Thermostat change without doing timing belt?

[crazyazz]

Hi guys,

My thermostat must be stuck open as my car is running cold, taking ages to heat up and dropping temp with the heater on etc.

Is it possible to change it without doing the timing belt? This was done about 8000km ago and I dont want to do it again for a thermostat.

Any suggestions would be greatly appreciated

[erykv1]

you will have to remove the belt to get to the waterpump. you dont have to replace the belt if you think its still good.

[getslideways]

This is why its best to take care of those hard to get to items when doing the timing belt, such as the thermostat and water pump. Otherwise, you'll be doing it twice.

Now if you did, and your new thermostat failed within 8K km then that is some crummy luck.

[crazyazz]

Thanks for the reply, by waterpump you mean thermostat housing? The service book has timing belt and waterpump replaced, but not thermostat. Of course at the time Im sure it wasn't an issue

[crazyazz]

This is why its best to take care of those hard to get to items when doing the timing belt, such as the thermostat and water pump. Otherwise, you'll be doing it twice.

Now if you did, and your new thermostat failed within 8K km then that is some crummy luck.

Yes it sucks, it was before I bought the car. I would have done it as a preventative measure for sure

[Taloras]

Yes it sucks, it was before I bought the car. I would have done it as a preventative measure for sure

Compare the path of the timing belt below



with the location of the thermostat and water pump, below (centered)



They're UNDER the belt. Simultaneous replacement is advised because there's no extra work involved, given you already have to take the timing belt off to get at the thermostat and water pump.

Also, our cars have a plastic thermostat housing that doesn't last more than a few years. It's HIGHLY recommended to replace it while the thermostat is out, either with a brand-new plastic one or one of the aluminum ones.

[crazyazz]

Compare the path of the timing belt below



with the location of the thermostat and water pump, below (centered)



They're UNDER the belt. Simultaneous replacement is advised because there's no extra work involved, given you already have to take the timing belt off to get at the thermostat and water pump.

Also, our cars have a plastic thermostat housing that doesn't last more than a few years. It's HIGHLY recommended to replace it while the thermostat is out, either with a brand-new plastic one or one of the aluminum ones.

Thanks mate, I will source an aluminum unit. So I will also need the locking bar if I take the belt off correct?

Also no possible way to half remove the belt and slip the housing out and back in I take it?

[Taloras]

Thanks mate, I will source an aluminum unit. So I will also need the locking bar if I take the belt off correct?

Also no possible way to half remove the belt and slip the housing out and back in I take it?

I mean, you COULD, but considering you'll have to take the thing off anyway and you can get a Continental belt for $30 http://www.rmeuropean.com/Part-Numbe..._1FAEF62B.aspx, you might as well. Really. Seriously. Do it. For the 6-8 hours to take things apart this much and put it back together again, do it.

You don't NEED the bar, but it's a pain to do it without. I think you can rent it for like $40 from JHM or somewhere.

[crazyazz]

I mean, you COULD, but considering you'll have to take the thing off anyway and you can get a Continental belt for $30 http://www.rmeuropean.com/Part-Numbe..._1FAEF62B.aspx, you might as well. Really. Seriously. Do it. For the 6-8 hours to take things apart this much and put it back together again, do it.

You don't NEED the bar, but it's a pain to do it without. I think you can rent it for like $40 from JHM or somewhere.

thanks for the info, so I dont need a new tensioner etc?

[erykv1]

if youre confident with the parts used on the last timing belt change, you can reuse them. you can definitely time the engine without the bar, but its useful to have for sure. You can always mark the pulleys once they are at TDC with a paint marker.

[MacDaddy]

I did, its completely doable.

crank the engine over by hand while pulling the belt towards you, it will shift about half way off the sprokets, giving you enough room to remove the thermostat housing.

have fun :)

[crazyazz]

I did, its completely doable.

crank the engine over by hand while pulling the belt towards you, it will shift about half way off the sprokets, giving you enough room to remove the thermostat housing.

have fun :)

Excellent, thanks man

[Monty23]

Also, our cars have a plastic thermostat housing that doesn't last more than a few years. It's HIGHLY recommended to replace it while the thermostat is out, either with a brand-new plastic one or one of the aluminum ones.

My original plastic thermostat housing has been fine now for 105K. I have heard of people "upgrading" to the metal version, but I rarely hear people complaining about the plastic housing being an issue.

[BlkBullitt]

I did, its completely doable.

crank the engine over by hand while pulling the belt towards you, it will shift about half way off the sprokets, giving you enough room to remove the thermostat housing.

have fun :)

+1, I've done this as well. It's somewhat of a pain to get the housing in/out, but is very doable.

[rdcyclist]

My original plastic thermostat housing has been fine now for 105K. I have heard of people "upgrading" to the metal version, but I rarely hear people complaining about the plastic housing being an issue.

I've had two plastic housings fail or I guess you could say wear out. I would never do a timing belt job and leave a plastic housing in there no matter the mileage. It's too much of a pain in the ass to replace for the hunnert buck savings.

[Taloras]

I've had two plastic housings fail or I guess you could say wear out. I would never do a timing belt job and leave a plastic housing in there no matter the mileage. It's too much of a pain in the ass to replace for the hunnert buck savings.

Mine was in pretty poor shape when it came out @110k, probably because the PO appears to have sacrificed his soul to the devil (mixed coolants). Even if you're not gonna spend $150 for an aluminum one, at least get a new plastic one for $50.

ECS has a nice kit with t-stat, housing, and o-ring for $65. http://www.ecstuning.com/ES2771457/

[crazyazz]

When did the metal housing appear? My car is a 2000 Euro spec as Im from Australia, could I already have the metal unit?

[MacDaddy]

i do't think the B5 S4 ever had a plastic thermostat housing.

mine is a 2000 (sept 1999 build) and its metal.

[Mike@PureMS]

The plastic housings often time get corroded and start crumbling causing leaks. We're seeing it more and more now that the cars are starting to age. I'd definitely look into a minimum of replacing it with a new plastic one, or the metal one.

Metal Thermostat Housing

[crazyazz]

Forgot to update the thread :P I was able to change the thermostat by cranking the engine with one hand and pulling on the timing belt with the other, I removed it enough to slide the housing past to get at the thermostat



While I had the front in the service position I replaced my poor looking serpentine belt and installed an apikol snub mount

[rtl5009]

What a pain in the ass.

[slow ride]

And what a stupid place to put a thermostat haha

[crazyazz]

I reckon , it was a pain in the ass at least I did the snub and serpentine belt to make it more worth while

[pilla]

Thanks for the confirmation this can be done without removing the timing belt and thanks for the picture. Im going to attempt a t stat change myself now.

[m_haiser]

totally possible, did it on a 2.8 without removing the timing belt

[landfill]

There is no point in doing one
without the other unless you
did it yourself recently or have
service records it was done recently.

If you have to a leaking water pump
or thermostat you replace the timing
belt and ancillaries. If you’re doing the
belt and ancillaries you also do the water
pump and thermostat.

I rarely make exceptions to that rule.

[neilthewheel]

I reckon , it was a pain in the ass at least I did the snub and serpentine belt to make it more worth while

Lol, Im the same way. I dont put that much work into something just to get back to square 1

Tried to adjust the shocks (raise the car) for a long trip to Toronto, but the collars were seized.
I even took them out so I could better get medieval on them and they wouldnt budge.
I was so pissed off at that point, after all that work and getting nowhere, that I ended up with fancy motor, trans, and rear end mounts, and a turbo back.
No fkn way Im putting in that much work and coming out even, or empty handed

[pilla]

There is no point in doing one
without the other unless you
did it yourself recently or have
service records it was done recently.

If you have to a leaking water pump
or thermostat you replace the timing
belt and ancillaries. If you’re doing the
belt and ancillaries you also do the water
pump and thermostat.

I rarely make exceptions to that rule.

My timing belt was done about 10k ago and they did not do the t-stat while they were in there, (previous owner) or if they did, its failed. But pulling the pipes and front end off to gain access to the timing belt area is an easy enough job i suppose.