Skimming a block

[tedmcedd]

I have an engine block which is original to a car, so I'd like to keep it with the car.
The top deck was rusty, so I sent it to the engine shop. They said it will need 20 thou off to clean up.
Would this be ok?
Would I need to change anything else?

Ed.

[spoon.450]

No..if everything else is standard it will be ok.

[tedmcedd]

Ok, so keep to a standard crnk and rods and I'll be fine!?

It's a 998 block that has also previously been pocketed, so I was planning on using a 1275 head....

[spoon.450]

So, you will have to work out your comp. ratio. This is explained how to do in the Vizard book, or probably previous threads.

[Spider]

They said it will need 20 thou off to clean up.

Respectfully, find another machine shop!

Even a 'real bad one' will usually clean up very nicely at 4 or 5 thou.

[carbon]

Ted,

If you're getting the block skimmed remember to remove the engine ID tag before taking it to the machine shop.

[ianh1968]

... or they might chisel it off and chuck it in the bin, like someone did
with one of mine years ago...


Ian

[tedmcedd]

Oh, fair point about the tag!

Can you get the rivets for them somewhere??

[InimiaD]

Tim at Minimail has the "rivets".

[anis]

I tried several contacts at minimail without any answer.

[anis]

I tried several contacts at minimail without any answer.

[ianh1968]

It's a 998 block that has also previously been pocketed,<SNIP>

The engineering shop aren't quoting an amount to remove the pockets to clean up, are they?

Ian

[Hunter2]

20 thou is a lot to "skim" off a block. Just what brutal shape is the deck surface in???

I would first take all dirt, grease, oil off the block, pull the freeze plugs and bathe it in a 3/1 water/molasses bath to eat off the rust....get it out of coolant passageways etc. Agitate passageways as best you can. Remove and rinse with hose, examine and put back in the bath. Should be clean in 2-3 weeks.

Then run a steel straight edge over the block lengthwise and diagonally to see what gap you have...bet it is just a few thou. Anything less than 1.5 thou is OK.

My block cleaned up at the machine shop...but the head didn't....even after a second go in their bath. So it was into the water/molasses mix. In the photo, now ready for rebuild...hardened exhaust seats, new guides, new valves, new springs... A|fter rinsing off pieces that come out of the water/molasses there will be a very light flash of rust as it dries.

(molasses/water mix is biodegradeable, environmentally friendly...is really cheap and it works to get the rust off heads, blocks what have you...NOTE eats aluminum)