I am an owner since 1999 of an Alfa Romeo 145 Junior edition 16V 1.4 T.S (AR 33503) model year 1998 Gama version (930).
All this years engine temperature despite driving and weather conditions was always just a click below 90C, right in the middle of the temperature instrument.
Unfortunately in 2016 and without any previous visible signs, engine got overheated. Most probably because of poor engine gasket seal maintenance (it should have been replaced in the long term routine maintenance).
Engine repair cost required was higher then replacing it with a used one. And so it happened. Engine changed with used same type which was in pretty good condition. All other motor peripherals were maintained from the first one except few that had to be replaced with new ones. Some with original parts and others with after market parts (such as sparks, thermostat, water pump, temperature sender, MAF, Cam belt, etc...). Only the radiator was substituted with a used one, original part number, thoroughly cleaned and maintained.
However, from the first few rides it was obvious that unfortunately the car did not resemble to its previous condition. Poor performance, many technical issues and of course, temperature issues arise.
The mechanic responsible for the refit, on the one hand, claimed that most likely the engine was an earlier version than the original thus working on slightly higher temperature levels, and on the other, that the oil that passed through in the water system during the overheating, was preventing the coolant system to operate optimally and that after some time the system would clean it self gradually returning to its standards. Back then it sounded somehow a logical explanation and just rested upon it... big mistake. Just 10 moths later this engine got also overheated with out even a warning light blink!
This time went of course to a different mechanic, just to someone, not a fancy specialized guy but an "old guard" brought up from the good old days. Thankfully the engine this time didn't suffer from serious irreversible damage so it went for a repair. Most of the motor peripherals were also replaced for the second time. During the repairs, it came out that we also had to replace the intake manifold which we did. So, and having in mind to improve somehow performance, without any fitting problems, installed a manifold from a 2.0 liter AR 156 TS!
This time finally, the result of the repairs and the refit was on its whole ...magnificent! The 19 year old car reminded its brand new days, not to mention that in some aspects it even performed better!
But one thing persisted. Temperature issue was once again present! Just that this time it seems to be somehow better regulated. It fluctuates around 90C reaching up to 100-110C in traffic and goes as low as 80C in open highways. All cooling system parts checked thoroughly twice this time and most of them replaced with new ones. But problem still persisted.
Just a few days ago the temperature metering instrument malfunctioned. So i got another one. A used one, as new ones are not anymore available. Installed it and was terrified to see that the temperature problem was even worse than i thought. What was going on? ... i knew that the new instrument i got was from an AR 146 TS 2000 model, the MY version. Just to notice that the two reading instruments looked in first sight the same but actually weren't. The original had 90C in the middle between 50C lower and 130 higher, while the other had 80C in the middle between 40C in the low end and 120C in the top end!
However readings corresponded actually to the same values in both instruments. It's just what looked like nominal in the original one around 90C, in the other looked as if it was way above the middle nominal temperature area. When temperature rise up to 100C in the first one, in the other seemed to be very high, almost overheated! ...puzzling !
So does that mean that different engines from different production years, models and versions have different spectrum of working temperatures? And beyond that, is matching the right parts to the actual corresponding version a bit more complex than it seems? For example i have noticed that there are two diversions of thermostats. Some of theme start to circulate when reaching 88C while others do that quite lower in 82C! Both diversions, even after checking parts with VIN number, are supported for all TS engines! And that is even more puzzling...
So now what, anybody any ideas? Thanx!
old versions of TS engines (metal top) work at around 80 ºC, while newer versions (plastic top) my 98(not sure) and after work at about 90 ºC.
there are two versions of temp gauge dashboards, earlier with an 80 at the middle and newer with the a 90 at the middle. it happens that in the earlier dashes looks like the 80 (and 40 and 120) were misprinted and actually indicate 90 ºC (50ºC and 130ºC). so, if in an older version gauge points to «80 ºC» it means that really the engine is at 90 ºC. so, in a metal top engine normal temperature would be pointing at somewhat between the «80 ºC» and «60 ºC» dashes pointing to about «70 ºC», when it really is at 80 ºC. you can confirm this by plugging in diagnostic software like multi ecu scan. anyone correct me if I am wrong, please.
iF that is the case, Jacob;
That you now have a metal-top engine (CF1) with a plastic top /head? (CF2) fitted,
Then you will indeed have different engine management.
On the CF1 engines- there are two temperature senders next to the thermostat. One sends to the ECU and one to the dashboard instruments.
On the CF2 engines, there is one sender, and the dash instrument reading (coolant temperature) is derived from the ECU itself.
Jacob- it really sounds like a bad thermostat. But i'm a bit confused about your engine variant- can you post a picture of your thermostat, on the visible side of the engine, and that will answer a lot of questions... (Can you work out how to post a picture..?)
Hello, how are you? I am from Argentina. I have a problem. When the engine reaches 90 °, I accelerate alone. I have a 145 2.0 alumnium top engine
well, this is somewhat embarrassing, as service manuals as contradictory, misleading and incorrect.
there are 2 different thermostats available for TS engines.
V1, only for CF1 engines (metal top), part no. 60614140, specs says it opens at 83 ºC
V2, for CF2 engines (plastic top), part no. 60653946, specs says it opens at 88 ºC
this information confirms what I wrote here.
I own a CF1 146 1.6 TS and temp sits at between the «80ºC» and «60ºC» marks (misprinted dashboard) meaning that is really about 80 ºC.
I aslo own a CF2 156 1.8 TS and temp sits at almost «90 ºC» meaning that is really at about 90 ºC.
both thermostats in good working order already replaced at least once.
what is confusing is that 146 service manual does not mention this specs differences between CF1 and CF2 engines. only refers to thermostat opening at 83 ºC.
elearn for 156 either, and only mention opening at 83 ºC
gtv service manual, the same.
only found 88 ºC opening temp in elearn for the 147.
what is more confusing is that, according to eper parts list, there are versions of CF1 TS engines using the V2 thermostat and therefore working at 88 ºC.
my CF2 1.8 TS runs at an indicated "90" dead.
no movement, once up to temperature at all.
(thanks, I suspect to the efforts of former owner; Jeremy G!)
Jacob- from what I can see in those images, you have a CF2 motor, thermostat and coolant return pipe. It all looks pretty standard and up to date.
Having said that, and with deference to Alfizta; I cannot tell which thermostat that is; although it appears identical to mine, and still has the factory clips on the return line; suggesting originality.
well, hope this helps
V1, part no. 60614140, only for CF1 engines
Well done, Alfizta!
but I have a remark/correction to make to myself. been digging on eper and V1 of thermostat has been used for CF2 1.4 TS (but not 1.6 and above) engines as well. your car has version 1 of the thermostat in CF2 1.4ts, so all looks OK.
about your question about the engine being «cooked» from overheating with a wrong thermostat, it seams unlikely, as v2 (hotter version) wouldn't fit the hose setup. anyway, cooling fan would avoid such incident, I think, if somehow v2 thermostat was fitted. anyway, eventually, could lead to a premature head gasket failure...
the engine in those pictures looks PRETTY clean
I doubt the head gasket has ever been replaced on Jacob's car (as it stands)
about temp readings on your new dashboard, 1.4 and 2.0 ts dashboards have different part numbers, so might be incompatible. that way, can't help you with that. better to fit diagnostic software to know to what real temp the display corresponds to.
dante giacosa and alfizta, wow... thank you for your responds . That's a lot to process!
When alfizta mentioned earlier about the CF1 and CF2 engine issue with the metal and plastic top, quote
"old versions of TS engines (metal top) work at around 80 ºC, while newer versions (plastic top) my 98(not sure) and after work at about 90 ºC.
there are two versions of temp gauge dashboards, earlier with an 80 at the middle and newer with the a 90 at the middle. it happens that in the earlier dashes looks like the 80 (and 40 and 120) were misprinted and actually indicate 90 ºC (50ºC and 130ºC). so, if in an older version gauge points to «80 ºC» it means that really the engine is at 90 ºC. so, in a metal top engine normal temperature would be pointing at somewhat between the «80 ºC» and «60 ºC» dashes pointing to about «70 ºC», when it really is at 80 ºC"
...it struck me and made cense because i remembered a conversation i had with the mechanic that fixed the engine replacing the seal gasket (and etc...). Please note that he is a general mechanic, very good in his job, but not a specialist alfisti. So he said that the gasket he initially got based on my chassis/Vin number didn't fit properly (!!!). He then checked with his supplier to find out that an older gasket version fitted, saying that it was for a metal top engine (SF1), thus older then my original (Feb/1999).
At that time i didn't have the right input to process this situation so i rested upon his specialty as he suggested that i wouldn't face any problems while the engine seemed to work fine with all the peripherals and especially with the ECU unit (which was the original of my car - CF2).
So it ended, unfortunately, with having a CF1 motor on a CF2 environment covered with my original first plastic cover ...what a mess!!!
I have hooked up twice the ECU to a diagnostic system and it shows intense fluctuations of the temperature. The second level of the fan starts quite frequently and it seems that it does the job but generally the temperature is overall quite high and falls on normal levels only on open roads. So i am concerned as alfizta mentioned quote "...if somehow v2 thermostat was fitted. anyway, eventually, could lead to a premature head gasket failure..."
...thank you both for all that info. It's mostly appreciated and is very helpful. I think that i must have an extended conversation with my mechanic. Guess that i must somehow try to see how a V1 thermostat may work (correct me if my thought is wrong)...
EDIT ...oh now i get it! Sorry i got it wrong. I have i V1 thermostat that's for sure (thought had a V2 from the descriptions, stupid me...) The engine, according to the incident with my mechanic about the gasket, is probably CF1. But even if it was CF2, it would work because it is a 1.4 TS where V1 thermostats are also legit. So either way as far as the thermostat is concerned things seem to be Ok. Right?
But what about the ECU? What if is a ECU From a CF2 managing a CF1 engine. Would that matter?
this is a fascinating problem
I'm not sure CF2 engine management would run CF1 mechanicals
as an isolated observation, I think the coolant sensor has a different number of wires per version;
correct me if I'm wrong someone..?
Interesting bit of black tape round that loom...
Hey Jacob- can you post pictures of your coolant expansion-tank and the relays under the cover in front of the battery..?
Hmm...I think the problem is simpler than how you see it.
CF1 and CF2 can be retrofitted without major problems, so I don't think this is the reason of the issues you face, only the head gasket varies in thickness(My99 has more CR)
Me think that you instrument cluster doesn't match with the temp sensor fitted to the engine, has your's the chrome rings around the gauges?
Your thermostat should open at 83ºC (both versions works at 83ºC) and looks like you have the correct temp sensor by looking at the pics you provided, so all this is okay.
Then, if all above is correct, then you can start looking into cooling issues. Best is to get a diagnostic tool to compare temp readings ECU vs Instrument cluster, check 1st and 2nd speeds of radiator fan and so on..on open roads, engine temp should be near the opening temp of the thermostat, even if you trash it, if it goes up when asking for power, you radiator is internally clogged (usual). The thing is that you say you have most problems on slow, city driving..what's the ambient temp out there?
After the valuable info got here and processing all the input, i did some digging concerning the thermostats.
What i found out agrees with @alfizta post about thermostat types and operating temperatures. But it seems that a detail makes a difference and it has to do with the 1.4L capacity TS CF1/2/3 engines then the rest TS engines.
Regardless of year construction, all 1.4 16V T.S engines (and earlier some AR155) go with the following thermostat type/variation corresponding to these part numbers and operate at 83°C.
OEN 46550153 — ALFA ROMEO
OEN 60614140 — ALFA ROMEO
OEN 46550153 — FIAT
OEN 60614140 — FIAT
OEN 46550153 — LANCIA
OEN 60614140 — LANCIA
All CF1 engines (metal top) except 1.4L go with the following thermostat type/variation corresponding to these part numbers and operate also at 83°C.
OEN 60602148 — ALFA ROMEO
OEN 606 0214 8 — FERRARI
OEN 60602148 — FIAT
OEN 60602148 — LANCIA
OEN 60812410 — FIAT
Take a close look on this two thermostat and you will notice the difference in their circulation system.
Later on CF2/3 engines (plastic top) except 1.4L are compatible with the following thermostat type/variation corresponding to these part numbers and operate at 88°C.
OEN 60609025 — ALFA ROMEO
OEN 60653946 — ALFA ROMEO
OEN 60814382 — ALFA ROMEO
OEN 606 5394 6 — FERRARI
OEN 608 1438 2 — FERRARI
OEN 60609025 — FIAT
OEN 60653946 — FIAT
OEN 60814382 — FIAT
OEN 60609025 — LANCIA
OEN 60653946 — LANCIA
OEN 60814382 — LANCIA
So from what it seems, TS engines nominal operating temperatures vary according to variation and capacity. CF1 and 1.4L engines have thermostats working at 83°C thus the spectrum from 70°C to 90°C cooler/water temperature should be considered as optimal.
On the other hand CF2 and CF3 engines except 1.4L have a bit higher range of optimal operating temperatures as their thermostats work at 88°C. So in this case operating temperature range between 80°C to 100°C should be considered as nominal and optimal for this engines.
One more thing i came across, but need some more research, is that CF1/2/3 engines although seem to be identical as the engine body/block and valve head is concerned, they are actually only close to the row of manufacturing while they have slight differences in the body part metal thickens, and major differences in the base alloy used. So it makes sense that different thermodynamics apply to each variation having an impact on the optimal operating temperatures.
...so in my case, 100°C for a 1.4L TS although nominal for CF2 and CF3 engines, is a bad, bad thing
This is getting pretty technical.
So, do you 'know' what you need to know then..?
I'm sorry I can't bring any more to the table, so to speak..
okay- sounds like a plan
are you sure that you have the right thermostat, then..?
I agree with Antonio. My ph1 or cf1 alway hangs at 80degrees. However i suspected this might not be the correct temp as my ts 147 always hangs at 90 degrees in the middle of the temp gauge. However my 145 was never this stable in the past and quite often i had to pull over to let the engine cool. Since the rebuild it has been perfect cold or warm weather. First cause of my overheating back in the day waz a radiator that had no fins left. Replaced this and it was better. Second thing was when i replaced the thermostat i tested the old one and it did not open when submersed in boiling water. So i also had a knackerd radiator thermo. The other thing waz the amount of s**t i had in the coolant. Change the coolant regular. Since the rebuild here is what happens. Stuck in traffic for half hour the temp goes from 80 to 90 and then the fan kicks in. Apparantly there is a second temp where the fan kicks in again this is when it gets to 95-7 degrees. By the way during the rebuild i replaced the radiator coiled sensor that sits in the rad. My original looked worse for wear. It's all happy days now.
i think the radiator coiled sensor is a PH1 feature.
As I understand it, the PH2 radiator fan speeds are picked by the ECU from the coolant sensor on the thermostat.
I have indicators actually (!) to show radiator fan functionality, and I have never seen the 1st fan speed operate.
The car sits at a solid 'indicated' 90 degree coolant temp, and I've been in a lot of traffic in the current 'heatwave' on the way down South yesterday- and I only ever get fan speed 2.
I think the 1st fan speed might be more associated with the air conditioning, which I have yet to get functional.
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