Pros/Cons: Installing Harness before Engine - The 1947 - Present Chevrolet & GMC Truck Message Board Network

cebra · 01-10-2019, 12:21 PM

I am debating whether I want to hook up my harness (standalone harness from BP Automotive) to the sensors on the motor before dropping it in or after? My thought is after to keep from accidentally routing the harness some place I can't get it out if needed or pinching it when dropping the motor in...as I look at it, it may be tough to route once the motor is in due to the number of wires running near the bottom of the motor. Thanks for advice.

Macdaddy1 · 01-10-2019, 01:55 PM

I installed mine after I dropped in the motor and then played with wire routing. However, my cab was off at the painters so it was easy on just a frame.

**1971Stepside** · 01-10-2019, 03:42 PM

I put my BP Automotive on after the engine was in. Cab is on, but no fenders. I have plenty of room to work the harness where I want it. It will come off and go back on at least two more times before I am done.

**mongocanfly** · 01-10-2019, 04:16 PM

I would wait til after install...the only plug that's hard to get to is above the starter....leave the starter off til you get it plugged and the rest is easy....no sense fighting the harness while your installing the engine

cebra · 01-10-2019, 05:42 PM

Quote:

Originally Posted by mongocanfly

I would wait til after install...the only plug that's hard to get to is above the starter....leave the starter off til you get it plugged and the rest is easy....no sense fighting the harness while your installing the engine

Interesting, I would have never thought to leave the starter off for install as pulling one off a Silverado at the JY was a pain. Are they not as difficult to install on the C10 as they are to get off the Silverado? I have to drop my motor in with all sheet metal installed (doing it at night on the roof of my parking garage). Can you get that plug on after the starter is installed?

cebra · 01-10-2019, 05:44 PM

Sounds like after is the consensus.

**1971Stepside** · 01-10-2019, 05:46 PM

I put mine on with starter in place, but I had the header removed. With the starter and manifold in place it would be tough to do

sprint_9 · 01-10-2019, 07:12 PM

Keep in mind you can only pass the harness one way through the hole if you use the grommet provided with the bp harness and its 2 1/4 hole or what ever it is.

For example, putting the harness on the engine and then dropping it in the frame and stuffing the ecm side of the harness into the cab wont work, the hole is too small for the plugs to fit. You can get 1 or 2 plugs in, but not all.

If not using the grommet and passing though the hole then it would be no issue either way.

**nsb29** · 01-10-2019, 08:55 PM

Quote:

Originally Posted by sprint_9

Keep in mind you can only pass the harness one way through the hole if you use the grommet provided with the bp harness and its 2 1/4 hole or what ever it is.

For example, putting the harness on the engine and then dropping it in the frame and stuffing the ecm side of the harness into the cab wont work, the hole is too small for the plugs to fit. You can get 1 or 2 plugs in, but not all.

If not using the grommet and passing though the hole then it would be no issue either way.

That’s only if your ECM is going to be in the cab

sprint_9 · 01-11-2019, 12:29 PM

Quote:

Originally Posted by sprint_9

if not using the grommet and passing though the hole then it would be no issue either way.

Quote:

Originally Posted by nsb29

that’s only if your ecm is going to be in the cab

fyi

01-10-2019, 12:21 PM	#1
cebra Registered User Join Date: Jan 2018 Location: Durham, North Carolina Posts: 782	Pros/Cons: Installing Harness before Engine I am debating whether I want to hook up my harness (standalone harness from BP Automotive) to the sensors on the motor before dropping it in or after? My thought is after to keep from accidentally routing the harness some place I can't get it out if needed or pinching it when dropping the motor in...as I look at it, it may be tough to route once the motor is in due to the number of wires running near the bottom of the motor. Thanks for advice. __________________ My Daily Driver Build: http://67-72chevytrucks.com/vboard/s...d.php?t=755668

01-10-2019, 01:55 PM	#2
Macdaddy1 Registered User Join Date: Dec 2017 Location: Niceville Florida Posts: 347	Re: Pros/Cons: Installing Harness before Engine I installed mine after I dropped in the motor and then played with wire routing. However, my cab was off at the painters so it was easy on just a frame.

01-10-2019, 03:42 PM	#3
1971Stepside Almost Satisfied Join Date: Mar 2002 Location: Springfield, MO Posts: 2,932	Re: Pros/Cons: Installing Harness before Engine I put my BP Automotive on after the engine was in. Cab is on, but no fenders. I have plenty of room to work the harness where I want it. It will come off and go back on at least two more times before I am done. __________________ 1971 C10 Stepside. LSx 6.0 with BTR Stage IV, Speed Engineering Headers, 4L80e transmission w/3200 Circle-D Stall. 3.73. Posi. Purchased this truck when I was 17. I started the rebuild (or take apart) in 1993. I have drug it around all over the country in pieces. Finally back on the road in 2021. "I can't complain, but sometimes I still do. Life's been good to me so far."

01-10-2019, 04:16 PM	#4
mongocanfly Post Whore Join Date: May 2015 Location: Alabama Posts: 14,674	Re: Pros/Cons: Installing Harness before Engine I would wait til after install...the only plug that's hard to get to is above the starter....leave the starter off til you get it plugged and the rest is easy....no sense fighting the harness while your installing the engine __________________ Mongo...aka Greg RIP Dad RIP Jesse 1981 C30 LQ9 NV4500..http://67-72chevytrucks.com/vboard/s...d.php?t=753598 Mongos AD- LS3 TR6060...http://67-72chevytrucks.com/vboard/s...34#post8522334 Columbus..the 1957 IH 4x4...http://67-72chevytrucks.com/vboard/s...63#post8082563 2023 Chevy Z71..daily driver

01-10-2019, 05:44 PM	#6
cebra Registered User Join Date: Jan 2018 Location: Durham, North Carolina Posts: 782	Re: Pros/Cons: Installing Harness before Engine Sounds like after is the consensus. __________________ My Daily Driver Build: http://67-72chevytrucks.com/vboard/s...d.php?t=755668

01-10-2019, 05:46 PM	#7
1971Stepside Almost Satisfied Join Date: Mar 2002 Location: Springfield, MO Posts: 2,932	Re: Pros/Cons: Installing Harness before Engine I put mine on with starter in place, but I had the header removed. With the starter and manifold in place it would be tough to do __________________ 1971 C10 Stepside. LSx 6.0 with BTR Stage IV, Speed Engineering Headers, 4L80e transmission w/3200 Circle-D Stall. 3.73. Posi. Purchased this truck when I was 17. I started the rebuild (or take apart) in 1993. I have drug it around all over the country in pieces. Finally back on the road in 2021. "I can't complain, but sometimes I still do. Life's been good to me so far."

01-10-2019, 07:12 PM	#8
sprint_9 Registered User Join Date: Nov 2012 Location: 9 Posts: 862	Re: Pros/Cons: Installing Harness before Engine Keep in mind you can only pass the harness one way through the hole if you use the grommet provided with the bp harness and its 2 1/4 hole or what ever it is. For example, putting the harness on the engine and then dropping it in the frame and stuffing the ecm side of the harness into the cab wont work, the hole is too small for the plugs to fit. You can get 1 or 2 plugs in, but not all. If not using the grommet and passing though the hole then it would be no issue either way.



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