Mick Rae
Active Member
Ran out of day light today, so just having a ponder.................forgive the long post, just feel its best to give all detail. Especially as its something small I have done wrong most likely!
I decided today to check ignition etc - always felt the car was a wee bit sluggish, starts and runs well, but just, well, sluggish a bit. Although I suspected timing, I decided to start by checking everything else. I put the disclaimer in here right now that I am not expert in these matters!
First I checked the dwell - it was 40, so then I checked the points gap, sure enough it was a bit on the big side - set with feeler gauge to 15 thou. Started up, checked the dwell, it was 55 - figured close enough (I am right in thinking 57-60 is the region - starting to doubt myself now!). I checked the ignition timing (strobe) The 8 degrees mark was a bit over (like a good cm) to the right of the pointer (overly retarded right?). So using the A-R adjuster on the distributer I put things to the 8 degree mark lined up with the pointer - vac advance disconnected and plugged, engine idle at 650 rpm (rpm measured on meter, but corresponded well with dashboard rev counter).
Went for a drive................car feels more sprightly, so that's good. But has a weird miss - grand in first gear, then if accelerated hard in second or third, an intermittent miss (like a bit of a stumble really, no backfire, just a sharp stumble/miss), once up to 4th, fine - well, nothing noticeable, cars running lovely......but maybe, just maybe, the miss was there once or twice, hard to say at steady speed). Overrun no problem, but then if overrun in third gear for example, applying throttle causes a couple of 'hics' then fine.
So I went home. I checked the points again - all good. I changed the rotor for a new one - didn't help. Put the old rotor back and changed the distributor cap. Made no difference. Checked the timing again - yup, 8 degree lined up with pointer, as I had set it. I cleaned the coil contacts, the distributor to coil contact. Went for a run. Was same, intermittent miss, well, maybe a little better, but still there.
So now I'm sitting here thinking.
1. what am I missing? (no pun intended)
2. Could closing the points gap cause such a thing to happen, seems doubtful as its now correct and was incorrect before?
3. Could altering the ignition timing be the issue? I remember my old MG needed to be retarded a bit with unleaded (premium) from book figures, but that would pink, not miss, and there is no pinking at all from the Rover............I ran out of daylight as was going to retard back to where I found it, but didn't fancy being at the roadside in the dark, so packed up and decided better to look a fool but get good advice than go round in circles. FWIW, engine has 41K on it. As a wild card, the front end has been raised, and it wasn't driven since, did consider maybe some muck in tank has been moved by sitting at that angle and what I am seeing is dirt in the fuel system, but no, cant be it - has to be something I have done today as regards the above. I will appreciate all your advices, remember, my enthusiasm is not matched by my experience sadly
I decided today to check ignition etc - always felt the car was a wee bit sluggish, starts and runs well, but just, well, sluggish a bit. Although I suspected timing, I decided to start by checking everything else. I put the disclaimer in here right now that I am not expert in these matters!
First I checked the dwell - it was 40, so then I checked the points gap, sure enough it was a bit on the big side - set with feeler gauge to 15 thou. Started up, checked the dwell, it was 55 - figured close enough (I am right in thinking 57-60 is the region - starting to doubt myself now!). I checked the ignition timing (strobe) The 8 degrees mark was a bit over (like a good cm) to the right of the pointer (overly retarded right?). So using the A-R adjuster on the distributer I put things to the 8 degree mark lined up with the pointer - vac advance disconnected and plugged, engine idle at 650 rpm (rpm measured on meter, but corresponded well with dashboard rev counter).
Went for a drive................car feels more sprightly, so that's good. But has a weird miss - grand in first gear, then if accelerated hard in second or third, an intermittent miss (like a bit of a stumble really, no backfire, just a sharp stumble/miss), once up to 4th, fine - well, nothing noticeable, cars running lovely......but maybe, just maybe, the miss was there once or twice, hard to say at steady speed). Overrun no problem, but then if overrun in third gear for example, applying throttle causes a couple of 'hics' then fine.
So I went home. I checked the points again - all good. I changed the rotor for a new one - didn't help. Put the old rotor back and changed the distributor cap. Made no difference. Checked the timing again - yup, 8 degree lined up with pointer, as I had set it. I cleaned the coil contacts, the distributor to coil contact. Went for a run. Was same, intermittent miss, well, maybe a little better, but still there.
So now I'm sitting here thinking.
1. what am I missing? (no pun intended)
2. Could closing the points gap cause such a thing to happen, seems doubtful as its now correct and was incorrect before?
3. Could altering the ignition timing be the issue? I remember my old MG needed to be retarded a bit with unleaded (premium) from book figures, but that would pink, not miss, and there is no pinking at all from the Rover............I ran out of daylight as was going to retard back to where I found it, but didn't fancy being at the roadside in the dark, so packed up and decided better to look a fool but get good advice than go round in circles. FWIW, engine has 41K on it. As a wild card, the front end has been raised, and it wasn't driven since, did consider maybe some muck in tank has been moved by sitting at that angle and what I am seeing is dirt in the fuel system, but no, cant be it - has to be something I have done today as regards the above. I will appreciate all your advices, remember, my enthusiasm is not matched by my experience sadly