top end motor rebuild 94 350 tbi

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94z71yuk

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okay so i blew a head gasket so now is a good time to just rebuild the entire top end minus the rotating assembly. im not good at spelling and nor am i a master mechanic. i started this project with out thinking of taking pictures for other users but.
http://www.tahoeyukonforum.com/forum/attachment.php?attachmentid=16941&stc=1&d=1342375417

i will start now i started by removing the alternator then the ac bracket and idler and tensioner pulleys then the pewer stering pump which mine had me stumped. i can fit a 3/8 allem key so i figured it was held on by a bolt and my dumb self didnt refer to the hyanes manuel till i got frustrated. its pressed on for future refernce. another note is you do NOT haft to take the bolts out of the ac compressorjust take the whole bracket off much easier. :) after the power stering pump i removed the wather pump i just left the fan and pully all attached just to get it out of my way then i unpluged the harnes disconected the fuel lines and removed the throttle body.
http://www.tahoeyukonforum.com/forum/attachment.php?attachmentid=16942&stc=1&d=1342375417

after i removed the ignition coil and throttle cable bracket on the intake and thats where im currently at i'm removing the heades and having them resurfaced so any tips from someone who has done this or an experianced mechanic will be greatly appreciated.
http://www.tahoeyukonforum.com/forum/attachment.php?attachmentid=16943&stc=1&d=1342375417

okay so i went out and removed the dizzy. failery simple after you mark the dizzy and rotary button remove the hold down bolt (i just losened) just gently pull and wiggle till it comes up.
http://www.tahoeyukonforum.com/forum/attachment.php?attachmentid=16944&stc=1&d=1342375417

then i removed the intake. to remove i refered to my repair manual and it showed a diagram of which order to tighted the bolts back down and it said to remove reverse order. so i followed the instructions only turning the bolts 1/4 turn untill all pressure was off the intake manifold then i removed it. also sunlitcomet this is the picture of that block off plate i found could you explain to me what its for?

http://www.tahoeyukonforum.com/forum/attachment.php?attachmentid=16965&stc=1&d=1342376193
 

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94z71yuk

94z71yuk

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also what are those plates for on the very back water journals there was one covering each side and do i need them replace them or throw them away.
 

SunlitComet

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the idea is to not warp the manifold and ensure it stays perfectly flat. just use a straight edge and feeler gage set like the manual says to ensure it is all good. for the heads follow the order of tightening but back them off 1/4 turn at a time till unseated off the head to ensure an even removal. once again to just help that nothing gets warped or stressed in a concentrated spot. these water paltes you speak of get some pictures of original locations and post here. i am pretty sure all water passages are not used in the cylinder head but will need to see your manifold too to be sure. I don't have a pic of the 94 manifold on hand but the proper gasket set appears to block off the rears which is expected. post some pics and i will research it more for you. anything else you need?
 
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94z71yuk

94z71yuk

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Thank you sunlitcomet I assume that the passenger side is mirror the drivers side correct. So I have the heads removed I'm going to take them to the local machine shop to have them resurfaced and cleaned pressure tested and new valve seals put in. NOWi would really appreciate if someone could help me with cleaning. My motor has 244k on it and as you could imagine its very dirty. So what's the best way to clean the rocker arms push Rods intake and all that good stuff please and thank you :) Will up date with more pictures also how do I put pictures in the text. I want to edit my original posting and complete the write up with pictures and step by step so I can help future readers

---------- Post added at 01:45 PM ---------- Previous post was at 01:43 PM ----------

Not enough funds I'm in the process of a 383 stroker build with I hope to swap in early to mid next year with a carb I just need to get this truck running like a champ right now it's my dailer driver :)
 

SunlitComet

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use any cleaning solvent like b12. you can get in gallon cans at store. just make sure you blow out all passages in your valve parts. what else you want to clean?
 
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94z71yuk

94z71yuk

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okay so now i have removed the exhaust manifolds pretty simple just take them off disconnect from the y pipe first i had to put the bolts back in then take them back out lol.
http://www.tahoeyukonforum.com/forum/attachment.php?attachmentid=16966&stc=1&d=1342376526

so after you remove both exhaust manifolds i then proceded to remove valve covers and rocker arms. valve covers were easy four bolts then you were done. now the rocker arms since my truck is 4wd and pretty high i sat on the radiator support and loosened all the rocker arm nuts fist then i removed one by one being sure not to mix them up. my reapir manuel said to put them back where you got them from so i placed them on a clean surface lined up to keep them orginized.
http://www.tahoeyukonforum.com/forum/attachment.php?attachmentid=16968&stc=1&d=1342376526
okay so now i was ready to remove the heads and thanx to sunlitcomet for the heads up. no pun intended. i removed the heads by the instructions sunlitcomet gave my and i did so in the order that my repair manuel told me i assumed that the passenger side is morror the drivers tho my book never told. so now i got the heads off and need to clean the motor. on question i have is i believe my motor has been messed with before im unsure but i dont believe it has stock pistons here is a pic.
http://www.tahoeyukonforum.com/forum/attachment.php?attachmentid=16969&stc=1&d=1342376526
okay now i need to remove the gasket material clean the intake, tb, rocker arms, push rods, and the vally under the intake and between the heads. and thank you sunlitcommet for reccomending the b12 ill check that when i go to the parts store. but one more question. what is the best way to remove the gasket material from the block and intake with out screwing it up. any good tips would be appreciated.
 

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94z71yuk

94z71yuk

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BTW thank you sunlitcomet for being so helpful. i really appreciate this.
 

SunlitComet

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i would not suggest using it on the block if it is still assembled.

---------- Post added at 01:44 PM ---------- Previous post was at 01:37 PM ----------

clean as much as possible by hand. you do not want the junk or solvents in your bearings even tho there is a oil filter installed. if you get it in the pan drain it with oil put cheap house brand oil and a high flow filter in it. get the priming tool with a power drill and use that to circulate the oil a while to help clean things out. drain it again and use a high filtration rate filter and do it again this time while turning crank a few turns to get everything good and lubed. when all done use some good oil with detergents to finish it off over time.

btw those are stock pistons.
 

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