Attention MK1 Owners - Check your Thermostat!

[welshrussell]

Just thought I better share this with other Forum Members

After seeing comments by MadMark and Baconsdozen I found out a truly startling fact.

It seems the modern thermostats I've been buying for my V4 2litre Essex have not had a hole in them to prevent air locks

In the past my engine has just got hotter and hotter till it redlines and then dumps it's radiator contents all over the floor

So today, I whipped out the thermostat and drilled a 4mm hole through it, so hopefully now letting steam to escape.

Here is a photo of the thermostat in place with it's new hole:


It's MOT time tomorrow morning so I will see how the van goes then (and if my blue gasket glue-ing techniques were any good)

Mark and Kevin - please add to this, correct me if I have worded this wrong or forgotten anything important.

[madmark]

russ well done my frend!
this is very important to essex v4 owners who replace there thermost, QH for some reason list a thermostat without the bleed hole for the essex v4 this is very important ,i nealry lost my brand new engine rebuild because of this! i would go off up the road then all of a suden it would overheat and dump all the rad contents out all over the floor !
if it wasnt for the fact of BD pointing this out to me i would of never of guesed it was something so simple!

so if you do have a v4 and you have fitted a new stat then for god sake check it has the bleed hole to stop the airlocking!

[baconsdozen]

Hello Mark and Russell,I wonder if such a daft thing is what started all the stories about v4s overheating.As we've found out the lack of a bleed hole can cause then to boil over and yet I've not seen it mentioned anywhere else .Maybe the poor old v4 got a reputation for something that wasn't really its fault.

[j6393]

Hello Mark and Russell,I wonder if such a daft thing is what started all the stories about v4s overheating.As we've found out the lack of a bleed hole can cause then to boil over and yet I've not seen it mentioned anywhere else .Maybe the poor old v4 got a reputation for something that wasn't really its fault.

I agree. When I bought my first V4 Transit everyone told me that they overheated and as summer temperatures here usually exceed mid-40C's I have always kept the radiator serviced regularly but I also use an early opening Holden thermostat (same part no. as the Transit) which has a bleed hole as standard.
Even on the hottest days my Transits have never boiled.

[baconsdozen]

The old type thermostats used to have a small hole drilled throughb them and a little pin fitted in them that was free to move about and by doing so kept the hole clear of rust and scale.The pins were called jiggle pins and were one of the favourites items (along with sky hooks and long weights) to send an apprentice off to the store room for as a practical joke.

[welshrussell]

Hello Mark and Russell,I wonder if such a daft thing is what started all the stories about v4s overheating.As we've found out the lack of a bleed hole can cause then to boil over and yet I've not seen it mentioned anywhere else .Maybe the poor old v4 got a reputation for something that wasn't really its fault.

I agree. When I bought my first V4 Transit everyone told me that they overheated and as summer temperatures here usually exceed mid-40C's I have always kept the radiator serviced regularly but I also use an early opening Holden thermostat (same part no. as the Transit) which has a bleed hole as standard.
Even on the hottest days my Transits have never boiled.

I think I'll look into these 'Holden' types and see if they are still available - if they are the right ones for my engine

[j6393]

Holdens are really an Aussie icon as one of the biggest sellers in Australia and there are still plenty of the old straight sixes around so it is still easy to buy aftermarket stuff in Australia.
However I doubt that you would be able to buy parts for them easily in UK but the size of the Transit thermostat seems to be a common one so it is just a matter of finding the right heat range for the opening temperature.

[welshrussell]

Holdens are really an Aussie icon as one of the biggest sellers in Australia and there are still plenty of the old straight sixes around so it is still easy to buy aftermarket stuff in Australia.
However I doubt that you would be able to buy parts for them easily in UK but the size of the Transit thermostat seems to be a common one so it is just a matter of finding the right heat range for the opening temperature.

Cheers for this - I managed to find one after all on ebay, it comes with the hole and has a operating temp of 73c (if I remember right)

[baconsdozen]

I had thought of going on ebay and selling just the holes for the thermostats.All you'd need is a 2mm drill to fit them.50p a box of two.

[welshrussell]

I had thought of going on ebay and selling just the holes for the thermostats.All you'd need is a 2mm drill to fit them.50p a box of two.

I like that a lot

[madmark]

I had thought of going on ebay and selling just the holes for the thermostats.All you'd need is a 2mm drill to fit them.50p a box of two.

[welshrussell]

Just thought I'd show people what the original thermostat should look like



Sorry for the picture quality but I hope you can see the little plastic ball hanging down from a hole in the thermostat rim. It is held in place with what looks like a small piece of wishbone shaped metal.

[baconsdozen]

You can't beat holding your balls in place with a piece of wishbone shaped metal.

[welshrussell]

You can't beat holding your balls in place with a piece of wishbone shaped metal.

[fremsley]

Hi all,

I drilled out my hole in the thermostat and i thought all was going well. however on a 40 odd mile run to tthe south coast meet she behgan to overheat right up to the line (45-50 mph). On the way back she went into the red. Hoiwever, there was still coolant on the rad when she cooled down. I've just started her up today and there is some water coming out of the exhaust (enought to wet my hand in a few seconds). So do we think its the head gasket? Any advice appreciated.

cheers

simon