Lotus Elan +2 Rev Counter

I have a 1969 Elan +2 which is running now as negative earth with Lumention.
The revcounter which has worked without issue in the past, has now developed a fault where it comes alive after 45 minutes of the engine running. From cold it does not operate at all. I have checked all connections and earthing which tests out ok.
Before I look for a replacement unit does anyone out there have a view or has had a similar malady.

Thank You
EAN

Aha I see you’ve found Elan.net
I suggest that you give your problem a “search” here, it’s been covered in depth & all of the answers are there.
Having once done that & not finding the answer you need, you’ll get the help you need here.
Cheers
John

Nice Welcome to a newbie!

EAN - you are very welcome here as I’m sure 99.9% of the members will agree. Hope the first reply you got didn’t put you off, we’re not all crotchety old bu**ers honestly. I wish I could answer your question but I hope someone will be along shortly to point you in the right direction.

DJ - do you remember you were new to this once. It’s nice to treat people how you would like to be treated. I’m surprised you haven’t tried to answer the question as you are very quick to answer just about every other thread there is on here.

I don’t know exactly what you are running, but this is a common problem when changing from points to eletronic ignition, the simplest fix is to get you rev counter converted from RVI to RVC -speedy cables fo excellent work here for a reasonable price. Your rev counter still looks the same, it just gives an accurate reading again.

Could you explain what that means? I’m interested since I’ll also be using electronic ignition.

I’m no great expert on the electronics - but

RVI current loop system (with points) 2 white (+ive ignition) cables go into the rev counter
to RVC earth pulse system which will work with electronic ignition (or points) previously mentioned cables are connected to each other and a -ive come from the coil to the rev counter

If like me you are running an ECU rather than either of the above, you will need a wasted spark system which can still look the same but because a spark is generated every stroke, it is calibrated to “ignore” half the sparks

Thank you for you kind reply.
All the Best EAN

Thank you, checked out the Speedy site tonight and it looks just the job.

All the Best from Sunny Scotland EAN.

Ok to be fair my answer might have sounded abrupt without some foreplay, but I read of his problem on the LDC forum & pointed him in the direction of LotusElan.net where I new that he would find all of the answers.
The problem that was described has been well documented in the net archives.
I have not had any involvement in the problems caused by Lumenition on the Tacho but lots here have.
I do not attempt to answer anything which I don’t have some personal experience of, or don’t know the answer to.

Here’s the reply as it appeared on LDC Forum:-

[i]It’s the Luminition that’s causing your rev’ counter problems, a replacement Tacho’ won’t cure the problem but replacement internals that do function properly with luminition will.
There are wiring tricks that can solve the problem.
I’m not up to speed on the solutions but do know that you are not the first to encounter this problem…

Now I’m running scared; my Taxi will be here any minute so just use the info’ I sent on the door lock thread.
[/i]
So stuff that in your pipe and smoke it :laughing: :laughing: :laughing:

Cheers
John

Does anyone understand enough about the managed a RVI/RVC issue to be able to say whether a DIY conversion is possible?

Mike

I did it.

I just fitted electronic ign system also (Luminition Magnetronic) and was expecting to have the rev counter issue. I am amazed to report I dont. Yahoo… Brill. I won one. I am very pleased with the result too. Car is noticably smoother. Fluffyness has gone and the tendancy to missfire also gone… :slight_smile: :slight_smile:

Just a slight hesitation when opening the throttle to sort out now. L/H Carb acc’ pump is either too rich or not enough. Going to lift off the carbs again and check out the little squirts.

Welcome Ean. Again from not quite as sunny Scotland…

Send that rev counter to speedy as previously posted. That will sort it for you.

Keep us err…Posted… :laughing:

Alex B… :sunglasses:

Frank,
do let us in on the secret, what is involved?

Mike

Alex, Thank you for the update, I checked out the Speedy Website and it looks like the ideal solution. I had a prompt reply from the Lumenition manufacturers also whi have a bulletin on this which also recommemnds the Speedy route.
All the Best EAN :smiley: :smiley: :smiley:

Mike,

It’s really not that big of a secret. After experiencing some frustration with two of the shops that do the conversion, I sat down one day and thought about it. Pretty much every car manufactured during the past 25 years has electronic ignition. Half of those cars have tachometers. Those tachometers don’t seem to have the issues that ours do. So I went down to the junk yard and selected a tach that had the same 270 degree swing from 0 to 8,000 rpm. I then yanked out the guts and swapped them into my tachometer body. Of course, a couple of adapter plates had to be made to allow the whole thing to be screwed together properly. I then wired it as Memnon described above. I’ve had no tach issues since.

Frank,
thanks, I was wondering whether the specialists replace the whole mechanism of whether they simply replace/add a few components. I have a spare unit so I may try myself.

Mike

Mike,

Nisonger modifies the existing components. Their conversion doesn’t work. APT Instruments replaces the entire guts. He is 5 miles from my house however he’s also a jerk so I won’t deal with him. Now you know why I did it myself.

Sorry to butt in on the Elan section, but it does say +2 in the title. RVI is a voltage triggered device, RVC is current triggered. I am not an electronics engineer, but the move from points to electronic devices made the voltage ‘pulse’ at the coil too narrow for older Tachos to read accurately. RVC devices are not affected by the narrow (more accurate) pulse of electronic ignition systems so are the way forward. There are DIY solutions, which I will not detail (because I can’t), so I went for a simple ‘send it to an expert’ solution. Speedycables in Wales, UK (although for some strange reason they keep the ‘London’ tag in their name) offer a reasonably cheap solution, conversion and refresh (passivated plating and general clean up, including dial). They even included a correct new square section gasket when they sent it back.

Several others do a similar service (Richfield for one - also do ambient temp gauge refills)… What I was impressed with was a guaranteed calibration service, so that an indicated 6,500rpm really is 6,500, not 7,500 (can a DIY conversion offer this?). I suffered with a bouncing tach for 5 years and wish I had spent the money 5 years earlier! Simple problem, simple solution - and cheap compared to many Lotus ills. Not sure what international postage costs are for Speedy cables et al, but it is a simple solution that local experts should be able to solve (without being jerks!).

Google the problem, it is not only Loti that suffer.

Jeremy
PS no connection any suppliers, other than as a user.

Thanks Jeremy, I will be taking the Speedy route for a solution.
Best Regards EAN