Notices
General Miata Chat A place to talk about anything Miata

Quick question about coolant temps. and the t-stat...

Old Dec 14, 2009 | 04:20 AM
  #21  
OZMX-5's Avatar
Junior Member
 
Joined: Apr 2008
Posts: 46
Total Cats: 0
Default

Originally Posted by Doppelgänger
I can only think of two things.. airbubble in the system...or...I managed to put the t-stat in backwards. If it's air, it should burp it out in a few warm up/cool down cycles.

Thoughts?
why not 3rd factor... that the re-route is working very effectively?
Perhaps TOO effective, as too cold can have an adverse effect on engine longevity.

After I installed mine, I logged many different types of runs on my MegaSquirt, and I had the same results as you.
On one cold morning (approx 15-18 degree celcius), cruising down the highway for about 10minutes, I saw my needle drop to less than 1/3 position.
But once the speed slowed and we started driving around suburban streets, it slowly rose back up to around 10'o-clock position, then settle to a little less than the usual 11'o-clock.

Nothing much to worry about in my opinion, but if runnig too cold is a concern, then do what I do and install a protective, but still free-flowing, grille during winter to impede air-flow a little.
Old Dec 14, 2009 | 09:23 AM
  #22  
Doppelgänger's Avatar
Thread Starter
Elite Member
iTrader: (12)
 
Joined: Sep 2007
Posts: 6,850
Total Cats: 71
From: Charlotte, NC
Default

Originally Posted by saboteur
How did you ground it? A wire with two ring terminals or something? I'll be having the same problem...
Yeah..kinda. Took a 6" piece of wire and two ring terminals. I took one end and opened it up (the ring now represents/looks a locking washer) and kinda wedged it in bewteen the bolt and the spacer...and the other end of the wire is grounded via bolt to the head. Make sense?



Originally Posted by OZMX-5
why not 3rd factor... that the re-route is working very effectively?
Perhaps TOO effective, as too cold can have an adverse effect on engine longevity.

After I installed mine, I logged many different types of runs on my MegaSquirt, and I had the same results as you.
On one cold morning (approx 15-18 degree celcius), cruising down the highway for about 10minutes, I saw my needle drop to less than 1/3 position.
But once the speed slowed and we started driving around suburban streets, it slowly rose back up to around 10'o-clock position, then settle to a little less than the usual 11'o-clock.

Nothing much to worry about in my opinion, but if runnig too cold is a concern, then do what I do and install a protective, but still free-flowing, grille during winter to impede air-flow a little.

See above reply to why my needle was all over the place. The spacer was insulating the ground for the temp sensor. I don't know if this is an issue for 90-93 or 94-97....but for 99-05 you will need to add a ground from the spacer to the head.
Old Dec 14, 2009 | 09:50 AM
  #23  
hustler's Avatar
Tour de Franzia
iTrader: (6)
 
Joined: Jun 2006
Posts: 29,085
Total Cats: 375
From: Republic of Dallas
Default

Originally Posted by Doppelgänger
See above reply to why my needle was all over the place. The spacer was insulating the ground for the temp sensor. I don't know if this is an issue for 90-93 or 94-97....but for 99-05 you will need to add a ground from the spacer to the head.
oh snapes.
Old Dec 14, 2009 | 10:54 AM
  #24  
thymer's Avatar
Senior Member
iTrader: (5)
 
Joined: Apr 2008
Posts: 822
Total Cats: -2
From: VA
Default

Originally Posted by Doppelgänger
Ah ha! Voctory is mine!

Even after I rewired the extension and made sure all wires connections were nice and tight, I was still having the issue..although the needle spent less time on "C". So thismorning before I left work, I had idea. I thought about how the spacer is now sandwiched between two gaskets..which act as insulators and maybe the sensor needs a ground. I mean, in stock forum the bolts holding the neck to the head act as grounds and with the spacer the bolts don't. So after grounding the spacer to the head, the temp. gauge worked perfectly normal on my way to work today. Finally. I win.
Awesome call-out and makes complete sense. I'm getting ready to do the same thing and will make sure to add a ground.
Old Dec 14, 2009 | 05:11 PM
  #25  
timk's Avatar
Senior Member
 
Joined: Dec 2004
Posts: 1,278
Total Cats: 37
From: Brisbane, Australia
Default

Yeah nice work on the findings! I'll cheat and find a ring terminal I can fit over the thread of the temp sensor, then ground that.

Makes me wonder how many people are thinking "holy **** batman, this coolant reroute is winner!" when in fact they've just broken their gauge.

OZMX-5 - Have a think about it; your car won't do that if you have a working thermostat.
Old Dec 14, 2009 | 10:07 PM
  #26  
therieldeal's Avatar
Senior Member
iTrader: (2)
 
Joined: Oct 2007
Posts: 547
Total Cats: 2
From: Northeastern CT
Default

Originally Posted by OZMX-5
why not 3rd factor... that the re-route is working very effectively?
Perhaps TOO effective, as too cold can have an adverse effect on engine longevity.

After I installed mine, I logged many different types of runs on my MegaSquirt, and I had the same results as you.
On one cold morning (approx 15-18 degree celcius), cruising down the highway for about 10minutes, I saw my needle drop to less than 1/3 position.
But once the speed slowed and we started driving around suburban streets, it slowly rose back up to around 10'o-clock position, then settle to a little less than the usual 11'o-clock.

Nothing much to worry about in my opinion, but if runnig too cold is a concern, then do what I do and install a protective, but still free-flowing, grille during winter to impede air-flow a little.
if a properly done reroute is causing "over cooling" and affecting engine longevity, plz explain the several 200k mile escort GT engine's i've had...


.... yeah.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Rick02R
WTB
3
Jan 3, 2016 07:18 PM
slomiata
MEGAsquirt
5
Oct 7, 2015 01:11 PM
tazswing
Race Prep
20
Oct 3, 2015 11:04 AM
shooterschmidty
Engine Performance
8
Sep 30, 2015 10:28 PM


Thread Tools
Search this Thread

All times are GMT -4. The time now is 08:47 AM.