My '85 MGM, "Maisa"

[gadget73]

no bore work then?

honestly if you're having issues finding rings, measure the old ones if the holes didn't have to be bored. if the gap is still fine, stick them back in.

[Arquemann]

no bore work then?

honestly if you're having issues finding rings, measure the old ones if the holes didn't have to be bored. if the gap is still fine, stick them back in.

Orders were to check and deglaze the cylinders, they were supposed to call if there's a problem. So I guess the cylinders are round and straight enough. Goal was to rebuild with STD sized parts. I did not inquire any specifics when they called to say it's done. I'll want some sort of spec sheet, but I can very easily worry myself to sleepless nights over very minor variances. If the machinist says it's good, I'd be inclined to trust them.

I'll ask the machinist about piston rings when I'll pick up the block and crank. Mainly if there's any need to go with file fit rings.

I'm tempted to just get a good set of pregapped rings off RA, Mahle moly rings maybe? They're 50€ a set vs ~200€ for a set of file fit rings (plus a ring file). It's not really about the money, it's a shitton of tedious work to file rings to put them in a lazy, stock engine for street cruisin'. Obviously I want to do things correctly, but I think in this case the pregapped rings are right enough.

[Arquemann]

Heads are disassembled, gonna scrape the gasket remants off before putting them to soak in diesel. I dunno how I'm going to clean off the diesel off the surfaces I'll paint, but it'll be better than the caked on oil and grease that's currently covering alot of the heads.
Valve seals were pretty pliable still. Valve guides feel snug, the valves have some pitting, but nothing too serious looking. Should be fine to lap them by hand.

[gadget73]

clean them with whatever solvent, then take a propane torch to the block. That will cook out the solvent and give you a nice surface to paint. Don't need to put tons of heat in it, you'll see it darken as the solvent comes out of the pores, then lighten again when it cooks off.

[Arquemann]

clean them with whatever solvent, then take a propane torch to the block. That will cook out the solvent and give you a nice surface to paint. Don't need to put tons of heat in it, you'll see it darken as the solvent comes out of the pores, then lighten again when it cooks off.

Block got hot washed at the machine shop, I dunno how much prep it'll need before paint. Maybe clean off dirty fingerprints and remove moisture with a torch. The heads are my current cleaning dilemma, I could clean them with diesel and stuff, or I might just drop them at the machine shop to get hot washed aswell. I wouldn't have to clean all the diesel residue off and would get the cavities cleaner.

[gadget73]

if you're stripping the heads (you should) make sure you check the valve guide condition and I'd have the valve seats re-cut so they seal properly. Valves may also need a grind, but don't be surprised if the exhaust valves need replacing. Often the faces pit beyond what will clean up.

[Arquemann]

I cleaned up the valves in diesel and did a test lap (pun intended) on one of the exhaust valves. Yeah they're no good, a good cleaning and lapping showed how pitted they really were.
The intake valves are a bit pitted, but saveable. Though the seat has worn quite a groove into the valves, so the valve sit deeper. Considering stock intake valves are a whopping 2.65€ a piece and exhaust valves are 3.45€ off RA, I'll splurge a bit and order all 16 valves.
Surprisingly the valve seats are looking very nice, basically no pitting and a quick lapping showed a nice even finish, even with a pitted valve.
A valve job on canted V8 heads is so expensive that it'd make no sense to do on a set of shitty stock heads like these. Plus oversize valves and I'd be halfway towards new alu heads... Let alone rebuilt stock heads.

I previously mentioned that the guides are pretty good, they'll stay as is. New springs, valves and seals. I'll lap in the new valves when the time comes, other than that the heads are "done".
Tomorrow I'm getting the block and crank back from the machine shop, I'll leave the heads there for a wash.

[gadget73]

Most of the seat refreshes I've seen used what was basically a cone shaped stone chucked in a drill. If the seat isn't bad you give them a quick hit to smooth it out and call it good. Its not really a full re-cut with replacement seats and all that.

while you have it apart it wouldn't be a waste to do some gasket matching and cleanup work in the ports. Almost impossible to make it suck more than they already do. Assorted guides out there for where to spend your time with the grinder to get the most results but largely its cleaning up the lumps and rounding over sharp edges.

[Arquemann]

Got the block and crank back, looks pretty good, but the wash leaves a bit to be desired, innards are all clean, but some spots on the outside of the block are still dirty. But stuff is no longer dripping with oil, so it's atleast nicer to handle. They recommended against moly rings as the honing is a bit too coarse for them.
Picking up the heads on Friday, seeing how the block turned out after the wash, I won't be expecting miracles for the heads either.

Ordered a big bunch of stuff off RockAuto, gasket set, bearings, rings and stuff. Decided to split the splurging to atleast two batches, mainly to have shorter and more cohesive shopping lists and to have a better chance to remember everything. Might pay a bit more in shipping, but oh well.

Most of the seat refreshes I've seen used what was basically a cone shaped stone chucked in a drill. If the seat isn't bad you give them a quick hit to smooth it out and call it good. Its not really a full re-cut with replacement seats and all that.

while you have it apart it wouldn't be a waste to do some gasket matching and cleanup work in the ports. Almost impossible to make it suck more than they already do. Assorted guides out there for where to spend your time with the grinder to get the most results but largely its cleaning up the lumps and rounding over sharp edges.

Seats will smooth out fine with just lapping them, provided the new valves match the angle properly.

Would like to, but it's just not in the books this time.
I'd need a die grinder and the grinding bits, yeah they're not too expensive, but still a chunk of change I don't exactly have.
And mostly the fact that it's alot of tedious work, I'm admittedly a bit uncomfortable with air/power tools and coating every nearby surface in the garage in fine metal grit isn't exactly desirable.
Asked a friend a while ago if he'd give the heads a whirl, since he has experience. But he's got the same thing, he doesn't want to coat everything in his garage in metal dust.
I know there's easy hrsprs and terks to be gained, but I don't think it's worth currently.

[Arquemann]

Lovely, managed to get a couple tiny scratches in one of the fresh bores...
Tried out one of the old top piston rings in the bore, no matter how I cleaned the piston it still made a couple scratches as I used it to push down the rings.
Ring gap with the old ring is 0.04" top and bottom.

Fucking sucks but you live and you learn. Not gonna do anything about it.

[jaywish]

Ring compression tool?

[gadget73]

not gonna bother anything, 10 revolutions and most of that cross-hatch is going to be gone anyway.

[Arquemann]

Things have progressed slow, due to personal stuff, a random bout of depression and that I currently have 43,09€ to my name.

- Coolant and oil passages are cleaned, got a handful of rust out of the coolant passages
- New core plugs, block drain plugs, cam rear plug and oil galley plugs installed with some black RTV, didn't even line up the text in the core plugs...
- One of the block drains stripped out and ended up becoming an M10x1.25
- Ordered "5/8 bolts to plug the thermactor holes in the ends of the heads

Today I test fitted the compression rings to cylinders 1-4. End gaps so far have measured out between a snug 0.6mm and a tight 0.7mm. 0.0236 to 0.0276 in hamburgers. Better than I expected honestly, something to feel good about.
Waiting for my ring expander tool to show up so I can move onwards.

[DerekTheGreat]

....measured out between a snug 0.6mm and a tight 0.7mm. 0.0236 to 0.0276 in hamburgers...

Hamburgers.

What, you guys don't eat those in Finland?

[Arquemann]

Hamburgers.

What, you guys don't eat those in Finland?

Oh definitely not! We eat things called "porilainen".