I found a video online of a guy starting an LS on a stand using an un-modified factory harness and a co-worker just happened to buy a 5.3 this past Sunday and plans to use FiTech. I offered 150.00 for the harness and ECM and he gave me the airbox and MAF in the deal so I have some spare parts.
He was not sure it was a 5.3 like he was told so I used the bench harness I made a year ago and scanned the ECM, the bad news is he was sold a 4.8 and I am pretty sure the seller knew it.
However, I picked up the harness on Thursday and my coworker could not get the clip off the TB so he yanked it off, I was able to repair one wire and re-pin the rest and then found it has different injector plugs. Not a problem because the adapters are cheap from Amazon.
But I did find some motivation after getting the spare harness and worked on the engine. I installed the rear seal, flywheel and pulled the exhaust manifolds back off the heads. Found good quality M8x1.5 bolts (didn't buy enough), a drill powered pump to prime the oil pump but didn't find the metric fittings to hook up the pump and temporary oil pressure gauge, Amazon to the rescue!
I started cleaning up the head and remembered I had two broken exhaust bolts. This turned out to be butt-pinching ordeal that took a few hours and multiple trips to Home Depot to repair. I first tried to weld a nut to the broken bolt that was flush to the head. That didn't work and I air quenched it and believe that caused it to harden. I could not center punch the bolt with a mini-sledge.
So I went to HD and bought Colbalt bits and an ez-out. The first bit, I believe 1/8" would not even mark the bolt. So I searched online and found on Practical Machinist that heating the bolt would soften it so I grabbed the propane torch and tried for a half hour and broke the 1/8" bit. Went back to HD for another 1/8" bit and it would not mark the bolt after heating again with the propane torch.
So then I fired up the O/A and heated it up again, I was really concerned about damaging the aluminum but either I get the damn bolt out or I have to pull the head and take it too a machine shop. I heated the piss out of the bolt and grabbed the next size bit and the largest recommended for the ez-out. And it started cutting, it cut good with a long stream of steel but it cut slow. And the ez-out would not grab so I started drilling with the 1/8" bit to deepen the hole until "crack", I broke the second bit as it reached the end of the bolt.
Fortunately the ez-out grabbed but I was sure it was going to break, so I heated the aluminum with the propane torch and the bolt finally moved and eventually I removed the bolt. I believe this took about three hours and about a half hour for the other bolt that was not hardened by welding heat.
I spent a little more time gasket matching the exhaust ports that may be a waste of time and may not even be recommended but there was a good 1/8-3/16" of metal that needed to go.
I have some bits and pieces ordered from Amazon and on the way and need to pick up some more bolts on Tuesday. I did find Ace Bolt and that place turned out to be a garage mechanics "gold mine", so much that I can use in one location.
Today I am pulling the Blazer tank from the Cherokee so see what I need to use it for the test run. I used nylon hose and quick connects to connect steel lines to the fuel pump module but I need to do something similar to connect it to the LS.
I would like to run it long enough to log data on HPT so I am working on the cooling. I have read not to run the water pump without water and guess what, I chunked the Yukon radiator and evaporator after tripping over for a year
Maybe I can make the Cherokee radiator work.
My goal is to determine if my "re-flash" is successful. It it is, if the engine won't start using my modified harness that will point to my harness as being the problem.
I will also order the transmission parts this weekend and hope to finish at least the guts next weekend even if the pump and valve body take additional time.
And last, I was originally going to buy LS3 exhaust flanges to mate up to the LS3 manifolds but someone on LS1Tech suggested welding v-bands to the manifolds. I changed my mind again and want to buy the flanges and use the factory gaskets, they are expensive but tested and work so that is on my list for the upcoming week.