MG T-ABC

I believe I have found the reason for my hot running and lack of power.

My distributor appears to have been installed 180 degrees out from correct. I checked the timing with a strobe light and found it running at a degree or two past TDC and the micro adjuster at full advance to get to that setting. The plug wire from the cap that is farthest away from number one cylinder is the lead that is sending spark to the number one cylinder. I have no idea when this happened but it likely been running this way for quite some time. For me, normally, that lead would be the lead that supplies cylinder number 4 with spark.

My question for all of you is this, is there anything I need to be careful of when dealing with this distributor? I know that there is a gear, instead of a pin, at the bottom of the shaft that must be encouraged to mesh on the reinstall and that makes me wonder just how you make sure you are meshing at the right point. My plan is to remove the distributor and reinstall with rotor pointing to number one cylinder with timing marks at the front of the engine lined up at TDC. I'll have the micro adjuster at midpoint and then do a static timing before a running fine adjustment. Fingers crossed!

I did notice the plug lead arrangement a while ago and thought it needed looking into but as the car was not on the road yet just continued to solve more pressing issues first.

Thanks in advance for any advice on this next bit of work. Report to follow once completed.

Lynn

The orientation of the distributor body won't matter so long as the plug wires are correct. Sometimes people rotate the distributor body to move the coil wire terminal away from the tach drive. If you want to move it back, just rotate the body exactly 180 and move the plug wires two ports each at the cap. You won't even have to remove the distributor. That said, I think your only issue is that there isn't enough advance. Modern fuels require at least 5 degrees BTDC on these engines. 7-8 is usually better.

Hi Steve,

While I understand what you are suggesting I am somewhat confused as at the moment I cannot even get to a TDC spark with the micro adjuster at full advance. I loosened the nut on the back of the micro adjuster to try to rotate the body but the body did not seem to want to rotate at all. The front bolt fixes the micro adjuster and I see nothing else that looks like it would lead to a body that could be rotated into position. That leads me to think I have to remove it and then drop it down in at a point that leads to the ability to adjust the timing with the micro adjuster. My thought at the moment is that it needs to go one additional gear tooth clockwise (advanced) to allow for correct static timing.

I'm hoping that when you say rotate the body, you mean physically remove the body from the block and rotate it. When you say distributor, you are talking about the plate within the body and it gets left alone. If that is correct then we are on the same page and I am on my way.

I do not disassemble anything till I have a fairly clear path and understanding about I want to accomplish and how to get there. I'm pretty happy to have this resource available.

Lynn

I do not think Steve is suggesting pulling the distributor out from the block.

To adjust timing, look for the main lockdown bolt, that locks the distributor into the block. See pic. Takes a 1/4 Whitworth socket which is the same as 5/16 BS. Once you loosen that a little bit, you can center the micro-adjuster and then re-set the timing to where you want it.

What really can throw people off is using the magnetic sensor like Petronix, or the optical sensor type electronic ignition. Whenever you switch from electronic to normal points, or vice versa, it will throw the timing off as much as 30 degrees.

Sometimes the clamp gets overtightened and makes it difficult to rotate the distributor. Loosen the clamp and also the bolt that Duncan shows. It should turn. If not, try prying the clamp open a little. Failing that, pull it out and repair on the bench.

Nicely done guys. Thanks a bunch. Comments and picture answered questions. Everything very very tight. Too much so from my experience. Spent a few moments before dinner working at getting things loose and finally got some rotation. No bleeding involved either.

We have a very nasty weather day headed in tonight for all day Wed so guess it looks like garage doors closed. Heater and music on. Hot cup of tea and have a second go at getting the timing correct. I'll post an update Wed afternoon or night depending on how things go.

Lynn Dykgraaf