The engine cooling system in my 1997 BMW 318ti is on the fritz. I’ve but to diagnose it correctly, however I do know the issue is someplace alongside the traces (actually) that carry coolant to the engine and assist the 1.9-liter inline-4 cool off. That’s been essential in these canine days of summer season, which persist in Texas despite the fact that we’re nearing the autumn. In my discussion board search to glean data, I’ve come throughout a variety of good things, together with an outdated video that describes how the thermostat in my automobile works in a method even I can perceive.
The 318ti is sort of at 210,000 miles, however the little hatch hasn’t precisely gone by means of hundreds of hassle-free miles since we final checked in. I’m on the outset of a cooling system refresh — new traces, new water pump, new plastics, new thermostat, and a coolant flush — and I used to be studying up on my favourite discussion board, once I got here throughout this video from Mahle, which explains how an outlet commonplace thermostat works:
By the way in which, there’s additionally a video with narration that explains what’s happening. And there’s a video that explains how trendy map managed t-stats work. The narrated video taught me that the right technique to say Mahle is outwardly “maw-luh.” Whoa.
Anyway, the contents of the video are simply as attention-grabbing: There’s wax that melts and solidifies inside a brass cylinder within the t-stat meeting, which operates based mostly on engine temperature, impeding or permitting the movement of coolant through the use of the heating and increasing wax to open or shut a valve. I love how easy the method is, but it stays efficient.
I doubt the repair to my automobile is the t-stat alone, however the remainder of the elements alongside the chain are probably due for alternative at this level, anyway. The E36 has infamously fickle cooling techniques. The fan stays my prime suspect; maybe the resistor has gone.
What’s occurring in my 318ti is the radiator fan seems to not activate in any respect. Neither the excessive nor low stage work, which led me to exchange each relays simply to be secure. The low stage relay is infamous for quietly breaking, inflicting the fan to spin solely when engine load will increase, say, while you activate the A/C within the automobile.
But I suspected the excessive stage had lastly gone, too, as a result of up to now, every time I might discover the temperature needle tick proper (indicating increased temps) all I needed to do was activate my A/C and the fan would kick on. That stopped working, leaving me with out a fan in the midst of summer season.
So, I wired the fan on to my battery to get my automobile to the store. Weeks later, I used to be nonetheless precariously wiring the fan on to the battery as a way to pressure it on like some barbarian. But as any proprietor of an historic shit field can attest, there are ranges of annoyance, and typically we put up with advert hoc repairs and shitty workarounds till one thing disastrous occurs. For now, I’ll follow driving solely at nightfall and daybreak, when the ambient temperature is not set to bake.
Source: jalopnik.com