'88 G63B oil consumption issue/general engine questions

hello all, first time poster, long time lurker. I've been going through the forum getting info from all the good threads on here.
to explain what's going on with my engine is that it smokes and burns quite a bit of oil while being run. i've noticed it smokes heavily on start up, lessens and almost disappears when idling while warm but smokes while driving or under any kind of load. this leads me to believe the valve seals are bad. i've taken the head off the engine to access the valves safely and to generally inspect the head/pistons/block. everything looks ok to me (except the heavy carbon build up). i have new gaskets and a timing belt to put on but i'm curious if i can reuse the head bolts? I've seen the torque spec listed on here as 65-72 ft/lbs and with visual inspection none of the bolts seem streched or damaged. Another question i have is, is there anything that can be done to clean out lifters? or is it better to replace them? before taking the head off i would get lifter tick on a cold start.
TLDR: can head bolts be reused? can you clean out lifters or it better to replace them? I'm interested in reusing the parts i have (within reason)

Some bolts can be reused. Some can’t. I always suggest going to ARP head studs since they are 1000% better. The only downside is you might not to remove some material from the underside of the valve cover. It’s nothing major. It just takes a little time. As for the hydraulic lash adjusters. They are cheep and replacing them is standard. Same with the thermostat. It’s cheep insurance.

thanks for your reply, i'm guessing head studs simplify disassembly? or are they also much stronger?
I'm going to go ahead and order those lash adjusters , and i'm definitely going to swap out the old thermostat.
i'm trying to get the truck back on the road without spending too much on it since i didn't pay to much for it, although i do recognize that's kind of an oxymoron when talking about a truck from the 80's with 175k on the clock lol

Head studs simplify reassembly, ensuring proper alignment of the head and gasket to the block, and improve fastener strength/reliability, as the studs only undergo a stretching force when the nuts are torqued to spec, whereas head bolts undergo both stretching and twisting forces that can contribute to distortion/damage of the fastener and threads.

hello again, things have been going well as far as repairs go but i have run into a problem, i found the ported vacuum switch under the intake manifold is missing a couple of the plastic nipples. i understand the emissions stuff is superfluous when running a weber carb, but i currently have the original mikuni carb which is working. i'm not having much luck finding a replacement and im curious as to what can be done and how important the valve is overall. from what i have read it shuts off the emissions stuff such as the EGR valve and the like while the engine is cold.

Not clear what "ported vacuum switch" you're asking about; could you provide a photo?

BTW, also saw your "shoutbox" question about the threading there -- threaded insertions that need to be air/liquid tight use BSPT (British Standard Pipe Tapered, aka ISO-7), usually 1/8"-28 TPI, rather than the N.American NPT (e.g. 1/8"-27 TPI), but BSPT-NPT adapters are available.

if you're on a budget, I'd leave out the ARP studs. oem head bolts reused on turbo 2.0 and 2.6, no issues
dowels on block deck will align head & gasket fine
someone weber converting, probably have the parts you're missing.... just have to figure out what bits

sorry about that, i try not to spam. this part is labeled as a thermo valve in the vacuum diagrams and web searches call it a ported vacuum switch
i took to the parts store and it seems to be a 3/8s pipe thread fitting which you were right about. here's the picture of the part
https://imgur.com/a/sK8OrhO

Quote:

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Originally Posted by dash

if you're on a budget, I'd leave out the ARP studs. oem head bolts reused on turbo 2.0 and 2.6, no issues
dowels on block deck will align head & gasket fine
someone weber converting, probably have the parts you're missing.... just have to figure out what bits

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yes i think i'll have to save up for those upgrades , but they're good suggestions and eventually i will have to make the switch over to the Weber since parts seem to be hard to find , especially when it comes to the stock carb and it's associated parts

Quote:

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Originally Posted by Mitsuzero

sorry about that, i try not to spam. this part is labeled as a thermo valve in the vacuum diagrams and web searches call it a ported vacuum switch
i took to the parts store and it seems to be a 3/8s pipe thread fitting which you were right about. here's the picture of the part
https://imgur.com/a/sK8OrhO

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Search for P/N MD101597. A wrecking yard may be the best place to find one. Both the G63B and G54B (87-89) used the same four-port valve. Here's an earlier thread that discusses the valve and might be of help:
http://www.mightyram50.net/vbulletin...name-this-part

That thermovalve isn't open to the intake manifold; it just blocks/opens (at a certain coolant temp) passage of vacuum between the two vac hoses normally attached to it. With the stock Mikuni carb, I'm not sure how well it'd run without the thermovalve operational, or whether that'd do better with those two hoses bridged together (or replaced with a single continuous hose) vs. blocked/capped off at their source.

A Weber swap wouldn't use the thermovalve at all, so you'd only keep it in place to cap the coolant port it screws into, or you might find a BSPT 3/8"-19 TPI threaded plug for that. When removing the Mikuni, you'd remove the carb along with all vac hoses attached to it and the control box bolted to the driver-side inner fender. Then with the Weber you'd really only need two vac connections: the fat one from the manifold to the brake booster, and a smaller one from the carb or manifold to the distributor vac advance capsule.

The two-port thermo-valve activates the Auxiliary Accelerator Pump when the engine is cold (less than 120*F). This supposedly improves drivability, but I haven't noticed any adverse effect after capping the manifold and carb ports long ago. With the Mikuni, the four-port thermo-valve regulates vacuum supplied to the choke breaker and opener, canister purge valve, and the EGR valve. With a Weber the valves are just plugs in the manifold holes. Post #2 of this thread has pics of both the two and four port valves:
http://www.mightyram50.net/vbulletin...257-EGR-system

Yes, I'm hoping to find a 4 valve thermo valve, I've found a few that look like they'll fit, if not I might have to try and attach ports to the old valve or see if I can get it to run decently without it, if not I'll have to buy a Weber kit down the road

I was able to find a thermo valve made for Nissans with the same thread count and size, only thing is it's got 3 ports instead of 4, i figure i can use a tee to get vacuum to the 4th line.

Quote:

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Originally Posted by Mitsuzero

I was able to find a thermo valve made for Nissans with the same thread count and size, only thing is it's got 3 ports instead of 4, i figure i can use a tee to get vacuum to the 4th line.

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Here's an illustration of the thermo-valves that includes the switch point temps of each nipple. Might help you decide how to adapt the Nissan valve.

http://www.mightyram50.net/vbulletin...id=27865&stc=1

Thank you, that's an excellent diagram. I guess I'll just have to call Standard and figure out what ports do what or how they open. I think I'll combine the choke and fast idle vacuum lines together since they kind of go hand in hand