Plumbing in your oil stat
Turbo Mini Forums

I have fitted a Mocol oil stat supposedly set to 90 degrees. I also have fitted an oil temp sensor in a sandwich plate between block and oil filter housing.

I have plmbed this in according to the Mocol guide But when I took the car for a quick run tonight I found that the oil temp started to climb past what I believe to be around 125 degrees on the gauge. oil pressure at idle was down to around 30psi water temp was normal.

has anyone else had an issue with one of these? if so how did you resolve it?

Own the day

Looking at the picture it looks like you've connected the hoses in the wrong way. Assuming that the aeroquip hoses are the hoses from the engine block and to the oil filter. If so, they should be connected to the same side of the thermostat (same goes for the oil cooler hoses).

This picture (figure 4 or 5) explains the correct fitment:

http://97.74.103.94/files/thermos$.pdf?Sub...ion+and+Pricing

Edited by MrTurbo on 22nd Jul, 2010.

As above re. flow path being wrong, plus I would not use plain hose and jubilee clips on a 1/2" high pressure oil line.......

Schrödinger's cat - so which one am I ???

ouch. that's definately the wrong way round.

I'm not sure how the bypass system inside the stat works, but you could be at risk of starving the engine of oil by plumbing the stat in wrong!

Mr. Prawn, the friendly Crustacean- slowly making steps towards forced induction.

No. this is the second option they give you to plumb it in derived for BMC front wheel drive cars.

Where as before in fitting instruction 1. As you correctly say the braided hoses in the above picture should be on the same side of the stat body. Thus the oil has to pass over the wax stat in the centre of the assembly.

Configuration 2 allows for the above pipe routing, again the oils has to flow over the wax stat.

By touch both the braided hoses very hot which means the wax stat was being bathed in hot oil the temp gauge was around 125 degrees C the inferred temperature gauge confirmed this.

I split the oil stat removed the wax stat and placed in a jug of boiling water, Nothing, no movement at all. I then utalised the heat gun and finally got it to open.

Thinking that it must just have been stuck due to it being new I went back to the boilng water only to see it close.

The wax stat fitted to this assembly was supposed to open at 80 degrees. I phoned Mocol with the numbers and had a little rant as without the benefit of a gauge I would have cooked my engine they have agreed to take it back to see what the issue is

Edited by Mr Joshua on 23rd Jul, 2010.

Own the day

Mr Joshua,

I went through the thermostat description again and made a drawing of your set up, I have to agree you are absolutely right (should have made the drawing before my first answer..)

Good to hear you've found the cause!