INTERNAL ENGINE MODIFICATIONS Valvetrain |Heads | Strokers | Design | Assembly

HELP PLEASE!! Engine Vibration after rebuild LQ4

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Old Aug 14, 2010 | 08:28 AM
  #21  
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Originally Posted by Remember_54
After ALL test done we found out that we do not have compression on right Head, driver side compression is good, but other side compression is zero..

So what that mean, is that mean I need to change Engine Cylinder Head Block because it seems to have damaged?

visually they all been ok.. before installation I even installs new valve ans spring plus rockers
Y'all didn't forget anything in the intake ports? Like a rag r something!
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Old Aug 14, 2010 | 08:42 AM
  #22  
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Good compression is around 180psi, anything below 130 means something is wrong.

Thats really odd for an entire bank to not have compression....all the valves were installed, right?
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Old Aug 14, 2010 | 02:07 PM
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probably valves was not installed propelly, that what i recived from Paul from perfomance shop:It could be that the valve seats were cut deeper on that head or perhaps the head or block were milled more. Loosen the rocker arm bolts just one or two turns and crank the engine over without starting while checking compression. Your hydraulic valve lifters may not have the correct pre-load. This may be causing the problem you are having. If that is the problem you may be able to correct it by placing a small shim washer under the rocker support tray (0.030" thick). Another test would be to remove the rocker arms and pressurize the cylinders one at a time, or use a leak down tester. If the valves seal you will know that the lifters were not adjusted properly. If the lifter adjustment is the problem you can use rocker shims or a slightly shorter pushrod


actually there are zero compression in all celinders from that head block
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Old Aug 14, 2010 | 03:52 PM
  #24  
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Man thats wild to have nothing! valves would have to hanging open for some reason r not opening at all!
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Old Aug 14, 2010 | 10:56 PM
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guys how i can know what is a right way to plug coils packs, i mean the a lot of wires and i we not sure which is going in right way, maybe to get some books for this engine, where it will show how factory right it should be pluged, how to make this right ?
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Old Aug 15, 2010 | 01:05 PM
  #26  
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one more question, for a moment in another cylinder head i have 150psi, as per previous suggestions from guys good compression should be 180psi, so what you think, is that better to reinstall the valves and adjust, i know the problems with them, so is it better to open that head again, or it can stay 150psi? after all this spending money and put so much in this engine i want everything to be best, so is this better to reopen that head? i already open onother one for adjustment, please guys suggest thanks a lot to all of you, for time which spending to answer me
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Old Aug 15, 2010 | 01:10 PM
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to adjust the rockers, you just need to pull the valve covers; no reason to take of the head.
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Old Aug 15, 2010 | 11:26 PM
  #28  
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yes we did it first time, on another block which had zero compression, by playing with bolts compression changed little, so we decide to take out and make it propelly, so now i`m thinking to open another one which has 150PSI, do I really need to do it? how you think.. or 150psi is good enough?

guys how i can know what is a right way to plug coils packs, i mean the a lot of wires and i we not sure which is going in right way, maybe to get some books for this engine, where it will show how factory right it should be plugged, how to make this right ?
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Old Aug 15, 2010 | 11:54 PM
  #29  
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A crude way to check if the coil packs are on is start the engine cold, and place your hand on the primaries of each exhaust. The cylinders that are firing the primaries will get too hot to the touch, the ones that aren't will feel warm, even hot eventually but you'll still be able to touch them. That or buy a manual that can help you out more. But the engine harness should have the wire clips at various lengths that will kinda of make it obvious which wire clip goes into which coil pack, and each coil pack should be located right above the spark plug that it goes too.
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Old Aug 16, 2010 | 12:02 AM
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Originally Posted by Spoolin
A crude way to check if the coil packs are on is start the engine cold, and place your hand on the primaries of each exhaust. The cylinders that are firing the primaries will get too hot to the touch, the ones that aren't will feel warm, even hot eventually but you'll still be able to touch them. That or buy a manual that can help you out more. But the engine harness should have the wire clips at various lengths that will kinda of make it obvious which wire clip goes into which coil pack, and each coil pack should be located right above the spark plug that it goes too.
thanks a lot for your help.. actually I want to get book where it showing how they should be connected.. but still can not find it, i get book Service Manual for this engine there is no any info in there..

I need something look like wiring diagram for coil packs do you have link from where I can buy it?
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