Straight edge tolerance.

[chapel gate]

Can someone confirm if a 750mm grade 2 straight edge is good enough for cylinder head work?

I think/hope it is.

Having a bit of imperial/metric conflict going on..

Ta.

 

[Iwan]

The straight edge that I used was 40 x 8 x 1000mm but at 750mm a 35 x 7mm would be the right dims for the length.. so if it's 7mm or more then it's adequate with DIN 874.

If you want a 2000mm long edge then you would be looking at 60 x 12mm DIN 874.

From what I worked out a while back... the head wasnt straight so I had it skimmed, new valve guides especially on the exhaust valves more needed than the intakes, guide seals and tappets adjusted and rectified. Ready to fit on the 12v 1hdt.

Also worth checking the length of the exhaust valve springs as mine were too short, used 1kzt valve springs instead same part number.

 

[chapel gate]

mines 40 x 8.

inbetween building gravitrax with little lad, i managed to do a bit of searching. not being familiar with this DIN standard, finding that grade 2 was the lowest alarm bells rang.
turns out grade 2 at 500mm is accurate to 21 microns-0.021mm-0.0008".

max head warpage is 0.20mm-0.0079"

we seem to be all good..

 

[Iwan]

There also an indentation where the head overhangs the block. The fella at the machine shop said that it's a guide to see if the head has previously been skimmed before or has been skimmed to the max depth..

I told him that I had bought the block without a head and He suggested to suspend the engine with the sump off and turn it over with the starter motor holding a bowl of new oil under the strainer and check that there's steady/consistent oil flow out of all of the relevant areas on the crankshaft. Sounds messy but I'm going to give it a go!