Hayk

iTrader: (1)

I've been having a rattle on cold starts. It sounded like a loose pulley inside the timing cover, but I think I narrowed it down to my alternator. I used a long pry bar to find the source. Now to confirm the issue, I would like to disconnect the alternator and see if the noise reappears.

Would it hurt the car to run it without an alternator for 5-10 minutes? I just want to make sure before I decide to do it.

StuckInVA

I don't know about your model ES, but recently I had an alternator that wasn't charging my electrical system at all. I took it to the auto parts store down the road this way. Besides running the risk of draining your battery and illuminating your battery discharge lamp I don't think disconnecting your alternator would cause any permanent damage.
I would remember to disconnect the battery while you unhooked it, if you let the battery feed ground you could see some sparks fly.
3VZ-FE here,

BDSL

If the alternator is disconnected, engine will not start / run.
If you don't believe me, see the electrical schematic....or just disconnect the alternator connector and try starting the car.

BDSL

If your battery is strong enough, with a dead alternator (but still connected), your engine can run a few minutes or longer depending on the battery condition.

EEngineer

I think the better solution would be to unhook the accessory belt and then start the car so the alternator and AC compressor are not spinning.

obviously, you are draining your battery, but i heard that people had driven two hours on a non charging alternator on a full battery before

Hayk

iTrader: (1)

I'm sorry I should have been a little clearer. I meant removing the alternator belt, but leaving everything else as is.

BDSL

Yea, I heard that too. The (US) MR2 owners come up to Trenton (Canada) for a MR2 meet every year. And once in a while, I would hear a MR2 would died because of a dead alternator. They would get a new battery and drive for a few hours to make it back home....

moonphase

I had a similar noise on my 1997 es300 with 115,000 mile on the odometer, and after replacing the power steering fluid in the reservoir three times, the noise went away. The noise was very noticeable at the passenger front wheel with hood closed, and with hood open it sounded like it was coming from the timing cover or intake. I used a hand fluid pump to remove the old fluid from the reservoir, filled with new fluid, and drove for ten minutes. Replace the fluid again and drove around a couple days and changed it again. Went about 2 months with no noise on cold mornings and then started up again. I bet the old power steering fluid is the cause.

EEngineer

^that could very possibly be the problem as well. most of our aged cars have imperfect PS pump problems.
mine is leaky, but it doesn't always leak, just when it feels like it. I dumped in a bottle of Lucas and it hasn't leaked since.

when an alternator doesn't charge, you will get a light for sure though.

Hayk

iTrader: (1)

I don't think it's my power steering. I flushed out the PSF this past summer, and I used the pry bar as a stethoscope. The sounds that were coming through the bar were exactly the same as the sounds I was hearing from the outside.

EEngineer

then, replace?
I remember when I bought my ES for $500, the alt was almost dead. when i tightened the dogbone mount, i could hear a loud whine from it. almost like a supercharger haha. so i rebuilt it with parts from another used alt i had sitting around. that alt lasted another half a year before it started to seize and half ripped my old belt. finally replaced it with a newly rebuilt one for $100 bucks when i installed my supercharger

StuckInVA

I don't know what I was thinking when I wrote my original reply. I guess I was just thinking about the time my battery was accidentally grounded when I was swapping alternators on my ford escort. scared the crap out of me.

Does this noise sound almost like a stuck valve or mixed up valve shims? I think I might be having the same issue

I read one of your posts when you said you had mixed up your valve buckets, and you linked a video that was no longer available. Do you, by chance, still have this video? I think this might be what happened with mine. How did you rearrange them back in the correct order??

Although, now I'm not sure if it might be the PS system.

Sorry for hijacking, I just felt it was relevant. I hope you fix your problem.

EEngineer

valve buckets as in the ones in the cylinder head? no they were never mixed up.

moonphase

StuckInVA;
The noise I had sounded like a bearing failing type of rattle or clatter, but somewhat inconsistent. I could pry the top of the timing cover apart slightly and the noise sounded like it was coming from inside the cover. I even listened with my ear on top of the intake manifold and the sound seemed to also be from the intake. I went through the trouble of replacing the upper timing idler roller in an attempt to fix the noise as the idler was bluish from heat, but that wasn't it. The noise would go away after five or ten minutes of warm -up.

StuckInVA

Perhaps it was someone else's post. My mistake. I don't suppose you'd have any suggestions on how to tell if they were mixed up? When I changed my head gasket I had them all in order (in egg cartons) but it sounds like I have a sticky valve or something. IDK not the time or place, I'll dump some Seafoam in the oil and then make a thread if it doesn't go away.