11 replies to this topic

[MiniElliott]

Hi,

Would anyone be able to tell me if it's capable of skimming a cylinder head and block on a standard mill with a standard face cutting bit ?

My friend works for a machining firm/ blacksmiths and reckons his boss would be able to skim the our blocks for free. However I have only ever heard of blocks and heads being skimmed with a grinding wheel.

 

Is this a viable option providing the mill is large enough ?

My main worry is that the slightly rough surface finish might cause head gasket problems. 

 

Thanks

Elliott

[mini13]

Yes, lots of blocks get done like this

[jaydee]

You can do that, but have to leave a minimal piston to block clearance

[MiniElliott]

Thanks for the replies.

Does anyone know what the minimum piston to block height should be ? 

[carbon]

Minimum piston-cylinder head clearance depends on the exact spec of the motor. For most units about 10 thou below the face of the block is about right.

 

The slightly ridged finish from the fly-cutter should not be a problem, if done well it may actually help the gasket 'bite' and seal properly between the bores.

[ianclark1275]

having the pistons level with block in DV's opinion is a good thing

 

ive run them +5 thou proud of block before

[mini13]

for 1330 and under I aim for flush, for 73 and 73.5 I am for -5 to -10 thou as the gasket can get close to the piston.

[MiniElliott]

Thanks, the engine is a 1310 using a standard crank. 

[nz_seamless]

for 1330 and under I aim for flush, for 73 and 73.5 I am for -5 to -10 thou as the gasket can get close to the piston.

When you say -5 to -10 do you mean five to ten thou proud of the deck or five to ten lower than the deck face?

[mini13]

lower than the face.

[Cooperman]

I aim for zero to 0.005" block deck to piston crown.

[Vipernoir]

I usually go for .020" below following the advice of some very eminent practitioners.