So question since my motor is flex fuel vin Z how do I go about looking for a rebuilt or used motor what do I need to look for? like what years can I use for it I know that the heads have to be 706 heads as far as I knw. I found out the heads are bad there valves that aren't seated and a lifters have some scaring on it... Its got 207,000 so there's no point in rebuilding the top end without doing the bottom.. I need a motor but don't want to screw myself on getting the wrong one..
Acts like it wants to run but doesn't.
- Thread starter NO4NSHIT
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- 2003 yukon help newbie
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How did you verify valves not seated? Compression numbers decent. Did you remove heads? Many here don't do bottom end until 300-400K . There are a few threads of replacement engines. You can go gas only with different inj harness. Pics please.
Try car-part.com
Try car-part.com
Need something a lil cheaper was thinking about a used motor but can't find any vin Z motors and was curious as to what I would have to do to put a non flex fuel engine in..?? I can find non-FF but not finding the Flex fuel that my Yukon came with.. not sure what years I can look for or anything
Again Try this
There were some as low as $1000 low miles. in Fl.
There were some as low as $1000 low miles. in Fl.
corvette744
2004 Z-71
I see that a lifter is chewed a little but i wasnt expecting the motor to be torn down lol.I still dont think you have your problem fixed unless it was a intake gasket leak and when you install the new gasket its sealed properly.Their is no way to tell if those valves are leaking your compression test was good.If you would of took the core out of the compression line and injected air in the cylinder when you brought each one to tdc and heard air coming in.From either throttle body- oil breather- or exhaust pipe then i would of comdenmed them.My god you have a ton of work to do now and i hope you dont have the same codes when its all back together-that would ****.I think your lean condition would of been from fuel pump or major intake leak with fuel trims that high not valves.Hope im wrong good luck i give you an A for effort.
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My question is that I was told I can only use the L59 motor 2002-2007? I just want to know what years I can look for that motor in? And if I can use a LM7 motor and if so what would I have to change in order to do that? Or is it not worth it to change it all to use the LM7 motor and I just need to look for a L59 motor?
