Alfa Romeo Owners Club of Australia Forum

Technical => 160 Series (90, 75, 164 Sedans) => Topic started by: Alfamania on April 30, 2014, 02:03:41 PM

Title: which v6 thermostat??
Post by: Alfamania on April 30, 2014, 02:03:41 PM
G'day,

Im getting mixed signals regarding thermostats for the Alfa 75 v6 3 litre. Some thermostats come by themselves and some recommend getting it with the housing. Can I replace the thermostat by itself and keep my housing? I saw some high flow thermostats which claim 30% extra flow thinking this could be good for the summer, here is a link for them on ebay:

http://www.ebay.com.au/itm/141031114297?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

Any suggestions/advice?

Thank you
Title: Re: which v6 thermostat??
Post by: Cool Jesus on April 30, 2014, 02:51:53 PM
If there's no issue with the housing, the thermostat just pops out. It's held in under spring load, just push down on the tangs past the housing arms and turn it. I too was confuzled till I tried it with my 164.
Title: Re: which v6 thermostat??
Post by: colcol on April 30, 2014, 04:43:42 PM
The 'high flow' thermostats need to be looked at with a bit of caution, as the coolant needs to only flow so fast or slow, as it has to absorb heat from the engine and then give up the heat to the radiator, if it is flowing to fast, the heat exchange won't be happening as well as it should be, i am sure Alfa Romeo engineers have worked out how fast the coolant has to flow, Colin.
Title: Re: which v6 thermostat??
Post by: Domenic on May 01, 2014, 08:19:35 AM
Hey

Don't want to put you off, but you'll be wasting you time and money on the thermostat you posted the link to. It won't fit, plain and simple without modifying the housing.

The thermostats from Alfa came complete with the housing. It makes me laugh every time i see a listing on the internet of a simple drop in thermostat for a V6 12v Alfa engine.
You can "make" it fit, but you'll need to get someone with tools to machine the housing (which will cost you money).
Secondly, people have used 164 thermostats on 75 and GTV6's in the past when the original ones weren't available. The problem with that is you need to cut the upper radiator hose as the 164 outlet is on the passenger side, whereas the 75 is on the drivers side.

Again there isn't a point in buying a 164 thermostat as you can now buy the correct thermostat for the 75 or GTV6 and not worry about cutting up the top radiator hose.

So i guess the easiest way if you need to replace your thermostat is get the correct one for your 75 as like i said they are available and you don't need to "modify" anything. Simply unbolt the old one and bolt in the new one. Also as Col mentioned, the Alfa engineers knew what they were doing, even back then. That's why the outlet of the thermostat is on the drivers side, so the hose has a bit of give in it as the engine moves, whereas it won't if you use the 164 one.

Title: Re: which v6 thermostat??
Post by: Cool Jesus on May 01, 2014, 02:58:08 PM
Oh poo, so Dom your saying it's the complete housing that needs replacing? Not just the thermostat mechanism if it's faulty.

Ps, should have made it clearer. I was only talking of the mechanism. Housing are different, EW v NS engine orientation etc.
Title: Re: which v6 thermostat??
Post by: Domenic on May 01, 2014, 04:20:56 PM

Hey John,

Apologies if it wasn't too clear.
The V6 thermostat is a complete thermostat element and housing. It does separate, but you won't find a drop in element that fits.

You'll need to find someone that can machine the housing out to accept a drop in thermostat element. We both know when you have to pay someone for their time machining something it becomes an expensive exercise.

Hope that clears it up a bit. As mentioned before, for the price of a drop in element then finding someone to machine the housing without breaking it, you'll save time and money buying the complete housing and using the correct part for the car.
Title: Re: which v6 thermostat??
Post by: Meng on May 07, 2014, 11:41:19 AM
http://www.ebspares.co.uk/alfa75/engine30v6.cfm
Title: Re: which v6 thermostat??
Post by: Alfamania on May 09, 2014, 07:43:00 AM
i should also mention that the thermostat housing on my 3.0 v6 says Savara Torino...are these original from factory? if so, it means that there is no way i still have the original thermostat in there....i can only assume that someone has put a drop in thermostat in there? just a thought...
Title: Re: which v6 thermostat??
Post by: ARQ164 Shane on January 03, 2015, 11:47:47 PM
hi guys
does any one know what temp the thermostat open at on the 164 or a 2.5lt 75
I'm only asking because the one in the 164 is made of steel and the 75 one is made from brass.

cheers Shane