The 'E' Type Forum

Andrew, in improvement from 0.7v drop to 0.2v drop is good, but it does not explain why the voltage was down around 7 volts. Maybe it is simply the battery going bad.
Tom

Andrew, FWIW, the LED should have had nothing to do with the original generator system not working. The indicator bulb in that system does not feed the fields or in any other way effect the charging, it is merely an indicator between two wires. It also surprises me on the new alternator in generator...

Did you ever find way you only had 7volts?
Tom

That reading does indicate a problem but not where: 1. Bad battery. Place a voltmeter on the actual battery pos and neg posts and crank. If 7 volts, probably bad or discharged battery. A 3.8, so assuming positive ground. 2. Place voltmeter leads between battery position post and engine block. Crank....

From where to where did you read the 7 volts?
Tom

You responded while I was still making additions, did you see my thoughts on the wire crimp?
Tom

Andrew, you certainly have a frustrating situation. Now that you have gotten rid of the original generator and voltage regulator, you really have a completely different system than before and possibly a different problem. However, I do see two items that could be similar. 1. Generator/Dynamator grou...

Johan, based on what you describe, I would suggest the MC first, which you already addressed. Next brake fluid, which you addressed. Last the slave/servo cylinder which fixed Malcom's. My only further question would be, if it is the slave/servo, I would be expecting the one reservoir to fill and the...

Go with post #2 above, being sure the points are closed when you make the measurements.
Tom

This article may help:

https://forums.jag-lovers.com/t/water-t ... nce/427836

The fuel and water will be similar
The oil pressure sender is not a variable resister and cannot be checked with an ohm meter.
Tom

Air in the system is the first concern. More details. Does it do it even sitting still without the car moving? How long must one wait from the two pumps that bring the pedal up until the pedal now drops low? If not air I would suspect a caliper piston is retracting too much. If the problem only occu...

The roll pin must surely have been added in an attempt to prevent the bearing rotating, but I've yet to find anyone with any engineering understanding who thinks it's a good idea. https://i.postimg.cc/DyNsHVhc/4-2-Release-bearings.jpg Mistakes are made, but clearly the engineers at the manufacturer...

Your original system would have had a generator, and the red ignition light was powered by that system. Any alternator system will be different. If you do indeed have an 11AC unit, yes, you could add a 3 AW to power the red ignition light. If would be wired just as in the 4.2 with alternator. Howeve...

To be clear, the oil pressure gauge, as original, operates from battery voltage. It receives this battery voltage off the INPUT terminal on the dash voltage regulator, not from the regulated voltage of the dash voltage regulator.
Tom

Richard, here is a write up on how the reaction valve works if you are interested: https://forums.jag-lovers.com/t/brake-issue-reaction-valve-slow/371019/36 When you say you replace the reaction valve, what all did you replace. The "kits" that I have seen do not include the poppet, #8 in SNG's parts...

The alternator will work with the field + and field - in either position. However, in theory, Lucas recommended the position of the wires as they did for a reason. Because of the geometry of the brushes on the slip rings, one brush travels further and faster than the other. Because the electrons tra...

It seems that you have an early 4.2, and those did not use the 3AW. The 3AW uses the AL post on the alternator. Since yours may not have the 3AW, you would not use the AL post. Your ignition light on the dash is probably controlled by an oil pressure switch (not the same as the oil pressure gauge se...

Again, thanks for your thoughts. I guess we just have different opinions of "glaring oversights."
Tom

Marek, Sorry you had to write so much. I understood what is going on and why- the fluid exchange is quite obvious. That is not what I was asking. I was commenting that if anything it may be good that the fluid levels are changing as that helps to alert one to the fact that a seal is leaking. Althoug...

It's a glaring oversight on the part of the designers that they placed reservoirs at different heights. kind regards Marek Marek, not sure I follow. It seems if the slave seals are leaking, one would want to know so the problem can be resolved. Why would this being an indication be a glaring oversi...