Another squish method

[marrcel]

I am trying another method of measuring squish.
My barrel bottom gasket was squashed from 0,8 down to 0,5mm. So that will give 0,3mm less squish.
So now i want to use a fiber gasket. After cutting the gasket to size i sticked a piston in the barrel. After i pushed the piston against the head i measured the distance plughole to piston head. I call this squish 0mm. I used solder wire 1mm to check if the piston lowered 1mm. And it did so no other hitting point in the dome.
I measured the depth to the prox piston head. Left was 31,0mm and right 31,2mm. I don’t no yet if this can be reproduced with engine in the frame. But anyway i share this with you. Any other experiences out there? Yes I mentioned the solder wire.
Here some pics to explain.

[marrcel]

This is the squashed barrel gasket. Newspaper quality?

[marrcel]

The new cut fiber gaskets.

[4l04ever]

Looking good.

Any fibre/paper gasket material will squash down when compressed, the amount depends on the material and the force applied. Some can compress upto 40%, so you have to measure after you have torqued down to see where you are at. If you need thicker than 0.6mm, and don't want too much compression, it may be better to use a spacer plate with 2 thinner gaskets. I needed 1.9mm after getting rid of my head gasket, so run a 1.0mm spacer plate with a .4mm gasket one side and .5mm gasket the other side.

Also bear in mind there is a manufacturing tolerance on most gaskets materials of usually around +/- 10%, so 0.8mm material can be anywhere from .72mm to .88mm to start with before being compressed.

Let us know how this different material goes, but expect some compression, so may need further adjustments.

Keep up the good work.

[marrcel]

Now thats some useful info.
Just installed pistons barrels and head.
For the head i use a torque wrench 2,8kgm.
For the barrel bolts i cant use the wrench. So i use a spanner and i pull with 12kg at the moment. Dont want to squash it too much. I use a digital spring scale. It measures up to 40kg. I used nylock bolts with a washer.
How do you torque up the barrel bolts. Spec is 2,5kgm

[flames]

Mar 7, 2020 21:28:28 GMT 1 4l04ever said:

Looking good.

Any fibre/paper gasket material will squash down when compressed, the amount depends on the material and the force applied. Some can compress upto 40%, so you have to measure after you have torqued down to see where you are at. If you need thicker than 0.6mm, and don't want too much compression, it may be better to use a spacer plate with 2 thinner gaskets. I needed 1.9mm after getting rid of my head gasket, so run a 1.0mm spacer plate with a .4mm gasket one side and .5mm gasket the other side.

Also bear in mind there is a manufacturing tolerance on most gaskets materials of usually around +/- 10%, so 0.8mm material can be anywhere from .72mm to .88mm to start with before being compressed.

Let us know how this different material goes, but expect some compression, so may need further adjustments.

Keep up the good work.

What do you use for your spacer? and do you make them yourself?

I have a set of barrels that had the the top skimmed and ran a spacer between 2 gaskets but i long ago lost the spacer.

The above seems like a great method to work out how thick a spacer and gaskets i would need to get the squish right.

Sorry for going off subject.

[4l04ever]

I made my own spacers, but someone on ebay sells them in various thicknesses.

[flames]

Jun 18, 2020 18:52:52 GMT 1 4l04ever said:

I made my own spacers, but someone on ebay sells them in various thicknesses.

Cool. Thanks.

[reedpete]

There are many ways to measure things but generally the preferred methods focus on measuring things directly, measuring things indirectly Ie one measurement plus/less another means that the measurement errors of each first measurement will appear in the Dimensions of interest.
So, whilst what you’ve done will give you a good indication of the squish gap a direct Method would always be preferred if possible.

[midlifecrisisrd]

Mar 8, 2020 8:37:02 GMT 1 marrcel said:

Now thats some useful info.
Just installed pistons barrels and head.
For the head i use a torque wrench 2,8kgm.
For the barrel bolts i cant use the wrench. So i use a spanner and i pull with 12kg at the moment. Dont want to squash it too much. I use a digital spring scale. It measures up to 40kg. I used nylock bolts with a washer.
How do you torque up the barrel bolts. Spec is 2,5kgm

NK racing does a spanner with a 12mm on one side and a 14mm on the other

There is a 3/8 square in the centre for your wrench to go on and a calculation for adjusting the wrench torque setting to compensate for the extra leverage

Alternatively a spanner and 4 open fingers on it tightening as much as you can

Your spring scale method is the same idea but more accurate

Steve

[JonW]

Jun 24, 2020 22:17:17 GMT 1 midlifecrisisrd said:

Mar 8, 2020 8:37:02 GMT 1 marrcel said:

Now thats some useful info.
Just installed pistons barrels and head.
For the head i use a torque wrench 2,8kgm.
For the barrel bolts i cant use the wrench. So i use a spanner and i pull with 12kg at the moment. Dont want to squash it too much. I use a digital spring scale. It measures up to 40kg. I used nylock bolts with a washer.
How do you torque up the barrel bolts. Spec is 2,5kgm

NK racing does a spanner with a 12mm on one side and a 14mm on the other

There is a 3/8 square in the centre for your wrench to go on and a calculation for adjusting the wrench torque setting to compensate for the extra leverage

Alternatively a spanner and 4 open fingers on it tightening as much as you can

Your spring scale method is the same idea but more accurate

Steve

Motion pro do one like that Steve:

www.motionpro.com/product/08-0134

[earthman]

Squish methods?? Did many owners even do this back in the day? I don't think that I had even heard of it until I joined here or maybe I just forgot.

I've never had to rebuild an LC's top end, back in the day a mate kept blowing up his 125LC, I doubt that he knew about this either, maybe that's why he had to keep working on it? Lol