You are possibly right, but aside from buying 5 samples from 5 different brands (25 total), and testing them, do you have a reliable suggestion? Cause no single brand or source is repeatable at this point.Got a friend that installed one of those. It didn’t get to 1.4 ratio.
I have been using this one (from Autozone) for the last year and it works great without issues. Keeps temperatures about the same as original before that one was failing.Anyone tried this style with blade recently? Looks to be the aftermarket version of the unit used on the MB I4 on the NCV3 (which is phyiscaly a similar size to the T1N version).
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haven’t had any issues with them. They are much quieter when they lock so you really have to listen for it, Haven’t tried the Chinese version only the German ones.Anyone tried this style with blade recently? Looks to be the aftermarket version of the unit used on the MB I4 on the NCV3 (which is phyiscaly a similar size to the T1N version).
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The annular ring at the blade tips makes them a fair bit quieter I would guess. Also a bit more efficient.haven’t had any issues with them. They are much quieter when they lock so you really have to listen for it, Haven’t tried the Chinese version only the German ones.
I can ship you out a German one if you’d likeThe annular ring at the blade tips makes them a fair bit quieter I would guess. Also a bit more efficient.
Yes- installed one June of last year per https://sprinter-source.com/forums/index.php?threads/12364/post-1207550Anyone tried this style with blade recently? Looks to be the aftermarket version of the unit used on the MB I4 on the NCV3 (which is phyiscaly a similar size to the T1N version).
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Is the vertical thing unique to the sprinter? In any event I forgot and laid mine flat so time will tell.Thought that had been done to death but seen as you mention it...
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To the best of my knowledge it applies to all none electronically controlled viscous clutches.Is the vertical thing unique to the sprinter? In any event I forgot and laid mine flat so time will tell.
Well, when I filed my pin down 0.005", it did cause the fan to come on a little earlier. Has to be really hot conditions, of course.I have two clutches, both used, both from Europarts, about a year apart (last one was ordered a year ago or so. Neither clutch has ever made the obvious roar or lockup, we don't spend too much time in hot weather, and I just drove to keep the coolant temps reasonable most of the time. It was really only an issue when running at 100% load for more than 10 minutes in hot weather.
I took both clutches apart as far as reasonable. Despite being different brands, both probably came from the same factory. The brass pin/rod which controls the locking behavior was over 9% different between the two, and it was obvious that someone hand ground each one. This is likely a calibration process.
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As an experiment I filed down the pin in increments, until it was in its fully out position at ambient temperature. Under none of those circumstances did the clutch lock. Instead, under all situations I can test, it would run at around 980RPM at idle. Even when totally ambient, and at cold start. This was the same behavior of the other clutch as well.
This makes sense, as with my working factory clutch, my AC evap fan would come on almost immediately when idling in hot weather unless the main fan was locked, as in the unlocked position it doesn't move much air. With the aftermarket fan clutches, it rarely comes on in temps under 95F, as the clutch is always partially locked, but never fully locked.
Here is my hypothesis, I can conclude that these clutches are faulty. They are not capable of locking fully, and slip excessively in the locked position. The factory techs are getting around this issue by filing down the pins during the calibration process, so that the clutches are always in the locked position, which allows them to pass the bench test, as the test is not long enough to identify a partially locked clutch.
I suspect there is an internal fault in the rotor fins, or the fluid quantity or viscosity is insufficient to produce enough torque to drive the fan at ~80% of shaft speed.