ok heres whats happened with the truck. its a 2000 v6 4x4 blazer 153k, my wife was driving it it started to get hot and the heater quit working. it was dumping all the coolant into the oil instantly and started to foul/kill the cyls one by one.
it blew the head/intake gaskets and warped the pass side head 2 years ago. i pulled the engine and tossed it, so i wouldnt have to deal with a refurb of the block/heads just to fix a problem caused by the gaskets.

i grabbed a nice running salvage engine with 115k and a parts warranty from olsten auto salvage, i watched it start and run before it was pulled and paid for. the engine sat for 14 months in storage, dry of fluids and i got it swapped in a few months ago.

i got it running and it ran fine, i started it every other day for 2 weeks and let it get to temp, but it still sat because my oil filter lines had bad seals. i replaced the oil line seals when they came in and drove it around the block a few times, it ran fine.
the next day it only had good oil pressure while starting, pressure dropped to nothing while running. there was rust colored water in the exhaust system and it mixed coolant/oil and started smoking a light white smoke. i shut if off and drained the oil/coolant right away.

i assume its because i forgot to do head/intake gaskets when i put the motor in after it sat for so long with dry gaskets.





i started the topend rebuild process last week, i left the engine in the truck as i didnt want to fight the bellhousing bolts or wrestle the oil pan past the front axle.
i tore it down to the block, leaving the entire block intact.
the intake/head gaskets were most likely the culprit they were in rough shape and i believe i saw a coolant leak on the pass side head or intake gasket on the rear inward portion of the head/intake.

the intake mani/injector heads were nasty with carbon buildup, the heads werent too bad. i cleaned everything up and surfaced the heads with very fine emerycloth/micro alumn wool to remove the stuck on gasket material. they look fantastic, no warping, no gouges, no blown passages, all the valves seat properly.

the block looks good, just dirty with mixed oil. the bores/hones look great, no scrapes or oil marks. ive wiped down the cyl walls and piston tops with ATF to protect them/loosen deposits. pistons/rings look good, no piston slap or side to side wiggle. the camshaft/pushrods are in good condition, no burned up/scarred lobes.





i have the felpro premium gasket kit/head bolts for the topend rebuild.
ive also deleted the in-radiator coolers and gone to standalone aluminum units for the engine/trans oils, to take strain off the cooling system as i tow atvs with a small trailer often.

bear with me this is my first time doing internal work on a pushrod v6. i know dohc 4cyls and single/dual cyl 2strokes pretty well and have done rebuilds on them before so im not new to engines.



whats the best way to flush all the deposits and mixed fluid out of the bottom end and oiling system, without harming the bearings in the block or the oil pick up/transfer system? i dont want to loose pressure again.

how should i go about priming the engine with oil?
should i prime or lube the bottom end before i install the topend after or both?

should i use copper gasket spray on the headgaskets before i install them?

is there anything i should look for or im missing?

do the 4.3 have any specific things that need done to them while rebuilding?

any and all info is greatly appreciated! thanks in advance guys!