Things to do before installing 4.3l in 97 blazer

[jmcleek]

Just what do I need to replace on a 97 vortec that I got used before putting it in my blazzer besides the parts they broke takeing it out ,or what is deffernt?

[BarryB]

I always like replacing the rear main seal, and what ever gaskets that are hard to get to once its in the truck.

[95 S_Trucker]

I would recommend the oil pan gasket, rear main seal, a new timing cover(plastic), and lower intake gaskets. You will be doing intake gaskets sooner or later, might as well do them now while its easier. Make sure to get the updated gaskets

[jmcleek]

I have herd that the v8 vortecs had problems with the intake gasket so I was wandering about the 6s.
parts destroid ,distributor cap and modual oil sender and what ever that other sensor is by that.

[lowrollin70gmc]

I would take a good look at the new used motor and see if there is evidence of a leak. I don't like pulling anything apart that doesn't show signs of leakage. Often times a new gasket can also leak and no need to fix what's broken. With that said, the oil pan and rear main are done in minutes with the engine already out.

The 4.3s have a reputation for consuming intake gaskets so it's worth while to replace them. I like to use the upgraded Fel-Pro gasket set, as it includes steel based gaskets as well as valve cover gaskets, throttle body, etc.

I recently swapped engines in my 97 and both motors had new intake gaskets, but I had parts in hand so I installed the nice FelPros. I was going to do the rear main because it's so easy but it had a fresh one installed when I pulled the flexplate. I kept the stock senders as they aren't too bad to install in the truck, and a new distributor cap/rotor and wires never hurts.

[jmcleek]

The "new engin came from a 2 wheel drive and is going in a 4 wheel drive will I need to change oil pans and the thing the oil cooling lines come off of?

[95 S_Trucker]

You will need to swap the oil cooler outlet at the block. The 2wd had the filter going straight down. The 4wd has the filter behind the bumper. If you don't switch it, the oil filter will hit the front diff.

I' showing 2 different part numbers for the oil pan. I didn't think there was a difference. But if you are replacing the gasket anyway, its no big deal to swap oil pans. If you do swap pans, make sure the oil pick up is at the same place.

[jmcleek]

So what is the best way to clean out the oil lines, thought about useing an old fuel pump and some desel fuel to clean the lines.

[jmcleek]

I have every thing under the hood in front of engine removed exhaust manafods removed and the converter bolts removed . what is the easyest way to get to the bell housing bolts and the bolts on the back of the heads?

[hotstuff]

long extension and universal from underneath

[jmcleek]

Will try. Being a 4 wheel drive, can"t drop the back of the trans/transfer case but a few inches- tail hits on tortion bar cross member.

[jmcleek]

Engine / tran. is out. To get to the bell houseing bolts first needed to drop the transfer case ,then the transmission and cut all the electrical ties the last mechanic used to tie every thing up. to get to the last plugs and ground s on the back of the engine. This thing was leaking like the Exon Valdez, is there a good degreaser that will not mess with the electrical connectors?

[68C15]

Originally Posted by jmcleek

So what is the best way to clean out the oil lines, thought about useing an old fuel pump and some desel fuel to clean the lines.

NO!!!!!!!!!!!!!!!!!!!!
replace with new ones from the dealer. Do NOT use dorman hoses. repeat, DO NOT USE DORMAN HOSES!!!

Originally Posted by jmcleek

I have every thing under the hood in front of engine removed exhaust manafods removed and the converter bolts removed . what is the easyest way to get to the bell housing bolts and the bolts on the back of the heads?

I bend the pinch weld flange up and use a swivel socket on a loooong extension. It helps also if you have a truck driver's dictionary. The ground wires, fuel line bracket etc. on back of heads you pretty much need gear wrenches. In non-rust belt areas I've heard of guys removing body mount bolts and jacking it up to get at bell housing bolts.

as for the oil pans; 2wd and 4x4 take different pans and pick-up tubes. Make absolutely sure the back of pan is flush even with back of block.

that thing you called the module inside the distributor is actually the camshaft position sensor.

Check to make sure the plastic distributor housing didn't get damaged.

after all said and done, you'll need a scan tool to make sure cam retard (dist. position) is correct. The spec is 0 +/- 2 degrees but I find they run better with -5 to -8 degrees depending on chain condition.

[jmcleek]

Have full gasket set+ timeing cover will check timeing gears have both oil cooler hose sets , trans/transfer case gasket ,trans filter ket ang have new oil pump on order. 2 wheel drive and 4 wheel drive oil pump are the same , oil pans are dif. New hy vol oil pump instructions say to check clearance. Anyone have experience with this? 4x4 pan is a little deeper.

[68C15]

you need the 4x4 pick-up tube since the pan is deeper and has a different shaped sump. I'd pass on the HV pump. It will wear out the distributor drive gear. Those gears aren't cheap and it doesn't need high volume

[jmcleek]

How much play /defllection is passable in the timeing chain?

[68C15]

Ideally, none. With free play comes unstable idle and if it gets severe you will have lean codes and CMP and/or CKP sensor codes

[jmcleek]

Hmmm play is about 1/2 inch or so. got a new set on order.

[jmcleek]

the play was about half on the new timing set. need to swap out harmonic ballancer , outer weight slips on enter rubber. timing cover on ,rear main seal changed..

[68C15]

word of further advice. Put antisieze on threads and shank of exhaust manifold bolts. If you ever need to remove them, you'll thank me.

[jmcleek]

Pulled the ballancer from the other engine and I think it will be ok sence the timing marks line up with the engine set a tdc. their is a little grove on the sealing surface. though. valve cover of and cleaned ,intake off and apart. first plastic distributer that I have seen.. I like to use antiseze copper on them ,and teflon on all bolt that go into the water jaket.

[68C15]

blue loctite on lower intake bolts and torque to 132 "lbs. Any more and it will distort the block
doing intake on an 02 Astro right now (ugh, I hate vans) and on Tuesday I do another on an 02 S10. I think I could do these blindfolded

[jmcleek]

Oil pan on, oil cooler adapter on, lower intake on. working on valve covers descovered hole in 1 of them, cleaning cover from dud engine to replace it.

[jmcleek]

Used a pair of Papermate pens in oppossite corners to giude the intake on . Just the right size to fit in the bolt holes in the heads and the manifold hole still fit over. Second valve cover on. stopped for the day. as hard as the little screws that hold the cam senser in to the distributor are to get to + out I 'm thinking of using a new one instead of the one I pulled from the old engine.

[68C15]

turn dist. shaft and the screws are wide open.
personally I'd leave it alone. They rarely give any problem. The only time I've seen a code set for CMP is when the chain is severley worn and the CKP-CMP relationship is off