Usually after I start my 98 Disco it sounds like it is a lot louder then normal, and then after a few minutes it goes back to normal. Some one told me the VSC fan, but I have no idea. I know its not much info, but if any one has any ideas, please let me know. chris@suntechindustries.com
Loud roar on start up?
- Thread starter CRASH05
- Start date
That does sound like the Fan or clutch fan causing this sound. Easy way to check to see if it is bad is to run the engine for 20 minutes or so, then open the hood and spin the fan, if it spin real easy, it is bad. If it spins, but only about 1 turn or less it is still good.
Joey,
it is inaccurate at best.
The roar at the start-up is a common thing to happen, not only for rovers. The viscous clutch of the engine-driven fan is farly stiff when cold, and it "loosens up" after a few minuts of engine operation.
How does one determine if the viscous fan clutch is bad? My '89 RRC fan clutch was pretty tight when it was hot, but that clutch was close to seizing and seized soon. My [other 4x4] fan clutch feels very light, but it does lock up quickly as the temperature increases. On that particular clutch, the temperature range between light and tight is about 5F - and it can cool down by 5F by the time you stop the engine, get out of the vehicle, and reach for the fan.
In contrast, my yet another 4x4 has a heavy-duty clutch that always feels tight. And it never gets hot, so I was never able to feel what it is like when it is locked!
By the way, if a fan clutch allows the fan to spin an entire turn under any condition, it is definitely loose.
it is inaccurate at best.
The roar at the start-up is a common thing to happen, not only for rovers. The viscous clutch of the engine-driven fan is farly stiff when cold, and it "loosens up" after a few minuts of engine operation.
How does one determine if the viscous fan clutch is bad? My '89 RRC fan clutch was pretty tight when it was hot, but that clutch was close to seizing and seized soon. My [other 4x4] fan clutch feels very light, but it does lock up quickly as the temperature increases. On that particular clutch, the temperature range between light and tight is about 5F - and it can cool down by 5F by the time you stop the engine, get out of the vehicle, and reach for the fan.
In contrast, my yet another 4x4 has a heavy-duty clutch that always feels tight. And it never gets hot, so I was never able to feel what it is like when it is locked!
By the way, if a fan clutch allows the fan to spin an entire turn under any condition, it is definitely loose.
I will not argue that Peter. I was just speaking from my personal experience....but you seem to have more than me when it come to Rovers....
nope, it isn't rovers, mostly. It's my frustration with being unable to tell whether the fan clutch is good or bad -
loose or tight is relative,
hot or cold is relative,
a tight fan when hot may not mean that the clutch is good, and
a loose fan when hot may not mean that the clutch is bad.
The only thing I've noticed among nearly all trucks - the fan makes a lot of noise upon a cold start, and quiets down somewhat when the engine warms up a bit.
loose or tight is relative,
hot or cold is relative,
a tight fan when hot may not mean that the clutch is good, and
a loose fan when hot may not mean that the clutch is bad.
The only thing I've noticed among nearly all trucks - the fan makes a lot of noise upon a cold start, and quiets down somewhat when the engine warms up a bit.
upon startup of a cold engine, all of the fluid within the viscous coupling is drained to the bottom so it locks-up. Once the unit is spinning, the fluid is dispersed and if the unit is in good operating order, it will bein to slip and quiet-down.
Take a read on the coupling to understand how the unit works, and you will see that it all makes sense.
Take a read on the coupling to understand how the unit works, and you will see that it all makes sense.