Autometer Gauges in an S2

[DreamsOfA47]

Hello all,

Has anyone replaced their gauges with Autometer products? I've decided that I'd replace a few of my broken ones with Autometer products as I have them in my race car and I really like them, but I'm already running into issues getting them to work 

I got an oil pressure gauge (#2634) to replace my non functional one (the stock gauge reads that pressure exists, but does't read any particular number under normal driving conditions) and a temp gauge (#2635) so I can read it in F and I can't get either to work. The oil pressure gauge just bounces and the temp gauge reads 150 at idle, cold, and the the needle approaches 0 when the revs are increased.

I also have an Autometer Tach (#2677) I'm wanting to replace my absolutely fried one with but I haven't attempted that yet.

Has anyone gotten Autometer Gauges to work in a Europa?

[BDA]

Are you using the Autometer senders?

[DreamsOfA47]

I have yet to swap the sending units over. I figured that the signal should be the same but is that maybe not the case? On that note doe anyone know the thread pitch of the water temp and oil pressure senders? I'm aware I may need an adapter to make them work.

[BDA]

As you found out, that's a bad assumption. The Autometer gauges probably don't work the same way as the Smiths do at all and if they did work the same way, it's probably unlikely that the Smiths senders would be compatible with the Autometer gauges. If you're curious about how the Smiths gauges work, you can see this page (http://lotus-europa.com/manuals/misc/electrical/meterinfo.html).

I only have electric temperature gauges and the Smiths senders I have for my TC - I expect they would be the same for all Smiths gauges - have 1/8 NPT threads. I don't know about the pressure senders. You'll have to pull it out and measure the threads yourself I think. I don't know if this can fit into your plans or budget but I might use a mechanical oil pressure gauge just so your oil pressure knowledge is not dependent on your electrics.

[DreamsOfA47]

Swapping out the seiners will be my next big project after this SoCal rain stops! I am very curious so that'll be an interesting read. It makes sense that the senders ay not be compatible.

1/8"NPT is a great place to start! Considering the troubles I've been having w/ my rad fan the temp is what I'm most worried about. When my oil filter arrives I'll be able to pull the pressure sender as I'll already have the oil drained  while I'm changing it. I agree that a mechanical pressure gauge would be preferred but I'm not yet at the point in the project for the gauges and set up I'm really wanting is these gauges are going to hold me over for the near-medium term. I'll update the thread with how it goes once the senders are swapped!

All this has me wondering about the new tach and what I may need to do to make it compatible with my wiring. I have an Autosparks brand S2 harness in the car and I know the tach leads have bullet connectors for the original tach so I know it'll need some modifying at least...

[jbcollier]

The Europa fuel and temp gauges are powered through an instrument voltage regulator.  Autometer gauges work off system voltage.  Renault engines have metric threads for their sending units.  It's all easy to sort but not plug and play.

[DreamsOfA47]

I figured that the senders would be metric in a French engine. Does anyone know the thread pitch? If not I guess I’ll give RD a call tomorrow and see if they happen to know or are able to find the thread pitch for me. There’s an awesome industrial hardware store locally that’s bound to have an adapter for me from 1/8”NPT to whatever it is the Renault uses. I was hoping it’d be more plug & play than this but it’ll be worth it to me.

If the new gauges don’t require a voltage regulator due to running off system voltage instead of a conditioned 10v instrument voltage then I can just eliminate the regulator from my wiring, yes? Or am I making another incorrect assumption?

[jbcollier]

The answer is yes BUT first you read the instructions that came with the gauges and follow them.

Smiths instrument voltage regulators come in three flavours:
- mechanical 10v
- mechanical pulse system voltage
- electronic 10v

The middle one in particular will play havoc with modern gauges.

Making up adapters is pretty easy.  Just get a short bolt or plug in the metric thread and drill and tap it to the required thread.

[DreamsOfA47]

I may be silly and inexperienced but I do all I can to RTFM when I'm working with new equipment! 
I hooked the gauges up per the included instructions but I didn't know that there were different methods of gauge signaling I needed to account for. I get to learn something new every day!

I have the old small, rectangular voltage regulator that I believe is a solid state, mechanical 10v regulator, that is original to the S1. JB do you know off the top of your head if that is, in fact, a mechanical regulator? I'll begin research soon but often you know these things.

Are the metric threads from the Renault senders not some form of tapered pipe threads? Are they just regular style threads?

[DreamsOfA47]

Small update: while on the phone with RD Enterprises discussing other parts, I asked if they new of the thread pitch of the senders for the oil pressure and water temp and they did! Oil is 14mm and water is 18mm. They had adapters for the respective metric to 1/8" NPT so although I certainly overpaid I had them include them in my order for convenience's sake. It saves me on time and gas not having to head to the hardware store I trust because I'm not overly confident in making an adapter myself. I'll update this thread when I'm able to get the senders swapped out to see if I can make the gauges function properly.

[BDA]

Try not to feel bad about overpaying. You're supporting a valuable Lotus parts supplier! 

[DreamsOfA47]

I agree fully! They've done very well by me every time I've needed anything from them, from questions to parts and my heart loves supporting them. My wallet, however does NOT

[jbcollier]

Couldn't say if the original instrument VR regulates or pulses.  It all works out the same for the original gauges.

The Renault engine uses straight thread and sealing washers rather than pipe thread.