Need help with doing a rebuild 1994 Silverado 1500 350

Discussion in 'Chevy Truck Forum' started by KnockinTurtle, May 17, 2017.

  1. KnockinTurtle

    KnockinTurtle Member

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    Hello and great to join new forum,

    I need some advice on what to do, I took my truck to shop for misfire/running rough/rich and had some test done and turns out I have Burnt valves and poor compression on 2 cylinders .

    They want 1500$ plus tax to repair but I feel I can fix her! just need some advice on what I should buy parts wise .


    My compression results are
    #2 = 135
    #3 = 75
    #1 = 149
    #8 = 148
    #4 = 150
    #5 = 85
    #6 = 145
    #7 = 140

    I dont have a huge budget so looking at the best option for I wont have to sell a kidney.

    Shop notes : Burnt Valves's, 2 cylinders poor compression, fuel kicking back up the intake causing knock noise on acceleration, rough idle.

    Any advice from you pro's would be much appreciated, Thanks in advance.
     
  2. mowfixer

    mowfixer Full Member

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    looks like head gasket is blowm between cyls 3 and 5 since they both have low readings.

    I had the exact symptoms and when I removed the head the gasket was missing between the low reading cylinders. You didnt say how many miles are on the engine but mine was about 112K when it blew. Not a terrible job to remove the heads and take them to a shop to be rfeworked. You need a couple special tools. One to remove pully from power steering pump and if I remember some torx bolts on one of the brackets.

    My heads checked out fine by the machine shop and I didnt even have to do a valve job as my budget was low. I did put new valve stem seals in and that stoped a smoke cloud when I first started. The old ones had dry rotted and were completely gone.

    Now if motor has lots of miles the bottom end might be in need of some work too.
     
  3. KnockinTurtle

    KnockinTurtle Member

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    Thanks for the quick reply, The truck has 177k miles.
    I was looking at some head gasket engine kits on ebay,
    I seen people online grind the old valves they take out, is it better to replace the valves, I see the vavle set goes for about 80$ on ebay.

    I dont have ways of removing the engine out of the truck so I am trying to do all i can while keeping the engine in the truck.
     
  4. mowfixer

    mowfixer Full Member

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    I did the head job in the truck.

    If your wanting to change valves you will need to have a valve job and most likely seats recut. With 177K valve guides may need work as well. A machine shop can do that work properly and also check head surface for being true and not warped.

    Dont go with cheap head gaskets. I used felpro and they are high quality and will last the rest of the life of that motor.

    The fact that you have compressions of 140 might show some bottom end wear.
     
  5. KnockinTurtle

    KnockinTurtle Member

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    #5 KnockinTurtle, May 17, 2017
    Last edited: May 17, 2017
    ~~~~~ Parts List~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~`
    Felpro Head kit

    Head bolt kit

    Valve & Spring Kit

    Thermostat

    PCV Valve

    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    I plan on taking heads to a machine shop to renew and valve job, surface flatness.

    What are you thinking would possibly need replacing in the lower end? Can it be done in the truck?

    I assume more info will be found once i take apart the engine as to what all should be replaced.
     
  6. dirtrider73068

    dirtrider73068 Senior Moderator
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    Best route to take is remove the heads take them to a machine shop and should be about 200 a head maybe even less to valve work, new valves, new seats, a head gasket set shoudl be about 40 bucks and put it back together. Those prices are just a guess way back when I had head work done on a engine. Call around to machine shops see what they charge and what they do on head work, tell them you may have burnt valves and want them fixed. I bet its going to be way less then 1500. Also get a haynes repair book for that truck it shows how to remove and install the heads, and also shows how to tighten them down and gives the torque specs for the bolts as well.
     
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  7. KnockinTurtle

    KnockinTurtle Member

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    I edited the parts list im making in the post above, does that look right to you?

    I will call around on some head rework prices, I appreciate the help. I plan on ordering all the parts I need once I can verify that is all that I will need.

    Thank you
     
  8. dirtrider73068

    dirtrider73068 Senior Moderator
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    Honestly me personally would not do the head work myself, from what I learned back in school its alot of work to cut the valve seat, or trying the get the valve seat out and new one in, and lap them unless have a machine to do it, shouldn't need new bolts or at least I never bought new bolts. Just need a good head gasket set, have the head work done at a machine shop and put all back together.
     
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  9. gmctrucks

    gmctrucks Full Member

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    I wouldn't buy the gaskets off of eBay not unless there a good brand and buy NEW head bolts it could be that you blew the gaskets due to stretched head bolts ARP is a good brand you can reuse them that's how good they are while your there replace the timing chain and both gears again buy good ones.

    Maybe new water pump if you have the extra coins.
    Good luck! GMC


    If you with a carburetor go with Vortec heads more Zoom Zoom
     
  10. mowfixer

    mowfixer Full Member

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    Yes replace the water pump if its not already been done. When you see all the work it takes to get it exposed you dont want to have to do it all again a month later.

    The most difficult part of the entire job was getting the exhaust manifold bolts loose. I suggest you ger some PBBlaster and start soaking them every day. I soaked mine for a week and still one broke off and I had to drill it out and extract the broken bolt.
     

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