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Discussion Starter · #1 ·
Here's the kit, parts list and instructions

Thanks to Rob (who pointed out the obvious vacuum source, DOH!:wallbang: ), I re-invented the whole thing and it is working great for me. One hour ride yesterday that was nice and cold. Heat comes on very quickly after switching out of bypass mode. Best thing is there are no real custom parts. I have an extensive write-up with pictures, parts lists, cost and diagrams atttached. I would be willing to put some kits together if people are willing to reimburse my time and shipping. Maybe $25 bucks (?) above parts and shipping for running around and packaging. My feelings won't be hurt if no one is interested. I'd like to use the $$ to start working on a short shifter solution (at the transaxle, not the lever).

Now to the disclaimer. This mod works great for me. I can't promise it will work for everyone, but I don't see how it could hurt. Easily reversible if so desired. Use at your own risk....affect on warranty unknown....your mileage may vary....CMA...CYA.....

BTW - I see no difference in indicated coolant temperature with or without the bypass

I think we should get a handful of testers (2 or 3) to check their results before we go wild with this mod. I sent Rob a preliminary document and I think he's working on an install now. Hoepfully he'll post results.

To the poster with 226 degrees. That sounds like a problem with your specific car. I've never seen 200 degrees and almost never see 193 (maybe 2 or 3 times in almost 2 years). Check you fluid levels, check for vacuum leaks. Use may want to try some Red Line Water Wetter (I'm a believer).
 

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Discussion Starter · #2 ·
Your sills will still get hot

FYI - the mod cannot prevent your side sills from getting warm.
 

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Discussion Starter · #8 ·
Test Results - GOOD!!

Spent some time today on testing. Results are very good in my opinion (see attachment):) Didn't spend a lot of time prettying up the write up, but forgive me. Content is king anyway!

I've got around 150 miles on the mod, no issues.
 

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Discussion Starter · #9 ·
LW Elise - Condenser Fans?

LW,
Are your fans running when the AC is on? They should be howling like the devil up front.
 

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Discussion Starter · #11 ·
ZTEC

So you're an O-villian or is that O-Villain.....regardless, let's have a beer.:coolnana:
[email protected]
 

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Discussion Starter · #19 · (Edited)
Wow - I appreciate all the great feedback

aw shux! Seriously, thanks for all the kind words. The board kept me going when I was getting worn out with the project a week or so back. It really does motivate you when you get some feedback!!:D

Special thanks to Rob for his help! He gave me some good input and reviewed my ideas and documents.

Looks like Jim-Clayton did some eariler testing on the straight bypass (good job!)with similar results to mine (5-6 degrees difference), so now I have more confidence that this is a common problem. Living in FL is a motivator, isn't it Jim. Also lowering the firewall heat soak is a less obvious, but maybe just as important by-product of the by-pass.

Sounds like there's enough momentum for me to take some names and put together some kits. If your so inclined, send me an email [email protected]. I'll probably collect emails for a few days (say end of the week, 7/29) to get the scope of the number of kits I need to make up, then I'll get back to each of you with the cost and availability date. If I see a number of quick responses, I'll go ahead and start ordering parts to cut down the time lag...please don't leave me hanging!

Two quick comments on recent posts
1) Foam in the sills. I've never really looked at the sills very hard to see the is there is any access, but I do know in Japan some of the Sport Compact guys are injecting their frames with foam for added stiffness. Should make them cooler and quieter too!
2) Bypass in the engine compartment rather than up front to have cooler sills. Likely wouldn't help too much as the main radiator pipes still go from back to front to the radiator. It would also take a larger amount of the available coolant out of circulation. It also bugged me a bit that when the bypass was switched off a fair amount of cooler water would hit the system. But I'm over analyzing....always. It would probably work great.

Again, Thanks for the Thanks!

PS - I guess I hijacked this thread from poll to fix. I get on tangents really easy....as you guys can clearly see.:(
 

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Discussion Starter · #27 ·
About 10 people have already contacted me for kits

I'm surprised, 10 requests in less than 24 hours, kind of a mini-poll of the sorta desperate.....so I'm starting to get parts together for 25 kits. Ordered the bypass valves today. Tripped over to the local electronic surplus outfit to get wire, female connectors for solenoid, heat shrink, and some other hardware. I'm thinking it won't cost more than $95 for the whole shebang including shipping (hopefully closer to $85) . I got a good buy on the valves in quantity that I will pass on in the price. Price will vary on whether you want Redline Water Wetter or not. It would probably be better for me if you just get it locally, it's readily available at most any parts house and totally optional (I use it and like it). Doesn't make sense for me to buy it and have you pay me to ship it to you.

The only open item I know of is the switch in the cockpit. This is very personal on what switch you want and where you mount it. I'm thinking of just taking it off the parts list and deduct $. I will supply the wiring unterminated on the switch end and send along crimp-on connectors so you can "express yourself" through switch choices and mountings. If you don't want to hunt around for a switch and like the mount I did in my car, I can certainly get you that switch. Just let me know in a response to my upcoming email.

Good to hear from Tim M. He's had some good insight earlier in the thread. I latched on to some of his observations.

I will email everyone that's contacted me by Friday with a final price and availability date. I'll ask for a reply with commitment and whether you want Water Wetter and the switch I mentioned above. I'll set up PayPal by then too.

Thanks.
 

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Discussion Starter · #35 · (Edited)
recent posters looking for kits - please send me an email

so I have a clean way to carry on a dialog about the kits.

[email protected]


Thanks! Tony
 

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Discussion Starter · #36 ·
Joetz - 911

Agreed. I had an 83 SC with AC that was just as bad as the Elise. I was always glistening when I arrived at work, or on a date, etc......it was a chick magnet however, so many things were tolerated. I needed all the help I could get.:shrug: Didn't get to really check out the heater much here in central FL.
 

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Discussion Starter · #38 ·
ZTEC - Skycraft...OHYEAH!

That's the "electronic surplus" store I was referring to in previous post. They've even got a website now...
 

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Discussion Starter · #39 ·
I just sent out a kit status to all the folks that I BELEIVE are on the list. If you expected an email, but didn't get one, contact me now.
[email protected]
Thanks, Tony

PS - Rob is installing a bypass this weekend, I look forward to hearing his results.
 

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Discussion Starter · #41 ·
3 hours?

The meat of the project (installing the valve and vacuum switch and bleeding the system) would likely take 1.5 to 2 hours. Plus maybe another hour+ fiddling with switch mount, running wiring, etc. A lot depends on whether you are comfortable enough to dive right in, or are moving cautiously......Once you get the valve in, you can go ahead and drive the car (finish the wiring/switch another time if you need to).

I was hoping to get a timeline when I modify the next car, which looks like it will be this Thursday. I'll post my time then.

Tony
 

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Discussion Starter · #44 ·
qball install

The install went very well and qball is right, we did bs quite a bit. I was also pretty tenative around someone's else's car so that added to the time as well...... but we did get it done with no incidents.:clap: I appreciate him letting me hack around in his car, that was brave (maybe not too bright).

Several updates to the installation procedures were made as a result of the items we ran into. Most notably is we found a much better place to pick up switched 12V power. But first I let qball lay in the passenger footwell upside down trying to sort our wires and fuses 1/2 inch from his face for 20 or 30 minutes. Just as he's gone in for the second dive, I find the switched power in the steering column (super easy access).....

See the picture.....he's much younger than me, so he'll survive. "the good of the many outweigh.......

I look forward to his feedback on the bypass.

I also agree that the Water Wetter keeps my car coolant cooler on average. It's slower to heat up at the lights and comes right back down when I'm moving.

Thanks again qball!

Tony
 

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Discussion Starter · #46 ·
Chuck - not dumb at all

This would be the best way to do it (temp switch position) and I think there is a separate thread going on on the board just for this possiblity. The complicated part (which I think you already understand) is the temp switch does not really have off/on postion (open or closed). Instead it is a potentiometer that varies the voltage over a range and moves a vent door in the climate system that let more or less air flow through the heater core to raise and lower cockpit temperate. 5 volts might mean half open while 11 means completely open and 2 volts means completely closed. It would be a relatively simple electronic circuit to drop the bypass above a certain temp switch voltage (would require a relay), I just got a bit burned out trying to work out he other parts of the kit. Maybe I'll go back and look at it now that the kit seems solid.
Tony
 

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Discussion Starter · #50 ·
recirc works?

Recirc also works? on my car, but it seems the footwell vents are above the passenger's feet....which means the recirculated air is drawn across the extremely hot firewall before it goes back into the climate control system right behind the driver's feet. So in my car the recirc actually performs worse than the fresh air intake to the AC due to the preheating of the air by the firewall....
Tony
 

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Discussion Starter · #51 ·
Lucksta - Blend Door Stepper Motor

Stepper motors do require some smarts as you mentioned. For the actuators I've personally seen (not many), these smarts are in the actuators themselves, not sure where they are in the Loti, but I'm assuming the same.

I know for sure that GM, Ford and Lexus products use a simple potentiometer for controlling the door actuator (some of the education I've gotten during this project). I believe the voltage read at a the various pot positions is sliced into "steps" and the stepper motor is moved in proportion to open and close the blend door. It would be good someone could confirm my assumptions.

I'll look into the one on Otis today or tomorrow.
 

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Discussion Starter · #54 ·
Bypass Switch Answer - Woo-Hoo!!

:nanner2: ET,
I think I've found a good solution for the heater bypass switch that retains the completely stock appearance of the switches (heck it IS stock plus a hidden function). The existing temp control is a 10K linear potentiometer. What I did was just look for a 10K linear pot with an integrated on-off switch. These are plentiful. I saw 200+ today at the local electronics surplus place (Skycraft in Orlando). There are multiple type of shafts, switches, etc. What you're looking for is one that has the on-off with contacts closed at the most counter-clockwise position (coldest setting). What this does is turn on the bypass only when the temp pot is at it's coldest position. As soon as the knob is twisted clockwise (hotter), the bypass is switched out and the heat works just fine. This project does require a bit of soldering and filing, but nothing very fancy at all. NO electronic component work, just unsolder and resolder 3 wires and run two wires to the new switch (which you have to do for the bypass anyway). I actually used a pot with a push-pull switch, so when you want bypass, you just pull it out a bit (til it clicks), when you want heat, push it in and turn up the temp. I think the pot I described at the top is cleaner and more intuitive, I just couldn't find the one I described in the surplus store.

I just installed it today and it's working great. Bone stock look.:coolnana: See pix for details of install. Not too tough at all! Threading the wires through the dash was the most aggravating part....

Specs: 10K linear pot with integrated on/off switch that is normally closed in fully counter-clockwise postiion. 1/4 flat shaft (not just D-shaft, but 1/2 of the material gone from the shaft.
Ah, the end of the road for the bypass design....maybe.
 

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Discussion Starter · #59 ·
Kits available

I think I have enough feedback to let the kits loose on the public. Those of you who have sent me an email should be getting an update now.

Prices are $90 for basic kit, $10 for Temp switch upgrade, 3 for basic switch, $12 for Water Wetter (cheaper if you buy it locally).

If anyone else is interested or didn't receive the update, email me at

[email protected]

I'll be doing 3 more installs on Orlando cars in the next week or two, but I'll be getting out of the install business soon...

New Instructions will be posted in the next day or two.
 

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Discussion Starter · #63 ·
T-65 Freeze up mod

The freeze-up mod repositions the thermostat pickup in the AC evaporator coils. This take about 15 minutes to do and did help my car with the freeze up, but didn't address the poor cooling performance overall. There are other issues that can cause freeze up including wrong freon amounts, poor air circulation, etc.

Hopefully your freeze-up goes away with the mod.

Good luck at that Tampa Bay dealership. I've had issues with their service.
 

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Discussion Starter · #64 ·
JnC - Push/Pull Pot

JnC,
I looked for quite a while trying to find the normally closed switch in the counter-clockwise postion, but no luck. For me this would have been preferable to the push/pull version I was able to find. I'm sure it could be custom made, but at what price and how many. I was hoping by posting the need on the board maybe someone else knew of a source.

FYI - when the switch is "pulled" it only moves out about 3/16 (see pic). So it's not noticeable at all.

Tony
 

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