86 K10 5.3 swap

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Camar068

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10 yrs Air Force
the lever was there as well whatever the part below is. Is the part below the delay circuit? Noob question, haven't made time to look at it really lol.

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Honky Kong jr

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the lever was there as well whatever the part below is. Is the part below the delay circuit? Noob question, haven't made time to look at it really lol.

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I do believe that is what you need, that heat sink leads me to that conclusion
 

Camar068

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Thanks
 

Camar068

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well got the gaskets changed. Learned 2 lessons.

-on LS engines, don't forget to put the lifter guides in place BEFORE you install the heads ($65 for new bolts)
-if you get out of sequence when tightening TTY bolts, don't back any of them out. I did that on #5 on the passenger side. It is now 110° passed all the others. I did check torque on it.....it has more than those with the standard 22 ft#'s then 90° and another 90°. Even better would have been to get bolts that I could re-use.

Another lesson learned as well. Pay close attention to wire colors when doing your own harness.

The front O2 sensors are identified by either a purple wire (bank2) or a purple/white wire (bank1). Your engine will run like **** with them plugged into the wrong bank. I blame the engineers for this one....I mean really.....make it super obvious.....make one yellow FFS.

My scan tool led me to figure that one out. The Short Term Fuel Trim (STFT) and Long Term Fuel Trim (LTFT) readings were -20 on bank 1 and +25 on bank 2. They are normally pretty close to zero compared to those numbers. I was close to getting O2 sensors after seeing the numbers. I troubleshot else where until it hit me that the numbers I was seeing were almost perfectly opposite of each other compared to where they need to be. We'll find out tomorrow lol.

I'll be addressing the harness issue tomorrow. Kind of a good thing it happened cuz the trans harness was touching the exhaust so I need to check for crispies and fix as needed.

Feels good to be going in a positive direction now compared to the past 2 weeks.
 
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Camar068

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forgot to mention I was getting random misfire code P0300 and p0172 bank 1 running rich.

video below is where I paid attention to the STFT and LTFT.....@ around the 6 minute mark.

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Camar068

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still running lean on bank one but not missing. Gonna let it cool off and check for COLD vacuum leaks and then look at the O2 sensors.

Runs night n day with the O2 sensors wired up correctly lol.
 

Honky Kong jr

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still running lean on bank one but not missing. Gonna let it cool off and check for COLD vacuum leaks and then look at the O2 sensors.

Runs night n day with the O2 sensors wired up correctly lol.
You do realize if the ECM is telling you it’s lean it’s actually running rich. It says lean because that’s what it’s doing to try and make it run right leaning it out. It will reach a point it can do no more and throw a code. A to rich condition is inversely the same type of thing.
 

Camar068

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On the first run I calculated 18 MPG's over a 200 mile street/interstate run.

I checked the speedometer because I couldn't believe it. The gauge says 35 and gps says 38, and 80 mph is dead on.

The 2nd 200 mile run gave me 15 MPG's but I have got into the throttle a little more and went through some good mountains today.

I need to get a flame arrestor and a flip-over valve on the vent still. With the vent lines behind the tail light (high), I'd hate to get hit there and need a parachute lol.
 

Camar068

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She's still running fine. I lifted the hood to show someone and noticed the sight glass (plastic tube) on the fleabay can looked orange/yellowish. Drained it today and found this. The passenger side cover doesn't have one....but will be getting one soon after seeing this.

There was only about half a cup that came out, but it didn't show up in the sight glass until it got colder outside. Engine oil looks fine.

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LateOnTheBrakes

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Any issues with the stock LM7 pan clearing the supports when you install the engine mounts?
 

LateOnTheBrakes

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Cool. They made it sound like I would have to notch the crossmember for the pan to fit. What is the pedal you ended up using? I took the pedal from my 2005 Suburban donor vehicle but there is no way it is going to fit under the dash. Even with a bracket to locate it further left I do not think it will clear the bottom of the dash.
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eskimomann209

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On the first run I calculated 18 MPG's over a 200 mile street/interstate run.

I checked the speedometer because I couldn't believe it. The gauge says 35 and gps says 38, and 80 mph is dead on.

The 2nd 200 mile run gave me 15 MPG's but I have got into the throttle a little more and went through some good mountains today.

I need to get a flame arrestor and a flip-over valve on the vent still. With the vent lines behind the tail light (high), I'd hate to get hit there and need a parachute lol.
They say the speedo is always a little off. Factored in to keep people from speeding.
 

eskimomann209

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Cool. They made it sound like I would have to notch the crossmember for the pan to fit. What is the pedal you ended up using? I took the pedal from my 2005 Suburban donor vehicle but there is no way it is going to fit under the dash. Even with a bracket to locate it further left I do not think it will clear the bottom of the dash.
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Some people get away with using the 6.5 gmt400 pedals. I think it might be in this thread.
my trucks pretty low and I don’t have clearance issues. With the ground or any crossmembers.
 

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