'80 99 With T16V - Sven Block!

[swmeatball]

I got the timing chain cover mod half done, cut out the bits and had my buddy weld it up, he commented on how nice the casting is compared to most automotive stuff, no voids or impurities. Its at the machine shop right now, should be done this week and hopefully I'll get the bottom end buttoned up shortly.

Picked it up from the shop, looks pretty good, said he took about .015 off and it didn't quite clean up, people typically put a little RTV or something on there to help it seal?

[swmeatball]

Now that the timing cover is done I'm working on adapting the manifold to fit the fuel injector block, the plan is to plug the bolt holes, weld the plugs in, then drill for the new ones. It looks like the bolt holes on the underside of the manifold will either end up a s slots or I'll add some material so there is enough meat to drill, how have others done it? The area above the top holes will need to be clearance'd a bit to allow the fuel rail to bolt down. I also have to fill the injector bosses in the 2.1 manifold, thinking about a longer plug that is roughly profiled to match the inside of the runner, weld it in from the top and finish with the die grinder when I'm gasket matching.

I spent some time staring at the head / fuel injector block / manifold and there do not appear to be any oil or coolant passages that communicate from the head, which I wasn't sure was the case, so that's a relief.

Any advice on silicone or something to seal the head gasket where it hits the new part of the timing cover?

Clearance at top boss

Gasket on timing cover

[DrewP]

Some silicone or Loctite 518 should be fine, looking good!

[Geoff]

Loctite 518 is supposed to seal gaps up to 0.010". If he took 0.015" off the Loctite 518 might not be appropriate and you may want to use a grey silicone (so you don't have ugly blue stuff seeping out).

[swmeatball]

Do I need to do any sort of special prep to clean up the mating surface on my engine block? I'm using the new style head gasket to match the T7 head (obviously), one of the layered steel dealies (MLS right?) At one point someone advised me to sand it with some paper wrapped around a milling parallel, sounds about right, but now I'm reading that the gaskets have some special requirements regarding surface finish? I didn't have the shop deck it or anything.

[Jordan]

I think the important part is flatness and cleanliness. MLS gaskets deal better with disimilar metal expansion/contraction, but are also more sensitive to surface prep as they have less "crush"

[squaab99t]

Do I need to do any sort of special prep to clean up the mating surface on my engine block? I'm using the new style head gasket to match the T7 head (obviously), one of the layered steel dealies (MLS right?) At one point someone advised me to sand it with some paper wrapped around a milling parallel, sounds about right, but now I'm reading that the gaskets have some special requirements regarding surface finish? I didn't have the shop deck it or anything.

My machine shop asks what kind of gasket I will be using, MLS or conventional? The MLS requires a finer surface roughness on the head and block.
MLS are pretty common for modern engines or you can check with the Cometic site. They make aftermarket head gaskets in MLS and should have the machine surface roughness spec.

[swmeatball]

I went over the block with some 220 grit wrapped around a milling parallel, its got a pretty good surface finish, significantly better than 32, I'm trying to avoid having it decked because I don't want to increase the compression any more than I already am with my small squish area pistons. I found some pitting right where the gasket seals around the bore, its not terrible but it lightly grabs a fingernail:

Guess I should just man up and have the thing decked? How much should be taken off? I know this will affect my timing as well. I've heard that some have filled pits in with jb weld, I'm confident enough in the finish and general condition of the deck that I'd go this route if it's an acceptable fix.

EDIT:
Well seems like it is an acceptable fix, but machine shop says $35 to deck it, just gonna go that route, should be done anyway really. Hopefully they won't have to take too much off, I'm going to figure out my C/R too, while I'm there I'll get my pistons and head cc'd.

[swmeatball]

Finally some progress, got the bottom end mostly buttoned up, pistons / crank etc. are in, both aluminum covers are on, chain / sprocket and guides in, water pump on, still have to do the oil pump. Got the wrong pickup at the junkyard, the wire is coming off in the wrong direction to clear the mounting bolts, once that is corrected I'm going to spin the flywheel back and forth a little to make sure I'm getting the ignition signal into the megasquirt.

Most everything is glued on with Loctite 518, kinda magical stuff, packaging claims it'll do .050" by the way, I'm using it on all the paper gaskets and as a gasket itself on the coolant jacket drain housing, seems like that should be fine.

The plan was to have it all done by ski season, looking like mid January at this rate, missed on worthwhile powder day already, dammit.

[Geoff]

Loctite 518 is great. I've been using it at work on NPT pneumatic fittings. It makes it so I can thread parts together and align them where I want instead of having to jam the threads hard and keep turning as hard as I can to get it aligned. Real handy for things like gauges that you want to point in a specific direction. Once hardened it cleans off super easily too using the Permatex gasket remover (spray), which I think is probably relabeled oven cleaner.

[swmeatball]

Oven cleaner is definitely my other magic stuff, does an amazing cleaning of carbon that just will not come off.

Getting the head back together, I read on this page http://www.serioussaab.co.uk/procs_page ... _head.html that when rebuilding heads he laps valves until "...seal on both valve and seat with no pits evident on either surface." I lapped mine but the valves still show some pitting, if I go for a second round it seems like there wont be any coating left on the valves, on the other hand tempted to just go for it...

I lightly sanded with some 220 wet/dry wrapped around a milling parallel, the surface finish is good, was pondering getting it decked but its in pretty good shape, a very light ring around one cylinder but the rest is flawless.

[swmeatball]

Got the valves back in, solvent takes a few minutes to seep through, instead of instantly before the lapping job, so I'm declaring victory. Also managed to remove an exhaust manifold stud without much fuss, seems like drilling all the way through is helpful.

I didn't do any more lapping, the valves don't look great, but my plan was to do as little to the head as possible. I'm replacing a few dead lifters with ones from other heads I have lying around, I think 6 total had very little action left, even after a kerosene bath. At some point I would like to build one up for real, but don't think I'll ever want to spend the crazy money for new valves, are there any alternatives?

[swmeatball]

So I've a dumb question, the pistons sit a hair above the face of the block at TDC, I did have the thing decked to clean it up, its somewhere in the .002-.005" range, hoping thats ok? Seems like the new (MLS / T7) gasket is around .020-.030 thick so I'm assuming its all fine provided the gasket doesn't crush a bunch.

[swmeatball]

Got the engine on the transmission, psychologically important milestone for sure, I'll get the head on next - going to go with the cams from one of my T5 heads and keep an eye out for an intake cam from the n/a 9000 94-98, nothing at the junkyard currently.

[Geoff]

So I've a dumb question, the pistons sit a hair above the face of the block at TDC, I did have the thing decked to clean it up, its somewhere in the .002-.005" range, hoping thats ok? Seems like the new (MLS / T7) gasket is around .020-.030 thick so I'm assuming its all fine provided the gasket doesn't crush a bunch.

That should be fine. That is sometimes done on purpose to increase CR.