Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Kate on 19 March 2016, 17:12:03

Title: Thermostat and Water Pump on a 2.5 Diesel
Post by: Kate on 19 March 2016, 17:12:03
Hi all. :y

Sorry to be a nuisance with all my questions. I know I'm a pest. ;D

I'm going to have a go at changing the thermostat and water pump on my overheating diesel. I've read the guide for the water pump but I can't find a guide for the thermostat. Is there a Haynes manual that would cover this job? I've looked at lots of manuals for sale online but none seem to cover the 2.5 diesel engine.

Thanks for all the help! :y
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: zirk on 19 March 2016, 17:16:23
Not for the Omega, if you need a Manual best bet is for an older BMW 325, 525 etc with the same lump 2.5TD.

Not sure if this will help you -

http://images.omegaowners.com/documents/25TD/M51D25_Engine.pdf
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: tunnie on 19 March 2016, 17:51:24
I thought a mobile mechanic diagnosed a HG failure?  :-\
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Kate on 19 March 2016, 18:06:31
I thought a mobile mechanic diagnosed a HG failure?  :-\

He did but I wanted to be certain, one way or the other.
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Kate on 19 March 2016, 18:08:47
Not for the Omega, if you need a Manual best bet is for an older BMW 325, 525 etc with the same lump 2.5TD.

Not sure if this will help you -

http://images.omegaowners.com/documents/25TD/M51D25_Engine.pdf

Thanks very much, that's very helpful. :y
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: tunnie on 19 March 2016, 23:02:07
I thought a mobile mechanic diagnosed a HG failure?  :-\

He did but I wanted to be certain, one way or the other.

A compression test would be a better approach.  :y
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Mr.OmegaMan on 23 March 2016, 20:39:26
Spotted this genuine Vauxhall 2.5TD water pump going pretty cheap.

https://www.ebay.co.uk/ulk/itm/152023490089
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Nick W on 23 March 2016, 20:53:10
Spotted this genuine Vauxhall 2.5TD water pump going pretty cheap.

https://www.ebay.co.uk/ulk/itm/152023490089 (https://www.ebay.co.uk/ulk/itm/152023490089)


Did you notice the plastic impeller? Metal ones are less problematic
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Mr.OmegaMan on 23 March 2016, 21:08:33
Spotted this genuine Vauxhall 2.5TD water pump going pretty cheap.

https://www.ebay.co.uk/ulk/itm/152023490089 (https://www.ebay.co.uk/ulk/itm/152023490089)


Did you notice the plastic impeller? Metal ones are less problematic

I did but though't I'd share either way. I am aware metal impellers are the preferred choice given the option. Anyway...
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Kate on 23 March 2016, 23:25:36
Thanks but I ordered one yesterday. :y

http://www.ebay.co.uk/itm/291291304987?_trksid=p2057872.m2749.l2648&ssPageName=STRK%3AMEBIDX%3AIT (http://www.ebay.co.uk/itm/291291304987?_trksid=p2057872.m2749.l2648&ssPageName=STRK%3AMEBIDX%3AIT)
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: TheBoy on 24 March 2016, 18:06:32
Stat dead easy when doing pump - basically disconnect hose, unbolt housing, replace stat.

Hardest bit of whole pump/stat job is removing the viscous fan, which can be a bugger.
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Nick W on 24 March 2016, 19:08:23
Stat dead easy when doing pump - basically disconnect hose, unbolt housing, replace stat.

Hardest bit of whole pump/stat job is removing the viscous fan, which can be a bugger.


You loosen it as soon as you have room to get a fan spanner on it, by giving that a bash with a proper hammer. As long as you've checked which hand the thread is , it isn't a difficult job.
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: TheBoy on 24 March 2016, 19:16:58
Stat dead easy when doing pump - basically disconnect hose, unbolt housing, replace stat.

Hardest bit of whole pump/stat job is removing the viscous fan, which can be a bugger.


You loosen it as soon as you have room to get a fan spanner on it, by giving that a bash with a proper hammer. As long as you've checked which hand the thread is , it isn't a difficult job.
Oh, believe me, if only ze germans had made it that easy. idiotting it rarely works, which I guess is why BMW/LR/GM specify a pulley lock to counterhold before said idiotting.

Like many (stupid, poxy) viscous fans, its LH thread on the TD lump, for reference.
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Kate on 24 March 2016, 19:24:40
The fan is missing so I didn't need to remove it.
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Bigron on 24 March 2016, 20:08:35
I had to remove the vicious (deliberate typo!) fan many times due to overheating problems, so when you get a fan to put on, Kate, it WILL be a left-hand thread, because it helps it to tighten as the engine rotates - otherwise it could spin off in service.
Should you need to remove it at a later date, a tip from a garage man in Cornwall - take a beefy screwdriver with a pound-through handle, hold the blade firmly against a corner of the fan's retaining nut at its RH edge, and give the handle end of the screwdriver a firm and sharp tap with a grown-up hammer!

Ron.
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Nick W on 24 March 2016, 20:11:18
Stat dead easy when doing pump - basically disconnect hose, unbolt housing, replace stat.

Hardest bit of whole pump/stat job is removing the viscous fan, which can be a bugger.


You loosen it as soon as you have room to get a fan spanner on it, by giving that a bash with a proper hammer. As long as you've checked which hand the thread is , it isn't a difficult job.
Oh, believe me, if only ze germans had made it that easy. idiotting it rarely works, which I guess is why BMW/LR/GM specify a pulley lock to counterhold before said idiotting.

Like many (stupid, poxy) viscous fans, its LH thread on the TD lump, for reference.


I realise you've probably never heard this before, but you're not hitting it hard enough ;D  It's like breaking tapers loose, a hard, sharp impact is required.
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Shackeng on 24 March 2016, 22:35:30
In the first few years I owned my TD, I left the fan in place, but when it needed to come off, I never had a problem, just a sharp tap on the large open ended adjustable while holding the fan.
Kate, the stat is dead easy as described above, with the added bonus of no 'B' bolt! I replaced my pump with a metal impeller about 10 years ago, and have had no problems since. :y
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Kate on 24 March 2016, 22:57:54
I've done the stat already, just waiting for the water pump off ebay then I'll fit that.

Should I try and get a fan or will it be okay without one?
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: relluf on 24 March 2016, 23:09:02
I've done the stat already, just waiting for the water pump off ebay then I'll fit that.

Should I try and get a fan or will it be okay without one quote]




Kate leave it off !!
If you really want one its in my shed I will send it to you but you really don't need it.
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Kate on 24 March 2016, 23:17:42
I've done the stat already, just waiting for the water pump off ebay then I'll fit that.

Should I try and get a fan or will it be okay without one quote]




Kate leave it off !!
If you really want one its in my shed I will send it to you but you really don't need it.

Thanks Andy, I'll leave it off then. :y
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: TheBoy on 25 March 2016, 12:00:24
In the UK, the viscous isn't needed. Actually, it does more good to leave it off.
Title: Re: Thermostat and Water Pump on a 2.5 Diesel
Post by: Kate on 25 March 2016, 20:30:07
In the UK, the viscous isn't needed. Actually, it does more good to leave it off.

Great, one less job to do then. :y