Ruck

Swapped this seized engine out for the other block in the garage; when I pulled the intake manifold I think that's where the leakage was happening. On the re-assemble (not really a rebuild) I RTV'd the manifold, put everything together, and after a really disappointing start (lots of white smoke) I just let the thing rev because it wasn't running poorly, figured it was just in the exhaust. Sure enough, after about a half hour the thing cleared up, no white smoke. Sadly, I gun the engine and get a lot of blue smoke with the exhaust. When I peered into the cylinders, the walls were not scored, nor were they crosshatched, so I suspect I have worn rings. Next step is to follow the instructions in these links, see if I can isolate the problem: http://datsun1200.com/modules/mediawiki/index.php?title=Compression_Test http://datsun1200.com/modules/mediawiki/index.php?title=Smoke I'm also going to replace the valve seals since I have a few sets of these from previous projects. Any feedback or suggestions appreciated.

And this link: http://datsun1200.com/modules/mediawiki/index.php?title=Smoke

I was searching and found this link, answering my own question. Apparently no difference between a wet and dry compression test will point upwards to the valves. http://datsun1200.com/modules/mediawiki/index.php?title=Compression_Test

Appreciated. I'm now driving this thing back and forth to Starbucks. It blows blue smoke on acceleration. I'm going to do a compression test. Any way to diagnose bad valve seals (versus worn rings)? Valve seals are relatively easy to replace and I guess I could just replace them and see whether that makes a difference.

I just finished a engine block swap the other day and didn't prime the pump with oil. Seized it up in about four minutes.

Thanks. For an older engine (250K+ miles) I should assume the wear needs to be measured. Can this be done without removing the pistons? How about the crank?

My sweet '83 King Cab needs an engine and although I could find a used one (been there, done that, sad story) I am seriously considering a rebuild of one of the spares I have in the garage. I want the equivalent of a factory rebuild that will last at least 50-75K miles. Is there already something in this forum I've missed titled 'Top ten things for a moderately mechanically inclined person to consider before rebuilding your engine'?

I've replaced my fuel pump twice in two years, so I wouldn't rule out a bad fuel pump even if relatively new. Is it possible for it to pump but not pump with sufficient pressure?

Awsome answers, which I wish I saw before I went out and bought another engine. Sad story: Got me another engine, swapped it out, and along the way rebuilt the oil pump. Spoiler alert: oil pumps must be primed with oil to work. Three minutes into warmup the engine seized solid. Probably the original issue was not torquing down the intake manifold. I have another block, now I'm thinking of a complete engine rebuild...

Bought an '83 KC 4x4 for $384 at a yard sale a few years ago, swapped in my '84 Z24 engine with a quarter million miles on it and ran it for a few years. Last summer I got the ol' white smoke out of the tailpipe, so I did a new head gasket. Cranked it up, and it ran fine (though a little skippy) for about a minute, then I started getting white smoke, serious white smoke, like the neighbors were gonna call the fire department volumes. A few tries, the engine is skipping pretty regularly. A friend with some mechanical expertise suggested it may be fixed, there just may be a lot of moisture in the catalytic converter and I should try to run it out. I suspect it is not so simple. Here's the deal: I have another engine sitting on an engine stand in the garage that I can rebuild with a $400 kit, then swap in; I can buy another beater engine for $200, or I can ask my new friends on this forum what the heck I should do. The vehicle is a honey, no body rust, no damage, shitty interior but I don't care; I love that it purrs when it is running and it's dirt simple to repair, normally. The junk is piling up in the side yard, need to get this thing running so I can hoe things out...