Nice tidbit for those with barely any heat

[pkattnig]

Note: When you tighten the housing bolts for your thermostat...limit
the tightening to about 150 inch-pounds. I've messed up two housings
before and, since it's getting more difficult to find these parts..use
caution. Also tighten the top, then the bottom, then the top, then the
bottom progressively. I always end up sweating a little when I'm tightening
mine up..don't want to break it again!! Good luck!!

[neanderpaul]

Nice tidbit for those with barely any heat

Note: When you tighten the housing bolts for your thermostat...limit
the tightening to about 150 inch-pounds. I've messed up two housings
before and, since it's getting more difficult to find these parts..use
caution. Also tighten the top, then the bottom, then the top, then the
bottom progressively. I always end up sweating a little when I'm tightening
mine up..don't want to break it again!! Good luck!!

It is not that you overtightened it. The problem comes when the thermostat slips out of the housing as you are trying to install it. The thermostat slips into that tiny gap between the block and the housing and causes the break. The solution is to put one drop of superglue between the thermostat and the housing.

[bravekozak]

Check out this KB Laser cabin heater tap from Australia. It is cable actuated.

[loufestiva66]

my heater fan sometimes comes on and other times it dose not...
what is going on?

[bravekozak]

Someone got that heater tap for 99 cents!

lou, the fan comes on when the fan sensor in the thermostat housing grounds. It is temperature dependent.

[Kbaker2012]

t stat replacement

i have found this very informative.... thanks for the part #'s. what is the best bet for a thermostat housing... yep i broke mine (broke while removing.... bunch of atv or similiar stcky stuff was working too well)...

junk yards are not too great around here in south dakota.... is there an aftermarket housing? (summit has small block chevy housings for 5$).

any replies or private messages are appreciated!
1988 festiva lx carb (silver with red orange and yellow hot rod flames)
g3ride69

you can take the old cracked housing and have it tig welded for around 5 bucks ( I broke mine also)

[lessersivad]

my heater fan sometimes comes on and other times it dose not...
what is going on?

I had the same thing on one of my cars. When the fan wouldn't turn on I would tap the heater box with the side of my right foot and it would kick on.

Did that for a few weeks and finally replaced the blower motor. Has worked fine ever since.

[wirebrain]

I had that problem also...bouncing over some potholes or a railroad track would get it going again....lol I finely took it out and lubed up the bearings with WD40 and that took care of the problem.

[90festivalplus]

Well that explains a lot. I have been fighting the lack of heat issue with mine since the day I bought it. I have gone through 3 stats and they all do the same thing guess the 2 stage will be my next investment

[crazyrog17]

I have the 2 stage and wonder if the smaller of the two thermostats actually decreases cold performance. It opens at a slightly lower temperature (180?) and that's enough to keep the engine under the first white mark on the gauge during the winter. Not until it's 45+ does mine go into normal operating temp range. I'd be curious to try a higher temp two stage stat.

As for the thermostat housings, I found them on fourgreen.com for $8 plus who knows how much for shipping. I'd guess it'd be about $30 total for just the one item.

Link: http://www.fourgreen.com/store/scrip...-p-MB30115172B

[Spike]

My two-stagers from O'Reillys are 195 tstats, I think. I keep about 1/4 inch past the first white mark all winter (although grill is blocked off).

[bravekozak]

How come nobody believes me when I say a two stage thermostat has double the probabilty of failure? A single stage works just as well. That is why 99.9% of all the cars on the road have single stage thermostats.

[Banana Bonanza]

My Festiva lost ability to heat in middle of winter, but I dont drive it much in winter and when did drive it only drove on sunny days so I had solar heated interior. Anyway usual no-heat, temp gauge showing no life, and low fuel mileage. Remembered this thread and read it. Anyway I remember my old 1.3L with the funny thermostat with the two separate valves. I had since went to a low mile Mazda 323 1.6L engine from Japan in Festy. Surprised when I took off thermostat housing, it had single stage stat. The little seal on the stat was ruptured thus it staying open all the time. But until then the single stage stat had let Festy have heat, not lot heat, but heat.

Somebody mentioned one of the autoboned 41492 stats being two stage and fitting Festy engine in this thread. I didnt want pay dealer prices and didnt even want to drive to town just for thermostat, so did search on ebay. Found "CST 41492" on ebay, the pic looking like the stat out of my old 1.3L. Bought it now for $10.25 shipped (the autobone ones go for around $14). Box looked like it had been on some backroom shelf for 25 years but otherwise new. Installed it. Zippity do dah, I have heat and temp gauge goes up into normal range, not far up, but past the lower normal range line like it did when I had the 1.3L engine. However while changing thermostat, plastic end crumbled on fan switch screwed into the thermostat housing (gotta love old plastic...NOT). So have fan going all the time until I get the new switch. Even with fan going all time, the temp gauge still moves up properly (well... properly for a Festiva).

I did read through this long, long thread. Lot theories, but I still dont think anybody has figured out real reason the B3/B6 Mazda engines run cold. Maybe some design bypass or something intended to reduce emissions?? Not size of engine, have driven small engines back when 180F thermostats were the norm and they had plenty of heat.

But since I can get $10 thermostat that lets OEM design system run right and give heat, not going to spend time trying to figure it out to save couple bucks. IMHO, if you can get a Ford or Mazda two stage thermostat for $20-$25, go for it. Otherwise go with the 41492, either genuine CST or one of the mcpart store branded ones that are probably made by CST.

[JohnnyBoy]

July 8,2014 142.jpgJuly 8,2014 141.jpg
Just wanted to show you all a couple of images of what the thermostat should look like. I ordered this thermostat through Mazda for a 91 323. Have a goodie and hope this helps somebody, cured my heat or lack of heat from last winter.

[micro_trucktiva]

Wish I would have found this before I ordered my 160° FAILSAFE thermostat from rockauto.com. do I think I'll have problems with it? No but it good to know for next time.

Anyone by chance have a p/n for the cooling fan switch? My issue isn't heat I have wonderful heat my issue is my fan doesn't turn on and the gauge continues to rise if I let it idle for more than 10 mins or so. While driving it's fine gauge goes up to where I think it should be ( just below the center mark), but if I sit at idle it continues to rise.