plastic syringe quickly damages the O ring seal as well as wiping out the graduations.I now just use water,but with a perspex lid and a smear of Vaseline.If you then use it on an angle with a tiny hole at the highest point,trapped air can escape as you add the last drop. I repeat each chamber 3 times for confirmation. Alternatively I have used Plasticine as the fill medium.

Water and a couple of drops of detergent. But clean & dry straight away then coat with WD40 etc and wipe off the surplus.
Paul Walbran

I used linseed oil putty. Its cheap and packs in well so no voids and then you slice the surplus off with a flat blade
Guy W

I used the tail end of a bottle of red wine, along with a cd case lid. The colour helps to show up whats going on. Its a bit of a fiddle to get the trapped air away from the edges. As suggested, seal the case lid with a smear of vasaline. Clamp it on with a g-clamp or a valve spring compressor, then you can jiggle the head about to encourage the bubbles out.
I bought a burette from a schools supply company on the net. Glass, so the graduations don't rub off, and its marked in tenths of a millilitre. About 15 IIRC.

M Crossley

I used red wine too, along with some cheese and biscuits. ;).
Lawrence Slater

What type of cheese, I'm struggling to get my cheddar in the Burette.
Joking aside thanks guys I'll have a go this weekend.
Ed H

Seriously, I experimented using margarine, but it was difficult to scrape it all out again to measure the amount. That's when I tried putty which just holds together better in a ball when you remove it.
Guy W

Liquid cheese Ed. lol.

Top prize for adapting food for various purposes, must go to Guy. :).
Lawrence Slater

Put the head ad a slight angle and put a sheet of perspex over it sealing it with a thin smear of Vaseline.
Make sure there are 2 holes in the sheet one on the top one just below the other.
The lowest hole should be a tight fit for the tip of the burette the top one is to let the air out so 2mm should be fine.

Since there is a flat surface on top no surface tension so each time perfectly repeatable results.
Onno K

I like blue windex window cleaner the best, its easy to see and has lots of soap and ammonia in it so it dosnt stick to the metal or the plexy glass

Like onno...I drill 2 holes in the plexy and I use a smear of bearing grease ...

On the plexy...becarful where you hold it down, the glass flexs both convex and concave depending where your fingers are appling pressure

I use a wall paper paste syringe...avialable at most professional house paint store and wont require a doctors prescription to purchase

Prop and the Blackhole Midget

This thread was discussed between 05/02/2014 and 06/02/2014

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