Maybe I'm missing something or maybe my car is missing something. I have a 1989 FJ62 I just replaced the alternator and I cannot get the smaller belt tight. Does the alternator just slide back and forth on the bracket or am I missing a tensioner bolt. As far as I can tell it has the pivot bolt at the bottom and then it rotates back and forth on the uper bracket. I have it as far over as it will go and the belt is still loose.
How do i get the alternator belt tight? (1 Viewer)
- Thread starter Madronesfj62
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- #3
Thanks, from what I can see in those pictures I am missing the tensioner bolt. Mine looks like the first picture where the top bolt on the alternator just slides back ama forth on the bracket. If I have the alternator as far as it will go to one side how can I get it tighter. Can I buy that tentioner bolt somewhere and how would it make it tighter.
Are you at the full extent of the slotted bracket? Does the new alternator have the same size pulley. Is the new belt the same length as the old? If you have room in the slider bracket you either need to use a pry bar to tension the bolt while you lock it down or find parts to assemble the tensioner bolt (better option)
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- #5
I am 99% sure I am at the full extent of the slotted bracket. I used a prybar to pull it as far over as I could before I locked it down. I bought a alternator from www.qualitypowerauto.com/item_456/Toyota-Land-Cruiser.htm it appeared to have the same size pully as the old one. I suppose I should have replaced the belts when I was changing the alternator but I didn't since the belts were changed 5k miles ago.
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- #9
So I decided to get new belts and install those. That solved the tightness issue, weird that the belt I have been running for the past 6 months was just slightly larger then the new belt. With the belt now tight I thought that would be the end of the issue. unfortunately now the new alternator is making a whining noise that I can't figure out. I made sure everything is tight but I'm still getting this whining noise.
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- #10
Here is a quick video of it.
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- #12
I can rotate 90 but not super easy to rotate. I will try and loosen a little. See if that helps.
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- #13
So I loosened the belts..and nearly got rid of the whine..I still hear it a little. Now I am having other issues that I can't explain. At idle in park the volt meter on the dash reads right about 14 with AC lights radio all on. When I put it in drive idle speed drops and the volt meter reads under 13, close to 12. If I turn on a turn signal it drops really low.
The new alternator I got is a high output alternator. I also installed a new battery.
Do I have wiring issues? Is my idle speed too low in drive? It drops from around 1k in park to 800 in drive.
Picture of gauge at idle, in drive and in drive with turn signal on.
The new alternator I got is a high output alternator. I also installed a new battery.
Do I have wiring issues? Is my idle speed too low in drive? It drops from around 1k in park to 800 in drive.
Picture of gauge at idle, in drive and in drive with turn signal on.
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Your voltmeter is more optimistic than most FJ62 voltmeters. Measure the voltage using a meter at the battery and see what your system voltages are under those conditions, and report back. FJ62 alternators aren't known for putting out gobs of amps, and do tend to show a big drop under load.
An alternator's output is rated for a given speed usually. So even if the unit you have says it is rated for 150 amps lets say....that might not be output until the alternator is spinning at 6000 rpm. So at idle or low rpms you may not be getting full output. As long as the alternator pulley is smaller than the crank pulley you will be getting some rpm multiplier but if your alternator is not spec'd out for low revving engine it may be problematic.
Also the AC won't effect the charging and battery voltage other than the blower motor. The AC will rob power from the engine to turn the compressor. Your main power draws will be the ignition, EFI, headlights, brake lights, radio, and blower motor. Unless you are running a huge stereo system, lots of custom accessories, a winch maybe, or lots of big lights there is probably no need for a beefy alternator. You would likely get more improvement by going to large gage battery cables, alternator leads, starter lead, and ground straps.
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- #17
So the voltage drop isn't a concern? I got the high output alternator because of future upgrades, lights, winch etc. that I plan on getting.
My concern is at night, running headlights, stereo, and then sitting at a light with the blinker on the voltage seems to really drop and the headlights start to dim. It hasn't stalled or anything just seems strange that the voltage drops.
I have read posts about running another wire from the alternator to the battery with a fusible link. Would that help? The power windows and door lock draw a ton as well. Rolling down a window with the blinker on in drive at idle makes the voltage drop like crazy.
Should I not be concerned? Or should I try and mess with wiring.
My concern is at night, running headlights, stereo, and then sitting at a light with the blinker on the voltage seems to really drop and the headlights start to dim. It hasn't stalled or anything just seems strange that the voltage drops.
I have read posts about running another wire from the alternator to the battery with a fusible link. Would that help? The power windows and door lock draw a ton as well. Rolling down a window with the blinker on in drive at idle makes the voltage drop like crazy.
Should I not be concerned? Or should I try and mess with wiring.
Beefier battery cables and alternator cables will be beneficial no matter what else you do. My preference has been 2 gage or 4 gage welding cable. Makes a very noticeable difference.
For the future you might consider running a second battery to increase your power reserve.
And maybe you can run a smaller pulley on the alternator? Others will know if that’s an option.
For the future you might consider running a second battery to increase your power reserve.
And maybe you can run a smaller pulley on the alternator? Others will know if that’s an option.
After my engine conversion my voltmeter would fluctuate and show a voltage drop like you describe. I put a tester on the alternator and the voltage was steady with everything turned on that I could find. The fix was a body ground wire. It was an easy fix but not easy to find. Try either a wire from the battery negative or use a screwdriver from the negative post to the body and watch the gauge as you turn on accessories.
