MPG

[chrisyork]

Mmm That's interesting Lee. What distributor is your engine running? It almost sounds as if there is something awry there. Perhaps vacuum advance not working? Or perhaps the centrifugal advance has shed one of the springs so kicking in too early?

Chris

 

[SydneyRoverP6B]

LeeEFI wrote,...

A slightly dissapointing tune-up session today. I tried your method Ron, initially with great results; smoother; more responsive etc. But the starter didn't like too much advance (slow turn-over). So I had to retard the ign again, but I was able to get it a tad more advanced than before. So some improvement The only way to run it at full ign advance would be to fit a HT starter motor, which I had tried before, and wasn't that over-enamoured with it.

Hi Lee,

Yes that is rather disappointing that the starter motor is being difficult. Do you know for certain that TDC on the pulley actually corresponds with #1 piston actually being at TDC? Reason I ask is that Rover was less that accurate on more than one occasion when it came to this, and while some pulleys will have TDC where it should be, many won't. So if your TDC marking is actually advanced of that, then all the markings will be out, so 12 degrees BTDC might actually be 20 degrees BTDC purely as an example. This would certainly impact on the starter motor's ability to turn the engine over.

What were the timing marks showing when the engine speed plateaued?

I am pleased to know though that it did indeed make a difference, and that there was an improvement..

Ron.

 

[LeeEFi]

Mmm That's interesting Lee. What distributor is your engine running? It almost sounds as if there is something awry there. Perhaps vacuum advance not working? Or perhaps the centrifugal advance has shed one of the springs so kicking in too early?

Chris

Hi Chris,
The dizzy itself is a fairly recent (two years old) reproduction unit based on the DLM8, and is specced for a 3.9 litre. To be honest it has junked the ignition amp already. I replaced that with a second hand unit that I was lucky enough to have. Apart from that it's worked very well. It look's like I will have to check that (advance springs) idea out as a matter of course

 

[LeeEFi]

Hi Lee,

Yes that is rather disappointing that the starter motor is being difficult. Do you know for certain that TDC on the pulley actually corresponds with #1 piston actually being at TDC? Reason I ask is that Rover was less that accurate on more than one occasion when it came to this, and while some pulleys will have TDC where it should be, many won't. So if your TDC marking is actually advanced of that, then all the markings will be out, so 12 degrees BTDC might actually be 20 degrees BTDC purely as an example. This would certainly impact on the starter motor's ability to turn the engine over.

What were the timing marks showing when the engine speed plateaued?

I am pleased to know though that it did indeed make a difference, and that there was an improvement..

Ron.

Hi Ron,
I will have to check the timing marks with a strobe light to check that possibility. To be honest, I adjusted the timing with the aid of a tachometer and not a strobe light - as my strobe is at another place :roll: Also as I've had this engine in and out more times than I can remember, it could be a possibility that I could've replaced the dizzy one cog out :?: But...I took the SD out for an extended drive today, and found it drove and run beautifully I'm sure this was down to the extra advance from sundays tuning efforts. On my 70mile drive today I found it to be using about a quarter of a tank. Although an accurate mpg test will have to be done, I'm delighted at the performance of the K&N air filters and BBW needles compared to the ghastly BCA's. It's actually a pleasure to drive now 8) Cheers :wink: