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Posted: Tue May 15, 2007 9:49 am
by Rob_Jennings
slight red light when idle is normal, as long as it goes out with a tiny increase in engine speed you are OK. If its bright red at idle or you are having to rev it hard then you have a problem.

if the fuel gauge dropped when you connected the other wire then you must be over loading the 10v regulator behind the speedo, check the wiring and consider putting a second regulator for your seperate gauge or you can replace the original one for something newer or beefier (1A solid state regultor is just a few pennies in Maplin)

Posted: Sat May 19, 2007 9:03 pm
by steve4063
my rev counter i've got has 3 connections on the back.
a earth as its attached to the body

b is a spade terminal
c is a bullet terminal.

is was told earlier that i ahve to take a wire from the coil?

which terminal is it from + or -
and which one does it go onto and which one is the other for.

thanks its a smiths by the way

Posted: Sun May 20, 2007 12:07 am
by Packedup
From memory, you have the earth spade (soldered to the body), pos spade (has a bit of plastic insulation if you look closely) and the bullet is the coil signal, taken from the neg (dizzy) side of the coil.

If you think about it, the pos/ ign side of the coil always has 12v, so the counter would struggle to work if you ran the wire from it!

Posted: Sun May 20, 2007 7:52 am
by alex_holden
On the subject of rev counters, what is regarded as a sensible RPM limit for a standard 1098 engine?

Posted: Sun May 20, 2007 10:52 am
by Dominic
I understand that the crank self-destructs at 6,500 rpm!
My partner's daughter has a Mini (998cc) and that is red-lined at 5,500 or thereabouts. I wouldn't be happy taking mine above 5000, even when fully run in.

Posted: Sun May 20, 2007 4:18 pm
by alex_holden
Dominic wrote:I understand that the crank self-destructs at 6,500 rpm!
My partner's daughter has a Mini (998cc) and that is red-lined at 5,500 or thereabouts. I wouldn't be happy taking mine above 5000, even when fully run in.
Looking at the peak power output figures on the BMC A series engine page on Wikipedia, it shows the standard Minor 1098 engine developing a peak of 48BHP@5100RPM, but the 1098 Spridgets develop 59BHP@5750RPM. The rev counter I'm thinking of buying is from an MGB and the scale goes orange at 5500 and red at 6000.

Posted: Sun May 20, 2007 10:22 pm
by Packedup
alex_holden wrote:the 1098 Spridgets develop 59BHP@5750RPM. The rev counter I'm thinking of buying is from an MGB and the scale goes orange at 5500 and red at 6000.
Either my rev counter is fibbing, or the fact the engine can't reach 5750 is why the car seems so slow!

Then again, even an A series will start to struggle after nearly a decade of 5k a year of no servicing whatsoever I suppose.

But yes, A series engines do make max power past the point a lot of people lose their nerve, the 1098 can peak safely at around 6500 IMO (though only when quickly going up the box, I wouldn't dream of holding that for more than a split second) and the 998 can handle a bit more. I wouldn't want to take a 1098 over 6k even in first however, unless it had got a rubber cored damper pulley (I bought one last weekend, no idea where I've put it though), been properly serviced and was basically well looked after.

I did once break a 1098 crank, but the autopsy suggested I was doing nearly twice the red line at the time... :oops:

Posted: Mon May 21, 2007 11:19 am
by steve4063
right i connected the earth to the earth
the mains coming out of the regulater to the spade terminal
and the - on the coil the the bullet terminal.

:cry:
nothing happened the needle didn't move an inch until i rocked the unit and it wiggled slightly but still never moved.

do u reckon its busted or have i done something wrong.

the wires on the coil are white and maybe red looks like someone has painted a bit of red on it.
and the white and black to the - terminal on the coil is this right also

also checked the earth ok
mains 11 volt
bullet 12/13 volts

Posted: Mon May 21, 2007 11:29 am
by alex_holden
Are the car and the counter both negative earth? I'm not sure that rev counters need to be powered via the voltage regulator. One of the coil terminals is connected to the side of the distributor - that's the one you want to take the sense signal from.

Posted: Mon May 21, 2007 11:46 am
by steve4063
yes they are both negative earth

i was told that i needed earth power and power from the coil

i'll try it without the power and see what happens

Posted: Mon May 21, 2007 12:02 pm
by alex_holden
I meant I don't know if the power supply needs to be regulated. It certainly needs to be powered, but it might be designed to run from the full battery voltage. The coil connection is so that it can sense the engine speed by how often the spark plugs are firing.

Posted: Mon May 21, 2007 12:18 pm
by steve4063
tried it with diretc power not regulated still nothing :x