The clearance looks good to me and unless you’re a ham-fisted gorilla, you’ll feel that. And when the bearing is fitted in the crankcase the ‘crush’ will reduce the clearance slightly. Use a smear of assembly lube on the bearings to help lubrication while oil pressure builds up.
Thank you @snotty and @77 Westy - that’s the reassurance I was hoping for. Had another bash and measuring the clearance using the dial gauge this time. Am getting consistently 0.06 to 0.08mm on No3 main and about the same if not a tiny bit less on N01 main. I think it’s time to stop worrying and move on! up… down…
It is . Had me guessing when I fitted new bearings on my spare engine. Bearings fitted dry, you can actually feel the slight clearance where the oil film normally goes. Give the journals a good splosh of oil, and it goes away
Quick question - with the bolt together cam and cam gears, should there be a star washer under the set screws? I think there should but can’t be sure! Cheers
Some progress - the short block is back together... Quick Question - with the new AA piston and barrel set do I need to gap the rings and scrub them all clean? Cheers
Oh, think I’ve answered my own question…. https://sites.google.com/site/stpsgarage/TechnicalArticles/preparingpistonsandcylindersforinstall
AA would probably tell you they are ready to fit, and they might be, but I would never fit anything without checking first. The pistons and cylinders are unlikely to be clean and the ring gaps may or may not be correct. And you'll need to weigh and balance the pistons of course. That article is quite good but simple piston ring pliers make removing and installing the rings a stress-free activity. And I’m much more sparing with lubricating the rings and cylinder bores – too much lube and the rings wont bed in. I use a spray of WD40 on the bores and just a few drops of engine oil on the rings.
Quite right and I glad I did; the were a couple of compression rings that were way under size. I’ve just finished putting the rings back on using the video’s method - if I’d seen your post I might have nipped out to Machine Mart but managed to get them all back without snapping any! The next hurdle is I’ve only got 0.5mm deck height…
Good question. If I put it all together with the bottom seal (0.25mm) and the head gasket (0.8mm) then returns a healthy 7.70:1. But I need some deck height - so; If I replace the bottom seal with a 1.00mm shim (giving 1.25mm deck height) and keep the head gasket at 0.8m then it drops to an asthmatic 7.12:1. However, if I then leave out the head gasket then it gives me 7.58:1. Given I started at 7.3:1, I'd be happy with that. I believe the received wisdom is to follow the VW Maintenance Bulletin (although I don't think it actually applies to CJ engines)to leave out the head gasket, so surely this all works? Any pitfalls? cheers...
I wouldn’t call 7.7:1 a healthy CR but it’s better than 7.12:1. Don’t use a head gasket, alter the deck height with cylinder base shims. If a 1mm shim and no head or paper gasket gives you a deck of 1.25mm and a CR of 7.58:1 that’s the best you can do. The heads don’t have a step, right?
