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MG TD TF 1500 - XPEG misfire above 4500 rpm
|My TF1500 has a misfire above 4500 revs which I have traced to my distributor(I think!). There is a slight movement between the body and the shaft housing and a 50 thou end float in the drive shaft. Could someone advise me as to the correct end float and if I simply insert washers and how I might tighten the body.|
I suggest that you try a couple of different, new condensers first - if you have not already done so.
|F. B. Travis|
I recommend fitting pertronix electronic ignition, which will not be affected by a worn/loose shaft. I got mine from Skip Kelsey at Shadetree Motors. http://www.shadetreemotors.com/
|Mike - There should be a spacer between the body of the distributor and the drive gear to control end float. I don't know what the recommended end float is, but 0.050" is excessive in my opinion. The other issue is a loose bowl where it is pressed on to the shaft housing. Peening with a center punch around the periphery of the bowl to shaft housing interface should tighten things up (by the way, that play will cause misfiring).|
Good luck - Dave
|Before you replace your distributor, you may want to consider your fuel pump. If the pump can't keep up with the consumption she will misfire like a mother! What I guess we need to know is if this came on slowly or if it suddenly stated. Perhaps the fuel filter is restricted?|
I gotta go with Ron regarding inadequate fuel flow.
Another possibility, if you haven't done so, you might also want to check that your points gap hasn't closed up.
|Greg Van Hook|
|The "wobble" of the body on the shaft causes the point gap to vary at high RPM, thus the missfire. The Pertronics Ignition will releive this somewhat since you no longer have the variable spring pressure from the points as the shaft rotates. |
The cure is to have the body re-swaged to the shaft (the punch peening rarely works for long).
The only one I know that has the special tool for doing this is Blair Engle (phone 850-385-2821) I can't find his email address just now but I think it is firstname.lastname@example.org
Blair has restored my TF distributor this way, it was in bad shape after being peened several times.
|"Another possibility, if you haven't done so, you might also want to check that your points gap hasn't closed up."|
Umm... I caused high-rpm misfire by gapping the plugs too big.
Standard ignition, standard coil - mine don't like more than 0.6mm gap.
(recommendation I got was 0.5mm, was trying 0.8-0.9mm. Seemed more lively at low revs though.)
This thread was discussed between 09/10/2004 and 12/10/2004
MG TD TF 1500 index
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