Thinking this needs replacement

MSiege

Patience is a virtue
Working on my cooling system and decided that the failing hose connections and corrosion around the thermostat housing were signs of age and wear. Looking at the pictures, what do you all think! LOL!! I'm thinking this part may have never been removed before.

I do have a real question, though... Inside the housing there is nothing (last picture). Isn't there supposed to be a thermostat? Why would there be nothing?

Thanks for your thoughts and advice.
 

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I am pretty sure I see the thermostat in the fifth picture, but it is kinda dark, so maybe not. That part is the thermostat housing, you have to split it to get to the thermostat itself.
 
Pretty sure there's no thermostat, but maybe the bypass hole has been blocked off so there's only flow via the radiator - difficult to see, but yeah 😮
 
Working on my cooling system and decided that the failing hose connections and corrosion around the thermostat housing were signs of age and wear. Looking at the pictures, what do you all think! LOL!! I'm thinking this part may have never been removed before.

I do have a real question, though... Inside the housing there is nothing (last picture). Isn't there supposed to be a thermostat? Why would there be nothing?

Thanks for your thoughts and advice.
This part (its actually 3 parts, the water outlet, the thermostat and the thermostat manifold) needs hours of restoration. While you are at it, check the crossover pipe from the waterpump for internal corrosion and all the water pipes in the central tunnel. A lot of these cars were parked in the day when the 'professional mechanic' attended to one thing (like a sticking thermostat) and did not bother to check and repair the rest of the system. To do it right probably costs $1500 in parts alone these days. When done right, the car runs cool and does not blow headgaskets.
 

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Pretty sure there's no thermostat, but maybe the bypass hole has been blocked off so there's only flow via the radiator - difficult to see, but yeah 😮
OK, I was definitely looking at it wrong. I thought it had not been split in all the pictures, picture 5 has the t-stat cover off. (I think)

No t-stat is a personal choice, but there is definitely something else not right about that unit. I went out to the garage and grabbed a carb version that was laying there. I guess picture 5 from @MSiege is looking at what should be the hole the thermostat opens and closes.
I stuck a little flashlight in there to try to show the passages.
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Some of the pics in post #1 have the T-stat cover on, and others have it off. I don't see a T-stat in there.

When a old car has cooling issues, some owners think removing the T-stat will solve the problem. Obviously it won't.

I'd definitely look for a replacement housing assembly. There is a LOT of missing alloy on those large hose fittings, typical of systems that weren't serviced. Which means there's likely to be a lot of other corrosion and damage elsewhere throughout the cooling system, like @johnph said.
 
Thanks everyone. Restoration of this unit seems like a real stretch. Pretty much all of the metal in the fittings is shot. Two of three thermostat cover bolt heads sheared off. Frankly, I feel lucky that the engine mounting bolts came out cleanly. Will look for a refurbed version. Just missed one by a couple of days on MWB…
 
Thanks everyone. Restoration of this unit seems like a real stretch. Pretty much all of the metal in the fittings is shot. Two of three thermostat cover bolt heads sheared off. Frankly, I feel lucky that the engine mounting bolts came out cleanly. Will look for a refurbed version. Just missed one by a couple of days on MWB…
You can get new or used ones. Midwest Bayless has used ones. Eurosport in the UK has brand new ones for carb or FI.

The thermostat on these cars does more than thermostats do on most other cars. I couldn’t imagine not using one in the system.
 
I'm pretty sure that these are specific to the X1/9 (in that I think the stat housings on 128s and the related SOHC Yugo models are not considered EZ fit substitutes), and the fact that they came in two flavors originally (FI and non-FI version) makes good used FI versions pretty thin on the ground. Luckily for those who are in need, Eurosport UK has had a run of reproduction stat housings made.
 
That looks like a thermostat housing for a carburettor car to me, I dont see the thermo switch screwed into the housing. The new parts are frightfully expensive, you'd be best asking in the FS&W section if anyone has a good used housing, and yes definitely put a new thermostat into it.Maybe JimD will sell you the one he has that's "just laying about"

Also be sure to use the correct gasket between the housing and the head, one that fully separates the EGR passage in the head from the cooling system... the gasket you need is the one to the right... it's a trap for young players.

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SteveC
 
That looks like a thermostat housing for a carburettor car to me, I dont see the thermo switch screwed into the housing. The new parts are frightfully expensive, you'd be best asking in the FS&W section if anyone has a good used housing, and yes definitely put a new thermostat into it.Maybe JimD will sell you the one he has that's "just laying about"

Also be sure to use the correct gasket between the housing and the head, one that fully separates the EGR passage in the head from the cooling system... the gasket you need is the one to the right... it's a trap for young players.

View attachment 73943

SteveC
They are expensive but at least they are available.
 
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well for that price I'm sure many people would hunt for a good used one... and even consider using one with "not quite" the right steel fittings and getting "creative" with routing water to the inlet manifold / water heated choke, which after-all is the main difference between all the models... you could use an EFI thermo housing with relative ease, and for a chunk less $$'s

348gbp is over $650aud plus freight and import taxes... thats frightfully expensive in my book.

There was a guy in Italy and another in Spain that were selling new reproductions online before eurosport were, and with 160,000 examples of the X19 made I'm sure there are quite a few good used units out there if you look.

SteveC
 
348gbp is over $650aud plus freight and import taxes
Just had a look back at this and the price is 290 GBP ex tax: the 348 includes UK tax (VAT) @ 20% which we have to pay over here. IIRC there's no equivalent tax on imports of this amount into the US, but yeah, Australia will add 10%, although no extra duty as it's under the threshold I believe.

In Europe, we do get the rough end of taxes (even without Brexit), as all imports (including those from Australia!) attract tax (which can range from 18% to 27% depending on country) and there's a relatively low duty threshold too :(
 
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My car is a carb'ed 1300 with a/c. The Eurosport UK replacement (see below) has neither the dead-end bore in my original housing or the extra hole over it, in the correct gasket pictured above. Why was there a dead end bore originally? Seems like the Eurosport version eliminates the boring and uses a solid gasket across the entire mating surface.
 

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My car is a carb'ed 1300 with a/c. The Eurosport UK replacement (see below) has neither the dead-end bore in my original housing or the extra hole over it, in the correct gasket pictured above. Why was there a dead end bore originally? Seems like the Eurosport version eliminates the boring and uses a solid gasket across the entire mating surface.
if the thermo housing has that hole or not is of no consequence, likewise if the gasket has the hole or not is of no consequence... what does matter is that the coolant passage and the EGR passage don't intersect by using the incorrect gasket that will allow them to, otherwise lots of head scratching will ensue.

another member on here recently went thru this and thought he'd made a mistake somewhere along the line when doing a cylinder head overhaul ... I picked it and noticed it in his FB post , alerted him that he likely had the wrong gasket fitted, before he pulled the head again! replacing the gasket with the correct one was a lot easier than pulling the head again.

SteveC
 
My car is a carb'ed 1300 with a/c. The Eurosport UK replacement (see below) has neither the dead-end bore in my original housing or the extra hole over it, in the correct gasket pictured above. Why was there a dead end bore originally? Seems like the Eurosport version eliminates the boring and uses a solid gasket across the entire mating surface.
Are you referring to the dead end bore for the air injection? That was only used on the 1500 head. The 1300 used an external manifold and no bore in the head for air injection. When using the 1500 head, it is important to use the correct housing and gasket to block the end of the bore to keep exhaust gates out of the coolant.
 
Some 1300's in North America must have the EGR passage thru the head, elanplus2 has a 1978 1300 and he's the one who had the wrong gasket fitted first time around... so it's not just the 1500 head.

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Yes, mine is a 1977 1300 and I definitely have this same EGR passage. Thanks for the caution to make sure it's covered/blocked correctly...
 
Some 1300's in North America must have the EGR passage thru the head, elanplus2 has a 1978 1300 and he's the one who had the wrong gasket fitted first time around... so it's not just the 1500 head.
That is interesting if the external manifold was not used on some 1300s. The 1974 - 1978 US factory service manual only shows the external manifold. Is it possible that the 1300 heads may have been replaced somewhere along the line? Were there any other countries besides the US that required air injection while the 1300 was being produced? If so, perhaps they went with the internal bore as it is a much better design than the external manifold if you need air injection. If the internal bore US 1300 head really existed, it is surprising that they did not switch all later 1300 cars to it as it saves a number of parts and the labor to install them. Those external manifolds also had a habit of melting plastic fuel filters (mounted on the firewall right next to the air injection manifold) when someone would do a half assed desmog and just disconnect the air pump belt. This would allow exhaust gas to get the manifold really hot (also not very good for the air pump). I saw two cars like that and I think the only reason they did not go up in flames was that the flow of gasoline was probably keeping the plastic just cool enough not to melt completely through.
 
That is interesting if the external manifold was not used on some 1300s. The 1974 - 1978 US factory service manual only shows the external manifold. Is it possible that the 1300 heads may have been replaced somewhere along the line? Were there any other countries besides the US that required air injection while the 1300 was being produced? If so, perhaps they went with the internal bore as it is a much better design than the external manifold if you need air injection. If the internal bore US 1300 head really existed, it is surprising that they did not switch all later 1300 cars to it as it saves a number of parts and the labor to install them. Those external manifolds also had a habit of melting plastic fuel filters (mounted on the firewall right next to the air injection manifold) when someone would do a half assed desmog and just disconnect the air pump belt. This would allow exhaust gas to get the manifold really hot (also not very good for the air pump). I saw two cars like that and I think the only reason they did not go up in flames was that the flow of gasoline was probably keeping the plastic just cool enough not to melt completely through.
I've said it before, but I'm no full bottle on the various emissions change over dates on USA spec cars, but the head in question had a 1977 manufacture date cast into it.. the thread is here ...somewhere elanplus2 posted a picture of his reconditioned head and it sure looks like a plain 1300 head to me. Now with a sample size of two it would seem that the USA spec air injection system went away from the external four branch manifold and the passage was internal for later engines.

SteveC
 
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