Okay to run engine without belts?
07-10-2004, 03:29 PM
#1
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Okay to run engine without belts?
I suspect a bad alternator and/or cooling fan bearing is the sound I hear from the engine at 1800 and then again at 2600 rpm.
To check, I think I could just remove each belt and listen. But, I just want to make sure there won't be other problems if I do this for a minute or so.
What say the group? Okay to run the engine for a short while with no belts?
To check, I think I could just remove each belt and listen. But, I just want to make sure there won't be other problems if I do this for a minute or so.
What say the group? Okay to run the engine for a short while with no belts?
07-10-2004, 04:32 PM
#2
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With a stone cold engine, dont worry about it. Just dont run it for more than 20 seconds or so. Dont rely on oil temp to indicate if the engine gets hot since there is a delay between hot engine parts and hot oil..
You should only need to run it for less than 10 seconds to verify your noise. Or, just remove the alt. belt and give it a try
You should only need to run it for less than 10 seconds to verify your noise. Or, just remove the alt. belt and give it a try
07-10-2004, 04:33 PM
#3
Rennlist Member
I've run my engine for a few minutes with either/both belts removed to diagnose
a bearing noise. Remember to stack the shims and sheaves on the alternator shaft once you've removed that belt because the fan hub only slides on the shaft. The stack and nut holds the fan onto the shaft. FYI, you can actaully drive about 80 miles with no alternator belt, until the battery goes dead, the lights start flashing on the dash, and you coast to a stop 300 yards from the fringe of cellular service.
I wouldn't drive to the mail box on my drive way without the fan belt intact ...it being air cooled (the car not my mail box). But it's all right to run a few minutes.
My problem was a bad bearing in the front of a rebuilt alternator (near the voltage reg.) that I had just installed. The alternator spun ok on the bench, but it had some slop in the shaft radially. Got another rebuild from a different supplier, and all was well.
later, Kevin
a bearing noise. Remember to stack the shims and sheaves on the alternator shaft once you've removed that belt because the fan hub only slides on the shaft. The stack and nut holds the fan onto the shaft. FYI, you can actaully drive about 80 miles with no alternator belt, until the battery goes dead, the lights start flashing on the dash, and you coast to a stop 300 yards from the fringe of cellular service.
I wouldn't drive to the mail box on my drive way without the fan belt intact ...it being air cooled (the car not my mail box). But it's all right to run a few minutes.
My problem was a bad bearing in the front of a rebuilt alternator (near the voltage reg.) that I had just installed. The alternator spun ok on the bench, but it had some slop in the shaft radially. Got another rebuild from a different supplier, and all was well.
later, Kevin
07-10-2004, 04:47 PM
#4
Rennlist Member
After reading Walrod reply, I stand corrected. In my case the sound was apparent from the get go at idle and I could tell immediately that the sound was from the alternator while trying the different combo's of belts. I ran it at most probably 30 seconds each iteration. Keep track of the run time and heat of the engine, but I would feel safe to go a minute with fan belt removed, running and playing with the throttle to troubleshoot the sound.
07-11-2004, 08:05 PM
#5
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Air cooled motor cycles idle with no fan, and don't seem to have problems. I would not worry about a minute or two with no forced cooling, You are not generating much heat at idle, and there is always some natural convection around hot parts. I say it is not problem, even if you run for a couple of minutes.