P38A Thermostat Housing seal on a diesel

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EntropyUK

Well-Known Member

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467

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Hemel Hempsted

• Feb 9, 2018

• #1

Should the thermostat housing have some form of seal around it. I took mine off and couldn't see one but thought that plastic to metal would require some form of seal or gasket. I looked in Rave but that only referred to just the thermostat seal?

Also are there any point to note on fitting the thermostat to ensure a correct and water tight fit?

 

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Ratae

Well-Known Member

Posts

3,278

• Feb 9, 2018

• #2

LRcat shows a large 'O'-ring STC2194.
http://new.lrcat.com/#!/1234/90127/90128/7157/90552

I don't know if the stat has a specific orientation but if it has a jiggle pin/air bleed hole then I'd put it at the 12 o'clock position. Perhaps RAVE has the info.

The Classic V8 stat must be fitted with the jiggle pin/air bleed hole at the 12 o'clock position or trapped air can't pass stopping water getting to it & the stat will stay closed.

 

Last edited: Feb 9, 2018

Grrrrrr

Technician, Bodgit & Scarper Ltd

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19,898

Location

Buckinghamshire, UK. ('95 DT)

• Feb 9, 2018

• #3

Pretty certain there's an o-ring on mine. I thought it only went 1 way up as well but been a long while since I had mine out. That's marriage for you ...

 

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EntropyUK

Well-Known Member

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467

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Hemel Hempsted

• Feb 9, 2018

• #4

I managed to get the thermostat off. Looks like the o ring sits around the inner side of the housing and is clamped tight. It did look as if the thermostat had been sealed into place as it didn't want to come out at all. I can see that it could be a problem if the thermostat does seat exactly.

 

Last edited: Feb 9, 2018

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EntropyUK

Well-Known Member

Posts

467

Location

Hemel Hempsted

• Feb 10, 2018

• #5

Quick one for all. What's the view of applying a bead of gasket sealant between the thermostat and the engine block. I think this was the cause of the original leak.

 

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Ratae

Well-Known Member

Posts

3,278

• Feb 10, 2018

• #6

Possibly done by the PO to try & stop the leak.
Wonder if they'd tried to re-use the O-ring which is usually a mistake as they deform & harden in use so often won't seal again.

 

wammers

No longer with us, RIP

Donater

Posts

58,170

Location

Preston Lancs.

• Feb 10, 2018

• #7

EntropyUK said:

Quick one for all. What's the view of applying a bead of gasket sealant between the thermostat and the engine block. I think this was the cause of the original leak.

Click to expand...

Just fit a new Oring with a hint of Hylomar. Ensure housing is flat.

 

Last edited: Feb 10, 2018