Hello all Would anyone have an old 355 thermostat out to measure in metric measurement or know which model Fiat X1/9 is the correct one to purchase. There are 2 at 82C but different dimensions Thanks in advance
The dimensions are: Flange: 56 mm Height: 32.5 mm (flange to foot, 33 mm will do) Foot: 32 mm (34-35 mm is also fine) This example is for Fiat X1/9 which suits 348/355: Image Unavailable, Please Login
Some background information here... https://www.ferrarichat.com/forum/threads/348-355-thermostat.496181/ Do they all come with the bleed hole or do you have to drill it yourself? http://www.birdman308.com/service/thermostat/thermostat.htm
It's interesting to note that when testing the thermostat (out of the car), it's recommended that you use a normal coolant mix rather than just water. http://www.tridon.com.au/databank/documents/Cooling-Catalogue.pdf
What exactly does the 82C correspond to? The Workshop manual has expansion dimensions at various temperatures: 20C (cold) 32.5mm 75C 41mm 96C 44.5mm The Tridon manual mentions: "Commencement to open" or "crack" temperature (usually 10~14C below full open) Is 96C full open? If so, crack temperature should be 96C minus (10~14)C = 82C~86C But if the valve has already moved 8.5mm (41mm minus 32.5mm) at 75C, doesn't this mean that the valve has cracked well before 82C?
There seems to be something wrong with the thermostat specs given in the workshop manual (perhaps a detail just copied from some earlier Ferrari model with a 72C thermostat or a typing error - "75" should read "85"). The temperature stamped on the thermostat should be its wax melting temperature, i.e. the temperature when the wax starts expanding rapidly. This temperature point is not exact, perhaps +/- 2C. The thermostat will be opened slightly before the wax melting temperature due to the (solid) wax thermal expansion and continue to open further (slightly) after the wax has fully liquified (rapid opening completed), again due to thermal expansion of the liquid, something like the curve on this diagram: Image Unavailable, Please Login
The 348 workshop manual has the same text. Should the F348 also be 41mm @ 85C? I found one Fiat X1/9 (Fiat P/N 4220309) 82C thermostat on eBay for A$60 (U$45) in the original Savara brand (Savaras are also OEM on Ferrari 308's) https://www.ebay.com.au/itm/Fiat-X19-X1-9-128-130-Thermostat-Savara-82C-4220309-/332070868725?hash=item4d50f756f5
I believe an 82C thermostat will open significantly by 85C so it should be about 41mm, subject to +/- 2C tolerance. Savaras are vintage now, NOS will be at least 20 years old. Perhaps it is better to go for more fresh production like Wahler (~GBP 31) or Tridon (AUD 31, you should know whether these Australian made thermostats are good or not).
Or you can get a Stant equivalent for under $5.00 https://www.rockauto.com/en/moreinfo.php?pk=48785&cc=1104949&jsn=461
In the "birdman" link above, this was written about the Stant: On the far right is a Stant that you can get for about $10 at NAPA. It will fit the car but it has a slightly smaller flange size at 54mm. The plunger is the right size to work. However, the hole in the middle of the thermostat (what I'm calling the Inner Diameter "ID" on the pic) is quite a bit smaller. The Savara has 754 square millimeters of area in the hole for coolant to pass through, and the Stant only has 615. That's 18% less flow. Enough to make a difference? Maybe. Maybe not.
Can't say I'm familiar with the brand. Looking at their website, I'm not sure if all their products are made in Australia. Tridon is a distributor as well as a manufacturer. I'll have to check my local parts store. None of these brands seem to scream high quality.
18% less area does not translate to 18% less flow as the flow velocity will go up to compensate for the smaller opening. The change in flow rate would probably be small since any increase in pressure loss across the T-stat would likely be small compared to the over all pressure drop through the cooling system; engine, hoses, radiators..... Not to mention that the diameter if the hole is not the only thing determining flow area through the T-stat. In any event there are alts to the $236 one that comes in a yellow box with horses on it.
Been using Tridon t-stats for 25/30yrs no dramas with there quality. I don't see the difference in testing opening temp with water or coolant 82 is 82C but I can see it's function clearly in water
I probably should have explained my statement a bit better. The use of Water compared to coolant is in regards to testing thermostats not the use of water in the car that's a coolant only for me
I have one. it is a Behr. Dimensions as follows Top Flange = 56mm Bottom flange = 34mm Distance from the top to bottom flange is 32.5mm. FYI I changed it out to a 86 Deg. C one to increase the normal operating temperature in the cooler northern climate where I live.
This is all I can find: Stamped on the upper flange - BEHR-THERMO?-TRONIC-ITALIA B.295 82 9B On the stem (under the spring and above the lower flange 82 BT1.020 8M (The ? after THERMO is because there is a letter (could be T) where the 2mm port is drilled in the top flange so I cannot say for sure what it is.)
It is BEHR-THERMOT-tronic-ITALIA (I have one) and the number you have should be B.296.82. However, there is no number (B.296.82 or other) stamped on my Behr (from Eurospares). The Thermot-Tronic should actually carry the number 6.036.82, according to the Behr catalogue, and the B.296.82 is just Behr. Anyhow, the two have identical specs. Image Unavailable, Please Login Image Unavailable, Please Login
