Fail Safe vs Regular Thermostats

[stat1K]

well normal thermos don't stick open unless they are a failsafe... they stick closed. every vehicle i have ever owned has overheated once (i live in arizona) and everytime it has it was because of the thermostat sticking closed so i got sick of it and whenever i replace it or get it replaced i only use failsafe ones. haven't had a problem from the thermostat since.

[HostileJava]

well normal thermos don't stick open unless they are a failsafe... they stick closed.

I'm sure that's not true. The factory service manual even details how to test your thermostat to see if it's getting stuck open or shut. I think I'm just going to stick with the Honda OEM gasket and thermostat

[Oldblueaccord]

Is it an Astro type van GM 4.3? our gets worse gas milage as it cold. I have a hard time keeping the temps up over 180. I could do it with some cardboard but the wife drives it and I dont know if she would realize its overheating and take the cardboard out.

Ours is a 99 astro awd we get about 15-16 and maybe 18 on a highway trip.

wp

[HostileJava]

Is it an Astro type van GM 4.3? our gets worse gas milage as it cold. I have a hard time keeping the temps up over 180. I could do it with some cardboard but the wife drives it and I dont know if she would realize its overheating and take the cardboard out.
Ours is a 99 astro awd we get about 15-16 and maybe 18 on a highway trip.
wp

No it's a 98 Odyssey, has the same motor as the 6th gen 4cyl accords. I would imagine the coolant temp thing works the same way, as the engine warms up it reduces the gas being injected in.

[Blkblurr]

well normal thermos don't stick open unless they are a failsafe... they stick closed. every vehicle i have ever owned has overheated once (i live in arizona) and everytime it has it was because of the thermostat sticking closed so i got sick of it and whenever i replace it or get it replaced i only use failsafe ones. haven't had a problem from the thermostat since.

The original honda thermostat in my car failed in the open position. What happens is the mechanisn that opens and closes the thermostat valve comes apart and no longer moves the valve seat. It fails in what ever position it was in when it came apart.

[Blkblurr]

There is a time stamp problem with this board. I just posted a reply to someone in this thread nd it didn't show up at the bottom. the last post on this thread now is time stamped as today at 11:40 PM It is currently 4:24 PM EST

[Oldblueaccord]

This isn't exactly related to the 3g since I'm replacing it in my van, but I was just wondering if any of you had experience with the fail safe thermostats and if they really are safer or if they just cause more problems. The van has been getting crappier gas mileage as it gets colder out and I've noticed that it barely gets warm, so I'm assuming the thermostat is stuck open and that because of that it's using more fuel cause it's running colder.

I really had not ever heard of them actually sounds like more or less somekinda marketing bs. I never have had one fail closed myself now i have had them fail partially open or the spring gets weak and the water flow will force it open when running.

As far as my wifes POS GM van yeah it must run a little richer. I misread your sig and thought the van was a GM sorry.

wp

[2oodoor]

There is a time stamp problem with this board. I just posted a reply to someone in this thread nd it didn't show up at the bottom. the last post on this thread now is time stamped as today at 11:40 PM It is currently 4:24 PM EST

Same problem here folks, time is done gone wierd today....
the astro van wont get but 19 mpg on the hwy, at best unless your by yourself and have no load you may get 22mpg.

As for fail safe thermstats, someone showed me what they do, they very carefully drill a 1/8 hole on the side of the thermostat. you have to be very careful not to distort the unit at a whole because it is an instrument, a semi delicate ;piece. so if you drill it , do not bend or squeeze, .If I was to do it I would have a dang sharp bit to start with and wear mechanix gloves and hold it in my hand to drill it with variiable speed cordless drill. you still get thermo control but if it ever gets stuck closed it passes enough to overheat real bad.

[HostileJava]

This isn't exactly related to the 3g since I'm replacing it in my van, but I was just wondering if any of you had experience with the fail safe thermostats and if they really are safer or if they just cause more problems. The van has been getting crappier gas mileage as it gets colder out and I've noticed that it barely gets warm, so I'm assuming the thermostat is stuck open and that because of that it's using more fuel cause it's running colder.

[shepherd79]

james, the best thing you can do, get honda thermostat. about month ago i replaced mine and my car warms up a lot faster and it stays warmer a lot longer.
fail safe thermostat works very well.

[HondaBoy]

well i've bought a few Fail Safe's and kept having to replace them every few months because they'd get stuck open. left the car running too cold, bad fuel mileage and wasnt a good thing. so nah, dont even bother with one. i dunno why they never worked in my car. other people here had said they experienced the same thing.

[stat1K]

if the failsafe thermostat you're using continues to open and stay open then there is more than likely a problem with overheating in your engine... i've never had one stick open for no reason, unless the thermostat you bought was in the wrong temperature range and kept thinking your car was overheating. i would always get a failsafe on hte off chance your car does begin to overheat the failsafe will stay open as normal thermostats spring closed.

[HostileJava]

if the failsafe thermostat you're using continues to open and stay open then there is more than likely a problem with overheating in your engine... i've never had one stick open for no reason, unless the thermostat you bought was in the wrong temperature range and kept thinking your car was overheating. i would always get a failsafe on hte off chance your car does begin to overheat the failsafe will stay open as normal thermostats spring closed.

I don't have a failsafe one in there now, as far as I know it's the original thermostat that's in there, or are you talking to HondaBoy? However my van runs way colder then my wifes and the gas mileage has gone down as it gets colder, so I'm assuming it's cause my thermostat is stuck open.

[HondaBoy]

my car runs cold to begin with. i stuck a stock type in there and havent had to replace it for over a year or so. i havent had a problem with my car over heating though, only running too damn cold. but now runs great and is a daily driver. never gets hot in the summer either.

[alboy86]

hmmm im debateing on which to get fail safe or OEM the one i got in mine is the original and it works good it has over heated once for no reason but i was driving it down to SD from SF and it over heated in LA but it over heated after i started it and stoped the engine in a short time so maybe it closed up but anyways i might go with fail safe i would rather have it over cool the engine then have it over heat and kill it

[VTEC_Inside]

I've only experimented with a failsafe one once, on another car. I'll never buy on again. POS failed/ locked open within a week.

Nothing but OEM thermostats in any of my Honda vehicles.

I've replaced both my Accords and my gfs Integras within the last year. The Accord wouldn't get up to full running temp until I got onto the highway. The Integra would cool down at stop lights and be back up to temp as you got moving.

In both those cases the springs of the old ones were significantly weaker than the new replacements.

[RamThis]

I've had one go on my Integra that way. Stuck wide open and the car would never warm up. Also happens that at the same time the top of the radiator split open. So, it got a new radiator and a new thermostat at the same time. After that all was fine and dandy! Until my radiator split again a few months ago. Now it has a new all metal Modine radiator, new thermostat (for good measure) and ALL New coolant hoses (wont take any chances after losing the 3G to a damn coolant hose!!)

And this time stamp thing is getting annoying LOL.

[Hash_man_Se_i]

Fail safes are garbage. I remember when I worked at partsource, we had so many people bringing them back cuz they failed so quickly we pretty much just never sold them to anyone, but we had to stock them still.

[2oodoor]

Ok lets not let this thread die cause of the time stamp, it is interesting and alot of us are having similar issues.
what I am deducting here is the oem dealership thermostat is the best one to get despite any mods etc..
And, HostileJava, my personal take on you plea for assistance on another Honda is just fine to me. I dont have a problem with it at all, in fact, since the forum was consolidated of 1,2,and 3 generation accords, why not invite odessey entheusists. It is almost an accord, and sure beats the daylights outta argueing about toyotas on the forum, yes?
I dig your vans, shoot. so which stat are you going to use. my D15 civic is doing that stone cold guage reading then it goes to normal , then stone cold, it makes me nervous. I am in the process of slowley desludging the engine. I have oem pvc valve ordered from honda dealer, I will get oem thermostat if that is the best one. my pvc was completley stopped up, and the engine smoked pretty bad when I hit it hard, with only 120K something has happened , hopefully jiffy lube dint get a hold of it... I am using castrol 5w30w, like the manual says, you may want to check that on yours, the later engines want the 5w20 or 30 esp for cold weather. it will give you better mpg...anyway I also added a can of RESTORE in case the cyls got jiffy lubed lol , Im gonna change it every three weeks for a while and BG clean the intake, the car runs too good to have major issues, but the smoke is not a good selling point. I used a regular thermostat in the accord and it seems to be working fine.

[HostileJava]

Well it sounds like I"ll be stopping by the local honda dealership then. If the OEM thermostat held up this long I guess there is no real reason to switch now

[mailman37645]

As far as fail safe thermos go, once you install them and after your car heats up they open and stay open. They will not close again. What happens then? Your computer tells the engine that it is running cold all the time and keeps dumping in fuel to the cold engine, therefore, wasting gas and making a mess of your valves to boot. Of course with most all engines having alunimum heads it is normally bad if your car overheats. I run OEM thermos in all three of my hondas, two accords and one civic.

[HostileJava]

As far as fail safe thermos go, once you install them and after your car heats up they open and stay open. They will not close again.

Ummmm............................no. This is a quote direct from MotoRad's website:

"Unlike standard thermostats, the Motorad Fail-Safe® thermostat, is built with an extra stroke that automatically locks into an open position when an overheating condition occurs. This allows the coolant to continue to flow between the radiator and engine, thereby protecting the engine components from serious damage while the vehicle is safely driven to the nearest service centre."

Meaning it opens further and locks into place if the coolant becomes to hot, it will not lock and stay open under normal driving conditions. What would be the point of even having a thermostat if that was the case?

Oh, and in case anyone is wondering, I got the OEM thermostat and within about 5 minutes it's heated up, even on these last few mornings when it's been about 5-10 degrees out.

[HondaBoy]

so i'm still stumped on why me and quite a few members here have used the fail safe T stat and after some use they end up staying open, consistantly even with decent running engines? i replaced my T stat yesterday along with my radiator, got an OEM type.

[MessyHonda]

i paid like 10.88 for mine from honda...solved my problem