birkhoff

What was the most you ground off a bucket? Also curious to know how the surface finish worked out.

Well, dimensionally the same, but valve stems are routinely modified (up to a point) while buckets are not normally ground in an overhaul. The concern with both is how deep the hardening extends into the part and maintaining the required finish and shape There should be no back and forth tipping valves. Once the required cut is calculated, it would take a pretty bad machinist to not hit the spec on reassembly. I can't recall 100%, but I think my shop budgeted about 4 hours labour to assemble both heads after cleaning and recutting/boring the cam journals, so that means time for assembly, measure, take apart, cut the valves, have a smoke break, re-assemble, and check. There's $400 CDN mind you, right there! Swapping buckets and/or grinding them is the only option with the head on the block, but if it is already off and you have access to vernier equipped grinding machine. . .

I believe machine shops just tip off the top of the valve stems to set clearance, even in a rebuild situation. In a rebuild, the valves will sit deeper in the head anyway, so clearances will all be too low. It is a simple matter then to set up, measure and record what has to come off, disassemble, then tip all the valves at once to the required cut. No messing with the buckets in that case.

Start cap on the motor. Can you actually mill the hardened face of a cam bucket? I would think this is a grind only proposition.

Excellent progress! Looks like the next step is to install cam seals and gears. Friendly heads-up at this point. It is easy to mess up the dowel pin alignment on the avcs gears -- I almost got bit, but got lucky. There is a mark on the cam gear that shows the position of the hole for the dowel pin. That helps align things from the outside if you side mark the angle of the dowel on the block. You may also want to make a trial fit of the gear without the seal in place and note how far back it goes when it engages properly. You have to use the cam bolt to draw the gear in the last little bit, but the body of the gear is unhardened steel and the pin is hard -- if you draw it in even slightly out of alignment there will be trouble. Try to get it part way in by hand. Worst case scenario means you will need a new avcs gear, which is $$ and will cause a delay in progress. Once the gears are on and torqued the belt install should go smoothly.

My bad. You guys are absolutely correct. Firing order is indeed 1-3-2-4 but #1 and #2 are at TDC at the same time, whilst 3 and 4 are at BDC as the pictures clearly show. Thanks BMB and Stkmlts for this. I know you have been thinking a lot about this point, and you got it right the first time! The thing that is not obvious from looking only at the crank is that rods in paired journals are pointing in different directions once in the block. Eg, #2 and #3 which are paired on the crank, lead to cylinders on different sides of the engine!

Huh? Now I'm confused. If you exchange #2 and #4 in your description, then I'm back to my happy place. Look at a picture of the subi crankshaft. #1 and #4 are grouped together, as are #2 and #3, 180 degrees offset from the first pair. So if #1 is at TDC then so is #4 and #2 and #3 are at BDC. Firing order is therefore 1-3-4-2 with 180 degrees of crankshaft angle between each ignition event. Theoretically it could also be 1-2-4-3 but there are probably some harmonic reasons that is not desirable.

Don't bust yourself up over the timeline. You have more ahead of you than behind, but you are making amazing progress! The trick (as I think you have found) is to work systematically and with concentration. Having to back up and redo things is a schedule killer. I call dibs on the princess chair. Looks like a perfect place to take a break and regroup when something seem not quite right and needs thinking through!

If I recall there is a bit of leeway in positioning the water pump on the block (in contrast to the oil pump, which is dowel pinned). By a little judicious adjustment before snugging the water pump down, you can get both seals to contact. I don't anticipate this will be a problem for you. You could always put a daub of black RTV along the gap in order to ensure a dust-tight seal for the timing gear. Or not.

Nice job on a quick recovery there. Sometimes getting the dang project moving trumps perfection. Can't you compare the dish on the pistons you still have at the bench? You have the forked `B' grade as a standard and at least one other of the used ones. And as fahr-side suggested, check piston weight. You can also do that with the spares. New stock is within a gram or two out of the box, around 415g for the set I worked with. I'd weigh them first. It'd be astounding if they had the same weight but different crowns.

Not sure what I am seeing there. The ring compressor should sit straight on the piston, with the leaves all aligned and only the piston skirt showing before you start. It should be quite firmly cinched down. Once you start feeding in the piston, the compressor must stay in contact with the firedeck at all times, otherwise a ring will slip out. Maybe you are just experimenting there to show us that the oil pack has made it in, but otherwise, that picture looks pretty scary!

Bummer. That's the only thing I can think of at the moment. Very bad luck. Hold on there. Not quite true. If you build the motor up and it is compromised by that cylinder, you lose all your prep steps, the bearings, pistons, a good bit of the head work, and a full gasket set. You have a lot of reasons to... Take a deep breath and get back on track. I suggest at this point that you split the block, order a new piston (A grade this time) and take it, the other pistons and both halves into a reliable machine shop. Have them hone out the scored bore to fit the new piston, and then hit all the other bores with a light hone. The bottle brush hone is already a weak point in your program and it will cost you nothing to have this done once they set up. While you are waiting to for the machine shop to do its thing, show us a picture of your ring compressor. This should not happen. Something is not right with the compressor or the setup.

AND, dots on first and second ring all pointing up (I see one of them there). Getting them in the bores is easier than you might think. Lube well with plain engine oil and go slowly just in case a ring hangs up. Very unlikely, given the large chamfer on the bores, but if it does, reset the compressor and try again. You can tap them in or simply push with your thumbs.

I see. It is the top (compression) ring you want to be careful with. You have extra gap there which is the right way to go if you deviate from the spec window. I set my gaps as top= 0.0110, second= 0.0170, control=0.0170. So my top was also a little open compared to spec, but for my purposes, reliability trumps performance. So far nothing blowed up Not sure what the STI limit spec refers to, but at nearly 4 times the upper limit of stock gap, it seems to give a lot of leeway for an 'oops' when you hand file your rings.

Assembly lube. Just spread out a medium-thin layer with your finger over the whole bearing surface. It will squeeze out when you torque the case. The key thing is to keep it off the block mating surfaces. Any stray lube will be washed out by the oil on startup. Maybe I missed it, but when did you size your rings and load the pistons? What gaps did you decide on?

For the record (which is approaching mini-opus status ), what are you painting with? Primer? Topcoat?

Make sure you protect the bores immediately after washing and drying. They will flash rust before your eyes once you remove all traces of oil. Probably you know all this already, but as it is your first rebuild . Wash the bores and every open galley using a brush where you can, and lots of detergent and water. Any good dishwashing liquid will do, although Dawn-brand is traditional. Scrub, brush, rinse and then do it again. And again. Especially the bores, to the point that a clean white cloth shows absolutely no sign of dirt when you use it to dry off the bore. Blow out with compressed air, dry the bores with a (new) clean cloth or paper wipes, and then wipe down with oil of your choice. Nothing kills a new rebuild like leftover abrasive from a hone, bottlebrush or otherwise. I just use motor oil on the bores. Some prefer transmission fluid. Not sure it really matters but make sure you get every spot or you will have rust in a matter of hours if not minutes. Especially if you are working in a humid environment. I wouldn't reuse the half moons, in case you are taking a poll. Painting before or after washing? No experience here. Sent from China.

A good machine shop would probably weld that up and recut it. Not really a homebrew option. Since none of the gouges connect inner to outer directly, I would take a bet on letting the sealant handle it. Not sure that you would gain much from JB weld. Question about the cut you took. Maybe it is just a shadow, but it looks like the mating surface on the case just outboard of that bolt hole in the last pic did not get cut. Is that because it is lower than the rest of the case (that would be a surprise) or was your surface plate not wide enough? Put it another way: are you still flat to spec on the mating surface, all the way across?

To go half way between STD and first undersized. Best to put them all on the same side. Off centre? Yes by some fraction of the oil film thickness!

You use two sets. One STD and one undersize by 0.025mm. They are available. That translates to a 4 tenths thicker shell for each bearing half. When you need to tighten up clearance in one or more bores, you use one STD and one undersize shell. Or both undersize if it is really bad. I had to do that on one journal. However, if the OP can get a consistent measurement of 12 -15 say, by plastigage and interpolation, it is probably not worth the hassle. A little more clearance didn't hurt me. Without the half shell swap, I would have been in the 20's on the worst journal and that just seemed too much.

Side clearance is not particularly tight on these engines. I'd be surprised if it wasn't within spec as is. Should be checked though. You will also want to check crank end play since that is a wear area. Target spec is quite wide (12-45 tenths). Mine was ok out of the box. I AM surprised you are getting such uniform measurements on oil clearance with plastigage. I had nothing as good as this on my build. After polishing, my main journals ran from 2.3616 to 2.3620, so a variation of 4 tenths already, before accounting for oval in the bores. How many times did you measure? Did you try the crank in different positions? If it is repeatable, I'd just go with it. Clearance (calculated) on my mains ended up at 12, 13, 14, 16, 14 (#1-5) in tenths. That was with swapped half shells. I have no problem with hot idle oil pressure even though all but one of these are over spec. And, I used the original 10mm pump, from the donor block. OTOH, if these numbers are correct, an undersize half shell in every journal would pull you down 4 tenths in each position, if you do want to run stock clearance.

What is this A/C thing y'all are talking about? They say we might hit 24 degrees today. Finally, summer heat has arrived!

Cylinders have thin iron sleeves pressed in or cast in place (not sure which). Once you clean the firedecks, you should be able to see them. Not sure if the top of the sleeve has a lip or not. If yes, that would make a larger iron sealing surface. If I had to guess, I'd say not. Sleeves seem to index to a step in the bottom of the bore.

Additional 2+ hours. Better you than me! OP is stubborn, but because of this, we all benefit -- it can be done! Great job. They look perfect.

Rod bolts, yes, so you don't scratch the crankpins when you drop the piston/rod package down the bore. As MAX diplomatically points out, truly new ideas in this business are few and far between! Rod socks, not so much. I made up a set of these thinking along the same lines as OP. Abandoned them after a few tries when they kept slipping off. Maybe they could have been modified, but I found the rods didn't mark up the bores anyway. Yes, they're gong to clunk around as you roll the block back and forth on final assembly. I just didn't find it worth the trouble and seemed a pretty good way to introduce contamination at the final assembly stage. Fitting the mains you don't have the rods on anyway. That's where all the time goes in. Question. You are going to continue sanding the heads. What about the block? Are there not similar issues on the fire deck? There is always the option to pack up all 4 pieces, grab the pistons, and drop them at any decent machine shop. 1 day later, perhaps $150 poorer, you would have the heads and block decked and the bores cleaned up with a professional plateau hone. A person would have to be a real ba$tard to suggest you didn't build it from scratch just because you used a machine shop that has the necessary (expensive) equipment to do that part of the job properly and efficiently. Just saying. . . .