Technical where is the thermostat?
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Technical where is the thermostat?
I don't know on the diesel engine, but try following the top hose of the radiator to the engine block. The radiator pipe should fit to a bolt on housing, and inside this housing should be the thermostat.
I'm not 100% sure, but it's worth a look.
Chas
I'm not 100% sure, but it's worth a look.
Chas
Thermostat ! I wonder why u r looking for it. I can tell you exactly where it is but its a non-serviceable part. It either works or u gotta replace it. My understanding is that u r looking for the electrical thermostat that turns on the radiator fans? or Perhaps u mean the heat valve whose purpose is to quickly bring the engine to working temperature. In a diesel i'll tell u where both are located. Simply follow the upper radiator hose tht goes from the radiator (right next to the battery) all the way back towards the twin diesel pumps and ends in a junction of radiator hoses. The heat valve in diesel is placed in that junction and the whole thing needs to be replaced if its faulty. Also on the side of the junction ull notice a plastic plug with wire coming outaa of it. That the thermostat for electric fans.
I hope the above is useful!
Rgds.
Omer
I hope the above is useful!
Rgds.
Omer
thanks so much for the reply guys. my uno is overheating, the mechanic removed the housing where the thermostat should be but what we only saw was a rusted makeshift thermostat!(4 washers in a bolt) thats why the water is not flowing anymore. my mechanic told me that we dont need a thermostat in our country because its hot here, and he just removed the makeshift thermostat for the water to flow through. but temperature is not like before which is only 1/4 of the temp gauge, now it still reaches half of the gauge. i dont know what causes this anymore, here's what i've done so far to my uno, maybe someone can help me out.
1. replaced timing belt and valves, valve clearance: all .3mm or .012inch
2. replaced head gasket
3. radiator cleaned
4. removed makeshift thermostat
i was just thinking what is the purpose of the thermostat? will removing it change the water flow?
1. replaced timing belt and valves, valve clearance: all .3mm or .012inch
2. replaced head gasket
3. radiator cleaned
4. removed makeshift thermostat
i was just thinking what is the purpose of the thermostat? will removing it change the water flow?
The thermostat is there for a reason to regulate the engines temperate, stays closed when cold to warm the engine faster and opens when hot to release the coolant flow and maintain a steady temp. I would have thought the thermostat is a good idea regardless of climate but I guess I can see what your mechanic guy is suggesting by leaving it always open, better than always closed would have thought.
Could it be that your radiator is blocked or that the radiator fan is not coming on as temperatures rise. When does it overheat?
Could it be that your radiator is blocked or that the radiator fan is not coming on as temperatures rise. When does it overheat?
bigmac said:
Often, yes.
I haven't seen the thermostat on your engine. But in many cases it is known as a 'bypass' type - as the valve opens, the back part of the plate closes a bypass passage in the housing. The purpose of this bypass passage is to allow coolant to circulate around the engine when the thermostat is closed.
The problem is that with the thermostat removed, neither the radiator nor the bypass passage are blocked off... so the coolant takes the easy path, 'bypassing' through the engine and not flowing through the radiator. Hence the possible overheating with thermostat removed.
I would suggest fitting a thermostat, even for hot climates, as it does ensure that the engine runs at a consistent temperature (allowing 'reserve' capacity for heavy-load periods). If you absolutely must leave it out, study the housing to see if you can identify the bypass passage that I'm talking about, and block it off with a shaped piece of wood or similar. Make sure that coolant flows only from the cylinder head to the radiator, and from the radiator to the water pump. Depending on design, it may not be possible to block off the bypass without affecting the heater, etc. But I'm guessing that perhaps you don't use the heater?
-Alex
thanks guys, im not using the heaters because its already hot here. my uno overheats when im going 80-100kph, reaching half of the gauge(which i didn't experienced before). i had it checked again and the mechanic noticed that theres a leak in the water pump and when we turned on the engine, we heard noise from the water pump. my mechanic said that the bearing might be broken, another cause of overheating. fiat here says that waterpumps are sealed, i have to replace the whole thing which costs quite high. has anyone tried to repair their waterpump? and how do i remove the waterpump?
Pretty common failure, the water pump, especially if the cooling system has been run on plain water (tends to happen in countries where 'antifreeze' is not required!) You should always put in the 'green stuff' as I call it 
I think, to replace the water pump bearing, you will need a strong press. I'm also not sure whether the pump has one long bearing or two 'normal' bearings, because I don't know if the pump is the same as the other Uno engines.
Generally the trend is towards replacing the pump complete, as this replaces the bearings and the seals at the same time. You only need the front part of the pump (front plate with impeller, shaft, and pulley) and not the housing that is bolted to the engine block. The price of this should be moderate - on our market, NZ$70-$100 (35-40 pounds equivalent) which, with it costing NZ$60 to fill the fuel tank, I'd consider to be an OK-price
Cheers,
-Alex
I think, to replace the water pump bearing, you will need a strong press. I'm also not sure whether the pump has one long bearing or two 'normal' bearings, because I don't know if the pump is the same as the other Uno engines.
Generally the trend is towards replacing the pump complete, as this replaces the bearings and the seals at the same time. You only need the front part of the pump (front plate with impeller, shaft, and pulley) and not the housing that is bolted to the engine block. The price of this should be moderate - on our market, NZ$70-$100 (35-40 pounds equivalent) which, with it costing NZ$60 to fill the fuel tank, I'd consider to be an OK-price
Cheers,
-Alex
:worship: AlexGs !
Do as he says Big Mac. Fiat Diesel's water pump has a single bearing. Make sure u use a new gasket when u fit the new pump and add the recommended green stuff . The more the better!
On 2nd thot also make sure that cooling fans on the radiator work when the temp rises. Sometimes a blown fuse or faulty relay cause the engine temp to rise since radiator doesnt loose sufficient heat. but at high speeds.. ummmh. sufficient air is already passing thru the radiator. are u sure temp rises only at high speeds?. my diesel uno actually cools down when driven at high speeds... 80 Kmh +
Rgds.
Omer
Do as he says Big Mac. Fiat Diesel's water pump has a single bearing. Make sure u use a new gasket when u fit the new pump and add the recommended green stuff
. The more the better!On 2nd thot also make sure that cooling fans on the radiator work when the temp rises. Sometimes a blown fuse or faulty relay cause the engine temp to rise since radiator doesnt loose sufficient heat. but at high speeds.. ummmh. sufficient air is already passing thru the radiator. are u sure temp rises only at high speeds?. my diesel uno actually cools down when driven at high speeds... 80 Kmh +
Rgds.
Omer
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thanks guys. yup, temperature rises only at hight speeds. i checked my thermostat housing and i saw 3 big tubes, 2 of them connects to the radiator and 1 comes from the water pump. alex said that i need to block one? ill try to figure out the water flow direction and ill inform you guys as soon as possible.
