HELP! AHC Pump Issue After Reservoir Drain/Refill (1 Viewer)

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This morning I took the one remaining bottle of fluid I had back to the Toyota dealership I had purchased it from and explained the situation to the parts and service managers. They were both floored, very apologetic and said they had never heard of such a thing. They refunded me the full amount I paid for all the bottles and asked that I send them each the pictures I took. They said they would send those pictures along with their remaining stock of AHC fluid back to Gulf States Toyota (distribution center?) and it would be handled from there. They both seemed sincere so hopefully that issue will get resolved on their end.

I still needed more fluid though so I went to another Toyota dealership and gave the parts manager there the short version. He told me that he had heard of old fluid gelling up like that... not sure if it's true but he said their fluid had only been on the shelf for 2 weeks so it was pretty new. I bought 5 bottles and told him I would crack one and if I found any gel in it I'd be returning them all and of course he understood completely.

So now I'm starting all over again!

I want to sincerely thank EVERYONE who has responded to this thread. I honestly would've been totally lost with y'alls advise. If we meet, beers are on me :beer:

I'd like to thank you also for keeping a level head, working through this, and allowing us to collaborate and share in the findings! I know you just got your 200-series and it probably wasn't what you imagined.

Welcome to the community! I hope you'll have much more positive and satisfying experiences with your LX in the near future. If your built out GX is any indication, I think there's a good chance of that. Cheers. :beer:
 
This is insane, thanks to everyone involved for figuring this out.

Is it fair to assume that that debris (whatever that gel substance is) would be found in unused fluid right out of the bottle, or is it possible that the gel debris only appears once the fluid has been put into use/exposed to heat/agitated/whatever. Basically, can we expect that if a bottle has bad fluid, we would find out by filtering a new bottle?
 
Wow - i'm due for a change. It would be nice to know how to identify the bad batch. I am thinking i'll hold off and make this a winter project to hopefully clear the system.
 
UUUUHHHGGG.
This is the 3rd time I'm taking this pump apart and I'm pretty sure I'm putting it back together wrong.
I go to bench test the pump, plug in power from my 12V source, the motor powers up but no fluid is pumped in either direction.
Are there any "gotchas" I'm missing? I made sure the bearings were facing the right way. Do the gears need to be in a specific orientation?
I'll try to snap some pics and edit this post...
 
I don’t know if it’s been said in this thread, but make no mistake, Toyota knows about this issue. I’ve had two different Lexus dealers in my area refuse to do the AHC fluid service on my 2013 LX because of quality control issues they were aware of with the fluid. One said they have a car on the rack in their shop that has been there since May because of the issue, and they have no idea when it will get resolved.
 
UUUUHHHGGG.
This is the 3rd time I'm taking this pump apart and I'm pretty sure I'm putting it back together wrong.
I go to bench test the pump, plug in power from my 12V source, the motor powers up but no fluid is pumped in either direction.
Are there any "gotchas" I'm missing? I made sure the bearings were facing the right way. Do the gears need to be in a specific orientation?
I'll try to snap some pics and edit this post...
When you put the pump back, the pump gears have two notches that stick out. Are they aligned to the motor part to be able to be turned?

Also double check all the o-rings are in the proper place. I recall lots of small o-rings and it is easy to lose/forget them.

Otherwise, you might have to take the pump apart again and see if anything got gelled up in there. Hopefully not in the lines past the filter. Worst case, you can use compressed air and see if you can blow it out.

AHC Part8.png
 
There is a company who supplies the fluid to Toyota. Can't seem to find the name but here is a site for another supplier of fluid.
 
When you put the pump back, the pump gears have two notches that stick out. Are they aligned to the motor part to be able to be turned?

Also double check all the o-rings are in the proper place. I recall lots of small o-rings and it is easy to lose/forget them.

Otherwise, you might have to take the pump apart again and see if anything got gelled up in there. Hopefully not in the lines past the filter. Worst case, you can use compressed air and see if you can blow it out.

View attachment 2770748

Yes. In fact I have to fiddle with those notches to line up every time I put it back together. Pretty sure I have all of the o-rings...
When I put fluid in the reservoir fluid does flow out the outlet so I don't think there's a clog anywhere... wouldn't that keep fluid from coming out? I assume yes but I could be totally wrong lol
Just checking... does the notch on the bearing face this way? Or the other way?

IMG_0869.jpg
 
Yes. In fact I have to fiddle with those notches to line up every time I put it back together. Pretty sure I have all of the o-rings...
When I put fluid in the reservoir fluid does flow out the outlet so I don't think there's a clog anywhere... wouldn't that keep fluid from coming out? I assume yes but I could be totally wrong lol
Just checking... does the notch on the bearing face this way? Or the other way?

View attachment 2770775
That looks similar to what I have in my photo. That is the part (bearing notch) that I don't have properly documented prior to disassembly. Hence I had reassemble the second time. I didn't take a photo during the second install because I was pissed off (with this AHC stuff) at the time.

20210627_164249.jpg
 
Did you mark your gears and clock them appropriately while reinstalling to make sure the same teeth are aligned? This is something I didn't do, nor did I pay close enough attention to the bearing guide orientation. I was able to reassemble it twice, but on the third time I couldn't get any pressure to build.

The tolerances on everything is pretty tight - another shot in the dark would be filling the pump head prior to putting the reservoir on, and potentially opening up the large hex on the bottom to bleed some fluid out. I always made sure to crack the flare and let fluid run out for a good while before attempting to run the pump, but I wonder if that's not enough.
 
Did you mark your gears and clock them appropriately while reinstalling to make sure the same teeth are aligned? This is something I didn't do, nor did I pay close enough attention to the bearing guide orientation. I was able to reassemble it twice, but on the third time I couldn't get any pressure to build.

The tolerances on everything is pretty tight - another shot in the dark would be filling the pump head prior to putting the reservoir on, and potentially opening up the large hex on the bottom to bleed some fluid out. I always made sure to crack the flare and let fluid run out for a good while before attempting to run the pump, but I wonder if that's not enough.
The first time I pulled it apart the teeth separated and I wasn't able to get a good read on which teeth lined up. I tried to put it back as close as I could to how I thought I saw everything lined up to begin with and took a picture. That answers one of my dumb questions right there, yes the gears need to oriented a specific way.
I'm very close to just ordering a new pump...

2F0FC2CE-186D-4E58-A7EA-4668BE774616.jpeg
 
I hear you, after swapping the pump in and out ~5 times I was done. You do get fast at it though haha. I still have my original pump and want to try and troubleshoot it at some point on the bench, but that'll probably have to wait 6 months.

I'm sure some of the other guys can provide further assistance, but I would try and pre-fill or prime it before firing it up. If there is air in front of a check ball it might not be able to open.
 
This was the photo I took of the pump head before I pulled it apart. Today, my goal is to systematically disassemble/reassemble and each time I reassemble, move the gear on the right one tooth clockwise. If that's where I screwed up then I should (at some point) find the right combination.
In retrospect, dissembling this piece was not necessary. The only clog I found was on the exterior filter. Every piece inside this was totally clean.

IMG_0853.jpg


If this doesn't work, I've decided to buy a new pump lol
 
@grinchy, remember when I said the new whipper-snappers were lapping us with all this AHC stuff?
 
@grinchy, remember when I said the new whipper-snappers were lapping us with all this AHC stuff?
Well they/we have had a little more motivation since Toyota decided to sabotage our general maintenance.
 
I give up!
By pulling apart the pump head I somehow killed any kind of pressure that should build up in there. If I had just left this part alone I'm fairly confident all would've been ok after just cleaning the external filter.

New pump ordered from Dubai. Probably take a couple of weeks to get to my door
 
This was the photo I took of the pump head before I pulled it apart. Today, my goal is to systematically disassemble/reassemble and each time I reassemble, move the gear on the right one tooth clockwise. If that's where I screwed up then I should (at some point) find the right combination.
In retrospect, dissembling this piece was not necessary. The only clog I found was on the exterior filter. Every piece inside this was totally clean.

View attachment 2771020

If this doesn't work, I've decided to buy a new pump lol
Yep, I understand your frustration. I went through it last month as well. I wish someone would have told me no need to disassemble the AHC pump. It would have saved me (and a lot of DIY folks) a lot of headache. In summary, just clean the filter and be done with it, no need to disassemble the AHC pump completely.
 
I give up!
By pulling apart the pump head I somehow killed any kind of pressure that should build up in there. If I had just left this part alone I'm fairly confident all would've been ok after just cleaning the external filter.

New pump ordered from Dubai. Probably take a couple of weeks to get to my door
Thanks for posting your fight and findings with the pump. You have saved many a head ache for doing that.
 

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