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Last post on May 21, 2013 at 8:27 PM
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#599 of 2865 Re: Online advice [srs_49]
by thecardoc3
Dec 04, 2012 (6:18 am)
Question - how do you measure the resistance of the fuse without removing it from the circuit? Do you just measure a fuse in the parts bin, and assume it's close enough to the one in the vehicle?
Actually what I said was.
A fuse is a resistor, so any parasitic drain will cause a small voltage to be measurable across the fuses terminals. Do you have a voltmeter that is accurate into the 10,000ths of a volt or smaller? (.000XX) That is how you go about locating what circuit the drain is on. A low amps probe allows a technician to measure the drain on the car without opening the electrical system and clearing out all of the memories as well. Some of those are accurate down to about 5ma (.005 amps).
Could use a non-invasive current (Hall Effect) probe, providing you can clamp it around the wire of interest.
So the answer is yes, measure the current draw, and if it's excessive use can use the voltage drop technique to identify the circuit.
Question - how do you measure the resistance of the fuse without removing it from the circuit? Do you just measure a fuse in the parts bin, and assume it's close enough to the one in the vehicle?
It is possible to measure the resistance of a fuse with the correct tools but a regular ohmmeter isn't the correct tool. Besides, it's easy to calculate the fuse's resistance by measuring the current through it, and the voltage drop across it. The fun part about this is the fuses resistance isn't fixed. Like anything else the temperature of the fuse makes quite a difference in it's resistance, which of course explains exactly how they work when you think about it for a few moments.
Dec 04, 2012 (1:44 pm)
I read this entire thread and wanted to say thanks for all the great info.
And insight. I'm a backyard hack, but a stubborn one, so I only use a garage occasionally. But when I do I'll look at it a little differently now.
The only thing I have to add is, don't buy the cheap rotors!! Even if you're lucky enough to not get the ones that shatter, I was buying $13 fronts for my old 97 Grand Marquis and had to replace them more often than the pads! Also, while the rotors on my 03 are hatless, because they are so much bigger than the 'hatted' rotors on my 85 Town Car they seem to weigh about the same.
Bartbarter
#601 of 2865 Re: Hello all. [bartbarter]
by stickguy
Dec 04, 2012 (5:46 pm)
good point about the parts, and I will bet that "doc" will agree. Not worth buying cheap parts, unless you like to replace them and do your own work. and have lots of spare time.
but when you are paying to have a job done, usually (or at least often) the labor is the biggest part of the job. So saving a few dollars on an inferior part seems counter-intuitive to me.
#602 of 2865 Why is getting wheels balanced so difficult???
by oldbearcat
Dec 04, 2012 (9:31 pm)
Where I live, the past few times I've replaced the tires on my vehicles, I've had to take the car back 3 - 4 times for a re-balance for the shop to get them properly balanced. I've had this problem with local independents and national chain tire dealers as well. My most recent experience - I recently replaced all 4 tires on my Honda CRV. I've had the car back to the shop 3 times for a re-balance and they still didn't get it right. Monday I took the car into my local Honda dealer for a brake job, and, had them balance all 4 wheels as well. The Honda techs got the wheel balance right on the money. Is there a shortage of folks who know how to mount and balance tires correctly? Around here the only places that I currently know that will get it right the first time are my local Honda and Mercedes Benz dealers. I'm tired of sitting in waiting rooms for hours while they make multiple attempts to balance the tires correctly.
Regards:
Oldbearcat
#603 of 2865 Re: Why is getting wheels balanced so difficult??? [oldbearcat]
by stickguy
Dec 04, 2012 (9:45 pm)
My guess, a combination of poorly trained low paid techs, the need to get them done quick, and the ever increasing size and weight of the wheels/tires all come into play.
#604 of 2865 Things that are out of balance
by thecardoc3
Dec 05, 2012 (7:11 am)
My guess, a combination of poorly trained low paid techs, the need to get them done quick, and the ever increasing size and weight of the wheels/tires all come into play.
Many of the chain stores pay their techs an hourly wage, plus a bonus based on productivity. Then they turn around and exclude some items from the list from which they accumulate productivity. Guess what one of those items is?
In essence, the techs are "punished" for doing tires, unless they upsell other services from the tire replacement. Then in the case like bearcat, since techs are not paid for a "comeback", they are in effect punished again. The only recourse is for the techs to minimize the personal financial hit by not being paid for installing tires and that happens with speed. When everything goes correctly, nobody else cares what actually happened inside the shop.
Now as far as balancing the tires, there are problems with some wheels on some balancing machines. The wheels have to center correctly in order for the machine to be accurate and many manufacturers have an uncanny ability to make sure their wheels don't mount up without specific adapters. My machine (Snap-On) doesn't do a lot of the 3/4ton truck wheels as easily as it does any car steel wheel. Some of the Jeep mag wheels force me to be very creative in double, and triple checking the wheel/tire assembly which often means that I have to spin it to measure it out, add the weights to balance the assembly and re-spin it to check it. The I have to break it loose, turn it on the spindle and then tighten it up and re-check it again. There have been a number of times that I have found that I have to use different adapters between individual wheels from one car. If the wheel is balanced correctly, I should be able to take it loose, reposition it, and tighten it back up and end up with "0's" again.
The advantage for me is that I don't have to rush through a job like this. I'll take whatever time I need to and in some cases I have had to buy additional adapters for my machine.
#606 of 2865 Re: Things that are out of balance [obyone]
by qbrozen
Dec 05, 2012 (11:52 am)
Hell, I use an old-school bubble balancer at home. I've mounted and balanced at least 20 sets ranging from 14" to 18" in the past few years this way without a problem. Its just what I'm used to. Its the same balancer I used back when I was 7 years old working in my dad's shop.
#607 of 2865 Re: Things that are out of balance [qbrozen]
by thecardoc3
Dec 05, 2012 (2:29 pm)
Hell, I use an old-school bubble balancer at home.
You would add yourself to bearcats list of people who couldn't balance his tires with that.