1987 tbi

[Leonard1]

Hey guys, I bought an '87 r10 without the drivetrain. I have a complete '95 tbi that I got with a bunch of other parts last year, and I want to put it in the '87. I've done a couple of searches, and I think the engines are virtually the same, but I'm wondering what I'm going to run into as far as the ecm and wiring. Since this truck doesn't have a motor, I don't have anything to go by, and it looks like part of the harness was cut... Any help would be greatly appreciated!

[kwmech]

Everything should transfer over as both were TBI. Don't know of any major differences

[Leonard1]

That's what I thought, based on my search. So I guess I should look for a harness for a '95? Would they be the same?

[Leonard1]

Can someone tell me for sure what years wiring harness will work? I think there are going to be some differences in the transmission part.

[burnin oil]

I think you will have to do some pin out adjustments. On the 88+ trucks they changed up the wiring some a couple of times. I know the EGR changed and I think it was mostly emissions equipment. I know that they used a couple different ECMs. The 87 may have been a big cap distributer. I would get the wiring diagrams and go from there. The swap itself is straight forward.

[Leonard1]

Originally Posted by burnin oil

I think you will have to do some pin out adjustments. On the 88+ trucks they changed up the wiring some a couple of times. I know the EGR changed and I think it was mostly emissions equipment. I know that they used a couple different ECMs. The 87 may have been a big cap distributer. I would get the wiring diagrams and go from there. The swap itself is straight forward.

Thanks for the help. Where would be the best place to get a reliable wiring diagram? From what I have googled, the same ECM was used from 87 to 92

[burnin oil]

I am sure there are a few wiring diagrams on the web but if not the factory service manual is excellent but even a Haynes manual should work.

[67 Burb]

I was looking to do the same thing a few years back and found that the 95 used a few different plugs. If I recall, things like the TPS and maybe others as well. Not a big deal, though.

I have a 1988 GMC and a 1995 Chev wiring diagrams. PM your email and I can send them to you,

[Leonard1]

PM sent, thanks for the help

[Leonard1]

The engine I'm installing didn't have the idler pulley, so i bought one for it, but I still need the spacer and bolt. Anybody have a source, I can't find one on the web. Junkyard my best bet?

[67 Burb]

Originally Posted by Leonard1

Can someone tell me for sure what years wiring harness will work? I think there are going to be some differences in the transmission part.

Are you using the 4L60E tranny from the 95? If you are, you would do best to use the wiring harness and ECM from a 95. In the 95, the ECM controlled the tranny. The 4L60E in 95 has slightly different wiring than even the 93 or 94 (can't remember what year the extra wire appeared). I think there was one more wire in the 95 tranny harness.

[Leonard1]

Originally Posted by 67 Burb

Are you using the 4L60E tranny from the 95? If you are, you would do best to use the wiring harness and ECM from a 95. In the 95, the ECM controlled the tranny. The 4L60E in 95 has slightly different wiring than even the 93 or 94 (can't remember what year the extra wire appeared). I think there was one more wire in the 95 tranny harness.

Actually, I bought an 89 tbi motor and 700r4 earlier in the week, and I think I'm going to use it instead of the 95. And it came with the engine wiring harness cut at the same place as the one in my 87. Seems to be in great shape, and I think it will make things easier. Should be the same computer and wiring, according to the wiring diagram you sent.

[67 Burb]

I believe the 89 used the #1227747 ECM.

[Leonard1]

Originally Posted by 67 Burb

I believe the 89 used the #1227747 ECM.

I think that ecm was used from 87-90, according to google. I found a 1227747 ecm pin diagram, and all the colors and locations match my truck. I hope it is the same, I got the wiring harness soldered back together this weekend.

[67 Burb]

Originally Posted by Leonard1

I think that ecm was used from 87-90, according to google. I found a 1227747 ecm pin diagram, and all the colors and locations match my truck. I hope it is the same, I got the wiring harness soldered back together this weekend.

That's great. How many wires in that bundle?

[Leonard1]

Originally Posted by 67 Burb

That's great. How many wires in that bundle?

Actually, I think there were 24 cut...
Thanks again for all your help on this. I'll be sure to report back how it turns out.

[Leonard1]

After a little troubleshooting, I got it fired up! I have another question: The ac compressor was on the driver's side originally, and on the new motor it is on the passenger side. Any suggestions on ac hoses? It looks bad with that much slack.

[67 Burb]

Originally Posted by Leonard1

After a little troubleshooting, I got it fired up! I have another question: The ac compressor was on the driver's side originally, and on the new motor it is on the passenger side. Any suggestions on ac hoses? It looks bad with that much slack.

Too bad you're not just down the road. I just dropped a 5 L from an 89 Caprice into my 51 Pontiac and I'm not using the factory A/C hoses. They are sitting in my garage waiting for me to decide what to do with them.

I think you can get the hoses shortened and there are special hose clamps for A/C hoses. Talk to someone who does A/C repairs.