oil feed

[Guppy916]

Thanks Nick, no the cam journal by the dizzy drive has a crack the work shop said re mortgage the house to weld it, so looking for another block or engine,

Iv'e already purchased all the stuff for the rebuild thats why I was looking for a 2.5 block , is the 2.0 block recessed as well 

[Nick Jones]

The recess is not a 2.0 /vs 2.5 thing but an age thing.  Recesses adopted across the range sometime in 1972 I think.  Likewise there are subtle changes in the blocks over the years, but no specific differences between 2L and 2.5 that I'm aware of.  I've always considered them interchangeable.

The only practical difference between recessed and non-recessed is the head gasket.  While the recesses and thicker gasket fire-rings were supposedly added to reduce HGF between cylinders I've never had or seen a non-recessed one fail between cylinders on a Mk2 engine.  Mk1 engine yes, they have pathetic head studs and inadequate clamping force and also on the 4 cylinder engines where the cylinders are closer together.

Nick

[KevinR]

If you have a non recessed block, a good machine shop can add recesses. Likewise if you get a recessed block skimmed you should get the recesses cut back to the correct depth.

[Anglefire]

On 09/05/2018 at 9:43 PM, Guppy916 said:

Iv'e just been talking the the guy in the machine shop and he said first port of call is the PRV, he said the check the seat in the block,

I also spoke to Chris Witor and he agreed and told me to look at part number 132107 on his site,

He said "Granular debris may become embed into the PRV seat on the engine block preventing the valve from closing

use a shortened 9/16" drill bit as shown to clean the seat"

see photo, so when I get my block back this is my first job

How short does the drill bit need to be? I ask because despite changing my PRV and it being better for a few miles, its back to doing the same weirdness so next job is to clean the seat I guess. And how do you cut them down? (Perhaps a stupid question deserving a stupid answer!)

[Guppy916]

Just use your 4" grinder with a metal cutting disc . then regrind on your grinder, I've just done mine but mine is only 1/2"  may be 

2.5 blocks are different 

i'll check the length when I get into the garage  after breakfast, If the engine is in the car about 150mm long,

so long as you can get your hand on it to twist it