MG Sports Cars

My father and I have completed the engine swap and we are currently trying to start the car. We used the original wiring harness that came with the MGB. The motor that we are using is from a 1984 2.8 Jeep. We are using a carburetor for the intake, thus no computer.

Here are the details, our battery works, we have it hooked up to a battery kill switch in the trunk which is connected properly and grounded. The power makes it all the way up to the starter motor (according to the test light) and then stops there. Connected to the starter is 3 brown wires on the "Solenoid" bolt and one connected to the "battery" bolt which leads to the battery and one green and white wire connected to the "Relay" bolt.


The engine is giving no response and none of the dash components are getting any juice, its just dead.

We are using a Haynes service manual for the MGB and a Chevy service manual to compare and contrast. If any one has a schematic that could be useful or any suggestions, that would be wonderful.

Thank You

-- Nick

You can get schematics for MG wiring at www.advanceautowire.com. "Stock Schematics" link on the menu on the left side of the page. Note there multiple pages; watch the year reference in the bottom right of each page (that threw me the 1st time I looked at them).

Thank you, I'm checking it out right now. I'll let you know how it goes for us as soon as we have tried all that we can think of.

Thank you again

- Nick

The wiring is coming along pretty well. Thank you for that reference, it made a huge difference while we were comparing it to the haynes schematics. We now have the car turning over, in fact we had it running yesterday. We are now having trouble with the timing and keeping it running.

Here's what we are using on the engine:
4 barrl carb with mechanical choke, edlebrock mid-range cam shaft, a two wire connection distributor, a delco alternator with a Batt. stud on the back side and a port with two connection prongs labeled R 1 and R 2. we currently only have two wires hooked up to the batt. stud on the back of the alternator which are the two that are directly connected to the batt. stud on the starter solenoid, but nothing on R 1 and R 2 prongs.

I looked over the Bentley schematic and it proved to be quite useful, but if any of these componets ring a bell to our problem, We would greatly appreciate any advice.

The car is also draining our car batteries abnormally quick from trying to start the engine.

Thanks for your time.

- Nick

When you had it running, how did it run?

Sounds to me like the alternator is not hooked up right. You have it wired like a single wire alternator. Sounds like a 3 wire. Double check to be sure, but if memory serves, on a GM delco alternator R1 is for your alternator light; R2 is your exciter wire and the large stud goes to the battery (or battery post on starter solenoid which is then connected to the battery). The exciter is a wire from the fuse box that's hot when the ignition is on (suitably gauged; my after market harness had it at 14 GA if I recall).

It ran with a smooth idle after we adjusted the distributor a little bit, but died in less than a minute. When we are trying to start it, it only takes about 6 solid "key turns" to kill the battery. We are going to try to work on this right now, thank you for all of your info. I'll keep you posted.

- Nick