Cruising Vs Stationary Water Temp Readings (Pics)

[Ams 23 1 Cars]

I carried out a coolant change recently and changed the standard 1Bar GTi6 radiator cap to a 1.3Bar item from Halfrauds. I was hoping it would make a difference but it really hasn't. The following pic is the vehicle up to operating temp and occurs when I'm driving steady at say 30mph and above. It pretty much stays at this point:

 

 

When I park up it'll creep slowly up to the mark below, this is exactly the point upon which the second fan activates:

 

 

 

When the second fan is blowing the temp needle drops extremely slowly, in fact it'll drop back a smudge to the second last white marker and stop blowing, only to start up again shortly after as the needle once again reaches the above point. Is this typical? I'm not losing coolant and the car drives fine. I'm aware the gauge overreads but it's butt clenchingly worrying to see a temp gauge read so high and stay in that zone until I get properly moving again.

 

Not a very good pic (was checking battery clamps) but shows a bit of the plumbing, there's a T-Piece below the expansion tank. I'll try and dig out a better pic of the pipework if it helps. :

 

 

 

If there's something not right I'd love to know.

[dcc 855]

These readings are pretty much a guess to be honest. But from your 2nd picture thats where my old 1.9 8v would sit. Sandy had my old gti on the roller and the temp was sat at roughly 90, but thats with a shorter, all be it fatter rad.

 

One thing I will say is these engines (XU10J4RS) do run far hotter than a 205 as standard. They run a higher water cooling pressure too, from what I can gather it will help compensate poor cooling in these engines.

 

In short, the temps dont look too bad, I possibly would look at a coolant flush and maybe check the radiator for blockages (if you're feeling flush - maybe a new radiator? )

[TooMany2cvs 65]

You mentioned the second-speed fan. But no mention of the first-speed fan. Is that switching on?

[jackherer 543]

As above, sounds like the low speed resistor is disconnected.

[welshpug 1,657]

I'd get a lower temp fan switch personally, as the standard XU10 thermostat is 83 degrees, so one increment lower than the original will work fine, search on the forum for "intermotor" and you'll find one or two recent threads with all the info.

[Ams 23 1 Cars]

The radiator and heater matrix are new and I carried out a flush when I changed the coolant recently. It has never overheated and is slow to creep up to the second fan activation point but when it does the fan cannot/does not reduce the temp much at all, I have to get moving to make that properly happen. The previous owner stated:

 

 

The twin fan has been adapted to fit the 205. In warm temp or after high speed the high speed fan (2^nd stage) will cut in as it should at just over 90 degrees.

 

I'll visually check whats going on with the fans. I presumed the first fan is always on at a steady rate but inaudible due to engine noise so I should really check it's actually on! I'll definitely look into the lower temp fan switch using the search term mentioned, sounds like the right thing to implement. Cheers for the pointers!

Edited August 1, 2013 by Ams

[welshpug 1,657]

they might have been wired in incorrectly which would bring them on in series not parallel, which would slow them down.

[TooMany2cvs 65]

is slow to creep up to the second fan activation point but when it does the fan cannot/does not reduce the temp much at all

Because it hits the high-speed cut-out temp, at which point you SHOULD be going to low speed fan to continue to drop the temp.

 

There's a brand spankin' two-speed fan switch in the glovebox of the VW camper at the mo.

<goes and checks>

Marked on it is "95-85, 102-92".

 

That means that when the coolant hits 95degC, the low speed fan cuts in. If it continues to rise, the high speed cuts in at 102. As it cools, the high speed cuts out at 92, then the low speed at 85. If it's just high speed working, then you'll have no fan below 92 - which is too high. You should have the fan on until the coolant's down to 85.

 

The actual numbers may be different, but the concept will still apply to ANY two-speed fan switch. You need to figure out if your low speed's working, and if not why not. Unless, of course, the previous owner's actually got it all set up as just a single speed. In which case, it sounds like too high a fan switch temp range.

Edited August 1, 2013 by TooMany2cvs

[MikeC 10]

Get a multimeter and check the resistor. Was bending welshpugs ear the other day abut these switches (cheers mei) got a switch and it ended up being the resistor.

Would a lower temp switch be better for 205/309/306?

[petert 586]

What are these "resistors" you speak of?

 

I've only had experience with A/C cars which have a two speed/two fan system. The two fans are either in series or parallel, depending on how they are switched by a set of 3 relays. Series is the slow speed. If one fan was faulty, then neither would turn on until the high temp setting was reached, when they'd be connected in parallel.

[welshpug 1,657]

Single fan, two speed, no relays, one resistor similar to the dim dip system.

 

None of this heavy twin fan ac business!

[Anthony 1,003]

The non-AC system is completely different Peter.

 

It doesn't use any relays and runs full current through the fan thermoswitch. On the slow speed setting, it runs the current through a large resistor that's clipped to the top of the radiator, thus slowing the fan, and on fast speed it runs direct to the fan, thus running the fan at full speed. There is only a single fan, although some people graft in a 2nd fan using the same wiring.

[chipstick 382 1 Cars]

Mine will get to the first line you show in your original picture and then when the fan kicks in it prevents it going much further than that.

 

One thing I have noticed of late is how many people comment on the loudness of my fan. I haven't had the car get to the higher line, so always assume the speed mine kicks in at is the low speed, but is there a chance due to a fault with the resistor than mine perhaps kicks in fast at the lower speed point?

[jackherer 543]

I've never heard of a resistor failing short circuit but if you replace the low speed resistor with a direct wire it will behave like that.

[Miles 331 1 Cars]

They can be plugged in the wrong way which means they do not work, I tend just to wire them up so it's high speed all the time, Some Base models are like this and it reduces the amount of wires you have

[Ams 23 1 Cars]

I went out and checked today and I think what's happening is pretty much what 2cvs and others have suggested. The cowling fitted to the radiator is for two fans but since it's so obscured I assumed there actually was two fans in there, unfortunately when I inspected closer by peering through the grill there is only one fan! Furthermore it seems this fan does not activate at all until the temp rises to the level indicated in Pic.2!

 

 

Because it hits the high-speed cut-out temp, at which point you SHOULD be going to low speed fan to continue to drop the temp.

There's a brand spankin' two-speed fan switch in the glovebox of the VW camper at the mo.
<goes and checks>
Marked on it is "95-85, 102-92".

That means that when the coolant hits 95degC, the low speed fan cuts in. If it continues to rise, the high speed cuts in at 102. As it cools, the high speed cuts out at 92, then the low speed at 85. If it's just high speed working, then you'll have no fan below 92 - which is too high. You should have the fan on until the coolant's down to 85.
The actual numbers may be different, but the concept will still apply to ANY two-speed fan switch. You need to figure out if your low speed's working, and if not why not. Unless, of course, the previous owner's actually got it all set up as just a single speed. In which case, it sounds like too high a fan switch temp range.

 

 

Yup it appears the fan only has one speed and the previous owner has set it like this , once the needle is in the "oh sh*t" zone it audibly buzzes/whooshes away - it doesn't lower the temp by much, it really just stops it from rising. Bear in mind this high temp issue only occurs at sub 20mph speeds and when stationary, once I'm rolling 30mph and above the temp drops and remains at the level shown in Pic.1.

 

Does this look like a wiring issue or would I need a lower temp fan switch as well?

Edited August 2, 2013 by Ams

[welshpug 1,657]

you should find a 5 pin brown plug with three wires which is the test point, one pin will be permanently live, the other two are the low speed and high speed wires, get a piece of wire and bridge from the live to either of the pins and note what the fan does.

 

 

if nothing happens when you bridge one but it does come on full on the other pin look for the resistor, or the brown 3 pin plug to it (with only two wires) remove the resistor is present and make up an insulated wire to bridge the pins, your fan will now come on full speed at the lower temperature.

[Ams 23 1 Cars]

Will do cheers Welshpug! The car is parked in another location so I'll do this tomorrow when I'm back round there, so just to make sure is the 5 pin brown plug in this box by any chance? It seems to be where the radiator related electrical gubbins resides:

 

Edited August 2, 2013 by Ams

[Paul_13 212 1 Cars]

It won't be in that box mate but will be in that area.

Trace the wiring loom back from the rad switch.

 

If definitely get a lower temp fan switch!

[Tom Fenton 1,541]

Alter the wiring back to the way Peugeot intended with both slow and fast speed working and your issue will go away.

[Ams 23 1 Cars]

Think I may have found the issue, but first here's the radiator switch below. Don't know if it's a standard item:

 

And here's the issue I'm not sure of, the brown plug below was hiding under the washer screen container...is that terminal meant to have a resistor attached? There were no other radiator related bits I could see that looked out of place apart from that.

 

Edited August 7, 2013 by Ams

[DanteICE 72]

yeah I think that's the resistor plug. Why would some turd remove the resistor?

 

 

Testing/working with the fan system

 

The link above (half way down) is my post about testing and fixing the fan system; might help you out. You could probably short out the plug with a bit of wire and see if the fan comes on at both full speed and half speed positions, by shorting out either the tester plug or the actual thermoswitch plug.

 

Geoff

[Ams 23 1 Cars]

I actually have that thread saved already, pretty handy:) Yup I'm definitely missing the resistor! Thing is I'm not sure what type of resistor I should have... 306 GTi6 or 205 GTi?

[Anthony 1,003]

205, as that's part of the original car rather than something transplanted from the 306/Xsara donor

 

If you're not fussed about the fan being two speed, you can just short those two wires on the brown 3 pin plug together, which will make the fan come on high speed straight away

[welshpug 1,657]

205, 306 doesn't use one unless its a rallye, but the cooling system is totally separate on a 205.

 

I have a few spares