Still trying to understand what may have gone on inside the timing cover. The large countersunk flat screws in the plate are almost loose. They looked like they may have been staked at some point but no longer are and appear to have been removed at some point. That probably wouldn't have helped with the oil leak either. Also from what I can see behind the plate the gasket doesn't look "right". I guess the plate (which I need to Helicoil a few holes at the least) needs to come off for a proper fix, new gasket etc. From the manuals it seems the camshaft needs to come out along with the crank gear. This means the lifters need to come out. I've pulled the distributor/fuel pump/lifters cover and now wondering how far I go before putting the lid back on the can of worms? The Lifter Cover looked like it was never off before (needs a new gasket now). The Camshaft gear looks like it may have had a puller on the center shaft area at some point. Would someone have removed the cam gear without removing it/lifters fron the engine? So to get the lifters/cam out, how far do I need to go up top to get the push rods out of the way? Just remove the rocker assembly to pull the push rods? Or should I stop, button everything up and forget trying to put that plate gasket on. I know the leak situation will be improved but not completely eliminated.
Toughest part of this job might be getting the old, baked-on gasket material from the lifter cover off the block.
I love the 3M Roloc discs - used a lot of green (grinder and plastic) ones on body work. Only thing here is I don't like the idea of blowing that stuff all over the engine with everything together. I'm trying to cover everything up as much as possible to keep the lifter areas clean, etc.
Just ordered a cheap razor scraper on Amazon - the one I have is junk.
Also ordered an SK "Hand Tool 6652 Offset scraper". Never had any luck with the plastic razor blades. There's a nice set of carbide scrapers but I started wondering why scrape the block with something harder than the casting - even tool steel is hard enough scratch/cut? Found an old wood-handled stiff putty knife that is soft enough to file a 90 degree flat cutting edge on, it seems to work great. May need to keep sharpening it but soft enough to hopefully not muck the block up too much. Seems like the solvent gasket removers get mixed reviews?
In the process of pulling the lifters, this one came out in 2 pieces with what must have been a developing crack and now looks like a perfectly new break? Don't see any scoring to speak of on the block bore but will look closer.
Can I just check/measure the cam and buy a single lifter (comparing diameter measurements to the old one) from Toyota, or do I need to buy all 12 new lifters and worry about break-in, how the cam will react to that upgrade, etc. etc.? Are there other issues I should look at? Backlash on the timing gear seems to be at .0035". Did I save anything down the road by finding this, I assume a 2 piece lifter bouncing around would not be good at any engine RPM?