So....its been leakin out the optimal side, slow yet steady. Ordered the gaskets and the MPFI upgrade....they come in today and a frost plug let go too. So, can"t delay any longer. Wish me luck, that a large job.its a 4.3L but the manifold gasket leakage and replacement is about the same on the 5.3 and 5.7. Mainly work with simple hand tools and also a genuine pain. But, happily all the connectors because that the electronics are different and also its around impossible to confused them and also get them in the wrong spot.So...to the job.Here....the frost plug top top the rear vehicle drivers side started weeping today.
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And here on the passenger front of the motor, the entry manifold gasket has crumbled (they space plastic and also 100% fail between around 100K and 150K miles....mine has 149K). Fortunatly, both leaks space to the outside and not into the oil pan. So, no washed the end bearings. The intake gaskets fail to the inside about as often as not, usually destroying bearings before you find out ya got a leak.

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First, I gotten rid of the air crate system and then the throttle body. I"ll it is in doing the throttle body mode (remove the blockage at around 10 oclock on the accelerator plate that reduces low and midrange torque because GM surveys established that folks didn"t want numerous power turn off the line). Clean that up, reduced off the offending blockage and also reassemble because that reinstall tomorrow.
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Once the plastic plenum is removed, I note the original CSFI (Poppet Valve) central fuel injection. Been acquiring the occasional slow start. This will acquire replaced through the more reliable MPFI electronic fuel injection which is a standard GM upgrade since there were so countless complaints around the unshrouded poppeds gunking up and also sticking, etc. CSFI to be last provided on the Blazers in 2002. This one has 149K on the so, might too replace it through the better/newer mechanism now. Amazon to the rescue, $160 saved and also arrived in 2 days.
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To acquire the reduced manifold off, remove whatever on top. Traction the wiring up and also out of the way, loosen the bolt stop the fuel pipes and pull the assembly up the end of the method (no must crack the brief lines native the bracket...just blead the down before pulling out the pipes). Remove the coil. Eliminate the PCV, breather pipes, water neck, heater hoses, EGR, etc. Ns pulled the alternator for more room and likewise removed the ac compressor (just put it out of the way, don"t open up the pipes), take it off pan belt, water pump bypass hose, brake vacuum hose, distributor cap and wires.Finally, remove around 3 bolts and also 3 nuts native the AC/Steering Pump bracket and also slide it forward 2" to uncover the one concealed intake manifold bolt on the DS prior of the manifold.
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Turn the engine by hand come TDC top top the compression stroke. Rotor should allude at the triangle top top the dizzy base....marked in white. There is no time adjustment, so the dizzy has to go earlier in precisely on this marks or it won"t run appropriate or in ~ all. As soon as the dizy is out, execute not turn the engine or the oil pump drive shaft, so the later, you can ago the rotor (counter clockwise) approximately line increase the marks on the reduced shaft and drop it right earlier in the hole. When the marks line up prefer shown, you"ll understand its in right and will start and also run.
Pull the eight bolts the secure the reduced manifold to the heads. Yank the manifold and you get to check out the crumbling and broken plastic GM gaskets. Also with the radiator/block drained, you"ll obtain some coolant in the valley, that"ll have to be mopped out and also with every the work, an oil and filter change, immediately, is indicated.
Cleaned up and the new Fel agree perminant gaskets sitting in location on the heads. Threaded holes were swarfed out v solvent and a an excellent set that gunbrushes. You can tap lock too but will need a long expansion for the tap....brush is simpler if they space not too cruddy. RTV is used on the front and also rear in the valley. And also a bit more sopping up coolant come do. Final assembly will certainly be tomorrow. For now, cleaning all the threads on bolts therefore they deserve to be sealed and also properly torqued. If in over there I replaced the valve cover gaskets. The plenum and fuel rails will acquire all new Fel pro gaskets too, they space in the kit. $20 saved on Amazon because that the Fel Pro best kit and also again, here in 2 days. They all arrived as I to be finishing cleaning up the manifolds!
And here, the old layout poppet injectors removed and replaced by the Multiport Injector. Monitor the directions together #3 needs to go behind and also over #1 in order because that the tubes to fit the plenum without interference.
Tomorrow is reassembly and also I have to fix the frost plug. Climate a 24 hour sit because that the RTV come cure and also with luck, Monday morning is Fire Up.
Started in ~ 0700 this morning, worked till 1530 consisting of cleaning up the tools and garage. Got it all back together and also battery back in, no smoke. Did not begin it yet. The brand on the fel agree RTV because that the front and rear the the manifold states 15 minute to skin, 5 hours to dry, 24 hrs to cure. So, can"t put the coolant earlier in till about 0800 Monday. For now, I"ve triple checked it all and have no left end parts and all the connections are made, hoses and electrical. Likewise tightened up the 2 weeping frost plugs....hopefully they will certainly seal otherwise I"ll need to dismount the motor.Removed the gaskets first thing this morning and also dry to the right the manifold three times to ensure I can hit the overview studs I placed in and also had every the cables and hoses routed the end of the means so the manifold would drop down right onto the gaskets and also rtv at the ends through no smear. Wound up finding the the best position was belly throughout radiator, feet top top garage door.....so, gaskets on and guide studs in place and also rtv ~ above the ends....
Slipped the manifold right right into place without any slippage that can have knocked the end the rtv ~ above the ends. ~ sealing the manifold bolts with white pipeline thread sealer, I placed some in finger tight and also pulled the guide studs and also started torqueing the manifold bolts. Three torques, 50, 100 and also 144 in lbs in the appropriate cross sequences and also did a final examine to ensure every were in ~ 144 in lbs....just for peace of mind.
Stabbed the dizzy, no dice, a tooth off....pulled aligned the reduced dimple through the line and also stabbed again 17eleven much more times, no dice, would certainly not seat except when turn off mark. Finally got a long screwdriver down in there, rotated the oil pump shaft a scooch clockwise, realigned the dizzy and dropped that in and finally, seated on mark. I"m hopeing I obtained it right. If not it"ll either not begin or run unstable as a cob....but I have actually high hopes.....I think its right. Heres a photo of it seated however off mark....one tooth off and 30 minute to gain it to pick up the right gear tooth and bottom out.

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Here most of the manifold fittings and also electrics and modified throttle body is ago in place. Ns worked back to prior in order to ensure i didn"t cover up something that necessary hooked up!
Everything earlier in, bolted/torqued/snugged/lubed/sealed, etc. Looks right. 50twenty twin checks together I went and upon finishing up. Addressed a broken windshield washer line....no an ext drip there either. Coolant in the radiator tomorrow morning and also I"ll revolve the key. At least here, with the battery hooked earlier up, I"m not seeing any kind of smoke!
Drivers side behind frost plug that was leaking. The push in plug was replaced with an expandable plug and I put my wrench on the nut,,,,,finger tight. So, snugged it up and also the weep stopped. So, we"ll see. With luck, and also even though this one can be obtained to without increasing the motor, I"d rather try snugging it up for now than replacement. It was only put in this summer once the engine mounts to be replaced. Finger crossed. Close investigate reveled an additional expansion plug on the Passenger prior under the engine mount....and I uncovered a autumn of coolant on the motor mount....so......sliding mine 3/16" thick open wrench right into the 5/16" open slot in between the engine mount and the block, I uncover the seed on the expansion plug.....spend several minutes figuring the end upsidedown-rightietighty-leftyloosie and sure enough, the was only finger tight. Provided it a an excellent snugging up. They leak now, the goin come a shop to have actually the engine lifted out!
I think the hard component now is waitin it rotates the rtv cures so, I"ll most likely settle ago with a couple aspirin because that the aches and pains and a great bourbon and also a movie till its time to walk to the garage again.