AHC Help: Can't clear code

[Jcreme]

My truck is also now throwing the code 1762 abnormal pump pressure. I too used Toyota AHC fluid (bought from a Toyota dealer) from plastic bottles to flush my AHC system. Code won't clear (or at least won't stay cleared). The truck will go from high to low but the process takes a long time.

I just spoke with my Lexus parts manager yesterday. I caught him before their daily staff meeting, so he brought my issue up. Doing anything about this situation lies with the Service Manager. His advice was to call Lexus and start the process by (calmly) explaining what happened. He explained that this is because no matter what the outcome, all assistance will be compensated by Lexus NA. Call Lexus customer service and 1-800-255-3987 (1-800-25-LEXUS).

He also said that there was knowledge about this issue, but that it was not to the degree of issuing a TSB. He said he remembers an email or something to pull plastic bottles from inventory.

I think I got into trouble because I bought my fluid from a Toyota dealer (note my correction above) - Lexus dealers use a lot more AHC fluid.

 

[Jcreme]

Let me tell you the story about the day that @jLB saved Christmas! I didn't want to whine, but this whole situation was a lot worse than I initially described - mostly because we were due to depart on the Hunny's first real road trip on the 26th! All paid for. Nonrefundable. Thousands of dollars worth. And oh yeah, the kids had only one token Christmas gift because the trip was their gift. And there it was, bottomed out. All four corners around. OFF flashing on the dash. And since there are six of us, nothing else we had would cut it. And since "these unprecedented times," rentals (which were mostly not available) were stupid expensive.

I was sweating bullets. In fact, I was up in the middle of the night stressing, researching, memorizing the tech manual, when, a Christmas Miracle! I get a DM from @jLB "hey I think I've seen you around in your 80.. I think I live really close to you.. I have a couple of 100's with unused AHC pumps, I can help you out."

There are not emoji's to express how I felt at this point! Christmas was saved! Indeed jLB was practically walking distance away from me (how had we not met before?) and has a FINE collection of UZJ100's. After a couple of zips of the impact, a handshake, and monumental efforts on my part to avoid inappropriate affection for my new BFF forev-ah, the Hunny as standing a normal ride height by lunch the next day.

OK, so this is a tech forum, and I have learned a LOT (shout out to life's best teacher @schoolofhardknocks).

#1 Don't use fluid from plastic bottles. Something is interacting with the fluid in plastic bottles. Since the volume of contaminate in a bottle is small and bottles aren't self destructing on the shelf, that means the interaction is limited, which means the substance causing the interaction is limited. This makes me suspect it is the residual oil on the bottle from the bottle manufacturing process. But that's none of my business, Toyota, thanks. Dollars to donuts you can get a refund on any plastic bottles you have. Word has been spread throughout Toyota/Lexus parts and service.

#2 Filter fluid. If you get in a bind and have to use fluid from a plastic bottle. Toyota recommended to dealers to strain it through a paint strainer (get those from a PPG or Sherman-Williams or the like). My advice is to 3-4 layers of cheese cloth. It's food-grade lint free. The fluid and the contaminate seem to have an affinity to cotton. I TRIED to push the contaminate past the cheese cloth and I could not. It's in almost any grocery store for a few dollars.

#2a Filter into a clear container. Glass is the best to ensure zero chemical interaction. Shine a light through it to be sure.

#2b Pour slowly. Don't overflow the strainer. The mesh on the strainer of the reservoir is tight enough to catch anything of size that would impact the system. I was in a rush initially (FML LOL OMG WTF) and fluid - and contaminate - went over the strainer and into the reservoir via the notches to secure the cap.

#3 Call Lexus customer service. If you have an Abnormal Oil Pressure for Pump fail, run the active test and still get the fault, get Lexus involved. 1-800-255-3987 (1-800-25-LEXUS). The tech manual says that if you have this fault and the active test doesn't resolve it, to replace the pump sub-assembly. The end. If you go beyond this, it's going to make it harder for you to get help from Lexus/Toyota. You have the best chance of getting help from them if they can see your vehicle, confirm you have a problem themselves, and see that the fluid caused the problem. I asked my parts manager at Lexus if I should call Toyota since I bought the fluid at a Toyota dealer, and after a long pause, he said he thought I would have better luck with Lexus.

Ok so let's say you are me and you are physically unable to give up no matter how bad it looks or how much you and everyone you know says you should give up.... Know that you are treading into territory in which Lexus can say "you did stuff that the tech manual does not say to do, we think you screwed this up, not our fluid." But, you are me, so continue...

#4 Flow fluid backwards. Here's your objective: to clear blockage from the pump sub-assembly inlet screen (photo thanks to @runnerxa on @Wes Gardner's thread his thread about the same issue on his 200). It's easy to tell inlet from outlet, because you can see the shadow of an imprint from the opening on the assembly to the reservoir inlet on the face of the pump sub-assembly.

Apply 12V to the pump motor in reverse polarity. This will run the pump backwards to force fluid in reverse to wash out the plugged inlet screen. You can do this in or out of the vehicle. It only needs to be for a second. There are several ounces of of fluid in/around the pump sub assembly and the volume occupied by the screen is probably 0.5mL (that's like 0.017 ounces) so there is plenty of fluid to get the job done. Be really damn careful not to short across the terminals of the pump motor and fry your pump motor (don't ask me how I know). Remove and clean out the reservoir (I cleaned out my reservoir with probably a whole can of brake parts cleaner and let it dry out), reassemble, reinstall, retest.

Here's a diagram of the pump connector plug. Note, if the test is NO GOOD, replace. Don't keep going. But...

Ok so you still can't clear the code, and you know you are hosed, but mamma didn't raise no quitter and a dead hero is the best hero, so you still keep trying...

#5 DO NOT disassemble the pump sub-assembly. There's no need for it, and you incur a lot of risk. Simply remove the pump sub assembly, clean off the inlet screen the best you can with a small implement and a shot of carb or brake cleaner will do the trick. The mesh filter on the inlet and the outlet of the pump sub-assembly, keeps everything clean - there will be nothing inside to need to clean out. See the photo on step 4 above.

Here's the deal: the inter-locking gears that push the fluid must be clocked to each other specifically in order to work. If you are like me and you just CAN'T not take something apart, mark where the gears touch each other when you take it apart and put them back in the same way. It's only the orientation of the gears to each other that matter. If the gears are not clocked together correctly, the pump will move a little fluid but cannot generate any pressure. Reassemble, reinstall, retest.

There is nothing else to do at this point. If you are a stubborn SOB like me, you can keep repeating these things until something goes wrong and you can't continue. The only thing to do is to get a new pump. Really all you need is a new pump assembly. Sorry. You should have stopped at #3. Chances are you could have talked them into a loaner, too. What a pity.

 

[Jcreme]

Wow significantly cheaper than what I was finding. That's good! Once you get your issues sorted let me know how it works out.

Worked out great! I have 14 gradations now from L to H. I forgot to mention that they were about $135 each, plus about $100 from Japan.

Probably you will need an accumulator too. They kind of all have the same life span. Well, let me just say it: my accumulator failed while I was bleeding my system after I got back on track (identified by large and persistent bubbles bleeding the left front and the systems showing accumulator pressure 0.0 MPa). SMH. $125 at IMPEX (plus shipping).

 

[lx200inAR]

Let me tell you the story about the day that @jLB saved Christmas! I didn't want to whine, but this whole situation was a lot worse than I initially described - mostly because we were due to depart on the Hunny's first real road trip on the 26th! All paid for. Nonrefundable. Thousands of dollars worth. And oh yeah, the kids had only one token Christmas gift because the trip was their gift. And there it was, bottomed out. All four corners around. OFF flashing on the dash. And since there are six of us, nothing else we had would cut it. And since "these unprecedented times," rentals (which were mostly not available) were stupid expensive.

I was sweating bullets. In fact, I was up in the middle of the night stressing, researching, memorizing the tech manual, when, a Christmas Miracle! I get a DM from @jLB "hey I think I've seen you around in your 80.. I think I live really close to you.. I have a couple of 100's with unused AHC pumps, I can help you out."

There are not emoji's to express how I felt at this point! Christmas was saved! Indeed jLB was practically walking distance away from me (how had we not met before?) and has a FINE collection of UZJ100's. After a couple of zips of the impact, a handshake, and monumental efforts on my part to avoid inappropriate affection for my new BFF forev-ah, the Hunny as standing a normal ride height by lunch the next day.

OK, so this is a tech forum, and I have learned a LOT (shout out to life's best teacher @schoolofhardknocks).

#1 Don't use fluid from plastic bottles. Something is interacting with the fluid in plastic bottles. Since the volume of contaminate in a bottle is small and bottles aren't self destructing on the shelf, that means the interaction is limited, which means the substance causing the interaction is limited. This makes me suspect it is the residual oil on the bottle from the bottle manufacturing process. But that's none of my business, Toyota, thanks. Dollars to donuts you can get a refund on any plastic bottles you have. Word has been spread throughout Toyota/Lexus parts and service.

#2 Filter fluid. If you get in a bind and have to use fluid from a plastic bottle. Toyota recommended to dealers to strain it through a paint strainer (get those from a PPG or Sherman-Williams or the like). My advice is to 3-4 layers of cheese cloth. It's food-grade lint free. The fluid and the contaminate seem to have an affinity to cotton. I TRIED to push the contaminate past the cheese cloth and I could not. It's in almost any grocery store for a few dollars.
View attachment 2871867
#2a Filter into a clear container. Glass is the best to ensure zero chemical interaction. Shine a light through it to be sure.

#2b Pour slowly. Don't overflow the strainer. The mesh on the strainer of the reservoir is tight enough to catch anything of size that would impact the system. I was in a rush initially (FML LOL OMG WTF) and fluid - and contaminate - went over the strainer and into the reservoir via the notches to secure the cap.

#3 Call Lexus customer service. If you have an Abnormal Oil Pressure for Pump fail, run the active test and still get the fault, get Lexus involved. 1-800-255-3987 (1-800-25-LEXUS). The tech manual says that if you have this fault and the active test doesn't resolve it, to replace the pump sub-assembly. The end. If you go beyond this, it's going to make it harder for you to get help from Lexus/Toyota. You have the best chance of getting help from them if they can see your vehicle, confirm you have a problem themselves, and see that the fluid caused the problem. I asked my parts manager at Lexus if I should call Toyota since I bought the fluid at a Toyota dealer, and after a long pause, he said he thought I would have better luck with Lexus.

Ok so let's say you are me and you are physically unable to give up no matter how bad it looks or how much you and everyone you know says you should give up.... Know that you are treading into territory in which Lexus can say "you did stuff that the tech manual does not say to do, we think you screwed this up, not our fluid." But, you are me, so continue...

#4 Flow fluid backwards. If you are lucky enough to be at any ride height above L, drop it into L. This will flow clean fluids in the lines through the pump and through the mesh filters on the pump sub-assembly and push contaminate into the reservoir. Then pull the whole AHC assembly, remove the reservoir, and dump out the fluid. The contaminate is very close in density to the fluid, so it does not settle out very fast. I cleaned out my reservoir with probably a whole can of brake parts cleaner and let it dry out. Reassemble, reinstall, retest.

Here's your objective: to clear blockage from the pump sub-assembly inlet screen (photo thanks to @runnerxa on @Wes Gardner's thread his thread about the same issue on his 200). It's easy to tell inlet from outlet, because you can see the shadow of an imprint from the opening on the assembly to the reservoir inlet on the face of the pump sub-assembly.

View attachment 2871881

If you are still stuck, but can't quit, admit you are unhealthily attracted to problems and continue messing with it until you break it good...

#4a Apply 12V to the pump motor in reverse polarity. This will run the pump backwards to force fluid in reverse to wash out the plugged inlet screen. You can do this in or out of the vehicle. It only needs to be for a second. There are several ounces of of fluid in/around the pump sub assembly and the volume occupied by the screen is probably 0.5mL (that's like 0.017 ounces) so there is plenty of fluid to get the job done. Be really damn careful not to short across the terminals of the pump motor and fry your pump motor (don't ask me how I know). Remove and clean out the reservoir, reassemble, reinstall, retest.

Here's a diagram of the pump connector plug. Note, if the test is NO GOOD, replace. Don't keep going. But...
View attachment 2871884

Ok so you still can't clear the code, and you know you are hosed, but mamma didn't raise no quitter and a dead hero is the best hero, so you still keep trying...

#5 DO NOT disassemble the pump sub-assembly. There's no need for it, and you incur a lot of risk. Simply remove the pump sub assembly, clean off the inlet screen the best you can with a small implement and a shot of carb or brake cleaner will do the trick. The mesh filter on the inlet and the outlet of the pump sub-assembly, keeps everything clean - there will be nothing inside to need to clean out. See the photo on step 4 above.

Here's the deal: the inter-locking gears that push the fluid must be clocked to each other specifically in order to work. If you are like me and you just CAN'T not take something apart, mark where the gears touch each other when you take it apart and put them back in the same way. It's only the orientation of the gears to each other that matter. If the gears are not clocked together correctly, the pump will move a little fluid but cannot generate any pressure. Reassemble, reinstall, retest.

There is nothing else to do at this point. If you are a stubborn SOB like me, you can keep repeating these things until something goes wrong and you can't continue. The only thing to do is to get a new pump. Really all you need is a new pump assembly. Sorry. You should have stopped at #3. Chances are you could have talked them into a loaner, too. What a pity.

Awesome breakdown. Just so I understand. You were able to revive your pump by backing fluid back through it and cleaning up the mesh screens? It seems from the beginning of the post that you used a spare pump from JLB. Hopefully this won't be an issue anymore now that the root cause has been found. Congrats on getting it all resolved and good luck on your trip.

 

[Jcreme]

Awesome breakdown. Just so I understand. You were able to revive your pump by backing fluid back through it and cleaning up the mesh screens? It seems from the beginning of the post that you used a spare pump from JLB. Hopefully this won't be an issue anymore now that the root cause has been found. Congrats on getting it all resolved and good luck on your trip.

No I shorted out my motor before I figured out that I had reassembled the pump sub assembly without noting the correct clocking position. The only hope of resolving that situation would have been to move the gears one tooth at a time, reassemble, reinstall, test, remove and repeat until the pump created pressure.

I thought I had done that because I turned the pump manually and it generated flow, but without putting it into a closed system, you can’t test that it makes pressure, which is key.

So main lesson: you can take apart the AHC Pump assembly, but don’t take apart the pump sub-assembly. (The actual mechanical pump about the size of half a baseball).

The steps I’ve outlined will resolve an Abmormal Pump Pressure code due to clogging with gelled up fluid.

The gel is actually really easy to get rid of. The problem is the info about the pump assembly is too scant. All that is needed is to clear the inlet screen and filter the fluid.

Nonetheless, one should call Lexus and hand them the mess they made. Unless you absolutely have to have it fixed now like I did.

 

[lx200inAR]

No I shorted out my motor before I figured out that I had reassembled the pump sub assembly without noting the correct clocking position. The only hope of resolving that situation would have been to move the gears one tooth at a time, reassemble, reinstall, test, remove and repeat until the pump created pressure.

I thought I had done that because I turned the pump manually and it generated flow, but without putting it into a closed system, you can’t test that it makes pressure, which is key.

So main lesson: you can take apart the AHC Pump assembly, but don’t take apart the pump sub-assembly. (The actual mechanical pump about the size of half a baseball).

The steps I’ve outlined will resolve an Abmormal Pump Pressure code due to clogging with gelled up fluid.

The gel is actually really easy to get rid of. The problem is the info about the pump assembly is too scant. All that is needed is to clear the inlet screen and filter the fluid.

Nonetheless, one should call Lexus and hand them the mess they made. Unless you absolutely have to have it fixed now like I did.

Thanks. That seems to be what the two guys on the 200 forum who ended up in same position thought. They both went too far in breaking down the pump and couldn't get it to make pressure after putting it back together. Both felt if they hadn't taken the pump apart and had just cleaned the screens they would have been okay.

 

[suprarx7nut]

Really awesome summary. Nice work and good on you for pushing through the details to the end.

What a crazy situation. I still have a bunch of plastic bottles I need to test. I'll probably record opening each one and if a contaminated one pops up, I'll hit up Toyota/Lexus NA on instagram. I think once this gets some notoriety they'll be more likely to go out of their way to put out a TSB or recall or something of meaning, aside from refunding those who know to ask for it.

 

[flintknapper]

I wouldn't even use 'strained' fluid that had gelled. Perhaps it is 'stable' but who knows. For the other part to have gelled it had to have happened chemically at the molecular level. Some amount of cross-linking/bonding of the molecules happened. You can't strain at the molecular level with cheesecloth. The only unknown is whether the 'gel' is a container/petroleum born substance (separate from the fluid), or the fluid itself.

My 'guess' would be the fluid interacts with the container....producing some amount of gel and not the other way around. Meaning removing the gel would render usable fluid...but we don't know that.

 

[jLB]

Let me tell you the story about the day that @jLB saved Christmas! I didn't want to whine, but this whole situation was a lot worse than I initially described - mostly because we were due to depart on the Hunny's first real road trip on the 26th! All paid for. Nonrefundable. Thousands of dollars worth. And oh yeah, the kids had only one token Christmas gift because the trip was their gift. And there it was, bottomed out. All four corners around. OFF flashing on the dash. And since there are six of us, nothing else we had would cut it. And since "these unprecedented times," rentals (which were mostly not available) were stupid expensive.

I was sweating bullets. In fact, I was up in the middle of the night stressing, researching, memorizing the tech manual, when, a Christmas Miracle! I get a DM from @jLB "hey I think I've seen you around in your 80.. I think I live really close to you.. I have a couple of 100's with unused AHC pumps, I can help you out."

There are not emoji's to express how I felt at this point! Christmas was saved! Indeed jLB was practically walking distance away from me (how had we not met before?) and has a FINE collection of UZJ100's. After a couple of zips of the impact, a handshake, and monumental efforts on my part to avoid inappropriate affection for my new BFF forev-ah, the Hunny as standing a normal ride height by lunch the next day.

OK, so this is a tech forum, and I have learned a LOT (shout out to life's best teacher @schoolofhardknocks).

#1 Don't use fluid from plastic bottles. Something is interacting with the fluid in plastic bottles. Since the volume of contaminate in a bottle is small and bottles aren't self destructing on the shelf, that means the interaction is limited, which means the substance causing the interaction is limited. This makes me suspect it is the residual oil on the bottle from the bottle manufacturing process. But that's none of my business, Toyota, thanks. Dollars to donuts you can get a refund on any plastic bottles you have. Word has been spread throughout Toyota/Lexus parts and service.

#2 Filter fluid. If you get in a bind and have to use fluid from a plastic bottle. Toyota recommended to dealers to strain it through a paint strainer (get those from a PPG or Sherman-Williams or the like). My advice is to 3-4 layers of cheese cloth. It's food-grade lint free. The fluid and the contaminate seem to have an affinity to cotton. I TRIED to push the contaminate past the cheese cloth and I could not. It's in almost any grocery store for a few dollars.
View attachment 2871867
#2a Filter into a clear container. Glass is the best to ensure zero chemical interaction. Shine a light through it to be sure.

#2b Pour slowly. Don't overflow the strainer. The mesh on the strainer of the reservoir is tight enough to catch anything of size that would impact the system. I was in a rush initially (FML LOL OMG WTF) and fluid - and contaminate - went over the strainer and into the reservoir via the notches to secure the cap.

#3 Call Lexus customer service. If you have an Abnormal Oil Pressure for Pump fail, run the active test and still get the fault, get Lexus involved. 1-800-255-3987 (1-800-25-LEXUS). The tech manual says that if you have this fault and the active test doesn't resolve it, to replace the pump sub-assembly. The end. If you go beyond this, it's going to make it harder for you to get help from Lexus/Toyota. You have the best chance of getting help from them if they can see your vehicle, confirm you have a problem themselves, and see that the fluid caused the problem. I asked my parts manager at Lexus if I should call Toyota since I bought the fluid at a Toyota dealer, and after a long pause, he said he thought I would have better luck with Lexus.

Ok so let's say you are me and you are physically unable to give up no matter how bad it looks or how much you and everyone you know says you should give up.... Know that you are treading into territory in which Lexus can say "you did stuff that the tech manual does not say to do, we think you screwed this up, not our fluid." But, you are me, so continue...

#4 Flow fluid backwards. If you are lucky enough to be at any ride height above L, drop it into L. This will flow clean fluids in the lines through the pump and through the mesh filters on the pump sub-assembly and push contaminate into the reservoir. Then pull the whole AHC assembly, remove the reservoir, and dump out the fluid. The contaminate is very close in density to the fluid, so it does not settle out very fast. I cleaned out my reservoir with probably a whole can of brake parts cleaner and let it dry out. Reassemble, reinstall, retest.

Here's your objective: to clear blockage from the pump sub-assembly inlet screen (photo thanks to @runnerxa on @Wes Gardner's thread his thread about the same issue on his 200). It's easy to tell inlet from outlet, because you can see the shadow of an imprint from the opening on the assembly to the reservoir inlet on the face of the pump sub-assembly.

View attachment 2871881

If you are still stuck, but can't quit, admit you are unhealthily attracted to problems and continue messing with it until you break it good...

#4a Apply 12V to the pump motor in reverse polarity. This will run the pump backwards to force fluid in reverse to wash out the plugged inlet screen. You can do this in or out of the vehicle. It only needs to be for a second. There are several ounces of of fluid in/around the pump sub assembly and the volume occupied by the screen is probably 0.5mL (that's like 0.017 ounces) so there is plenty of fluid to get the job done. Be really damn careful not to short across the terminals of the pump motor and fry your pump motor (don't ask me how I know). Remove and clean out the reservoir, reassemble, reinstall, retest.

Here's a diagram of the pump connector plug. Note, if the test is NO GOOD, replace. Don't keep going. But...
View attachment 2871884

Ok so you still can't clear the code, and you know you are hosed, but mamma didn't raise no quitter and a dead hero is the best hero, so you still keep trying...

#5 DO NOT disassemble the pump sub-assembly. There's no need for it, and you incur a lot of risk. Simply remove the pump sub assembly, clean off the inlet screen the best you can with a small implement and a shot of carb or brake cleaner will do the trick. The mesh filter on the inlet and the outlet of the pump sub-assembly, keeps everything clean - there will be nothing inside to need to clean out. See the photo on step 4 above.

Here's the deal: the inter-locking gears that push the fluid must be clocked to each other specifically in order to work. If you are like me and you just CAN'T not take something apart, mark where the gears touch each other when you take it apart and put them back in the same way. It's only the orientation of the gears to each other that matter. If the gears are not clocked together correctly, the pump will move a little fluid but cannot generate any pressure. Reassemble, reinstall, retest.

There is nothing else to do at this point. If you are a stubborn SOB like me, you can keep repeating these things until something goes wrong and you can't continue. The only thing to do is to get a new pump. Really all you need is a new pump assembly. Sorry. You should have stopped at #3. Chances are you could have talked them into a loaner, too. What a pity.

It was a pleasure to meet you, and I’m glad I was able to help!

(Merry Christmas!)

 

[MarkTR]

I drained and filtered (very fine paint strainer) each of the four bottles I bought from McGeorge a few months back.

All four had no gell--just light red fluid.

I am now storing the fluid in glass Ball jars.

I guess I dodged a bullet- but I am not going to flush my AHC system until we find out more info if it is the fluid itself that forms the gell, or if it is the fluid's interaction with the plastic bottles.

 

[IndroCruise]

#4 Flow fluid backwards. If you are lucky enough to be at any ride height above L, drop it into L. This will flow clean fluids in the lines through the pump and through the mesh filters on the pump sub-assembly and push contaminate into the reservoir.

All good and helpful insights in post #22. Just to be clear, suggest be aware that when lowering the vehicle, the Return Valve sends fluid from Shock Absorbers, 'globes' and lines directly to the AHC Tank, bypassing the AHC Pump. The fluid does not flow back through the pump or its strainers when lowering the vehicle.

Suggest also that the outlet strainer be cleared as well as the inlet strainer if gel deposits or other blockage is suspected in the pump.

Hydraulic circuit when lowering vehicle:

Return Valve detail:

 

[Jcreme]

All good and helpful insights in post #22. Just to be clear, suggest be aware that when lowering the vehicle, the Return Valve sends fluid from Shock Absorbers, 'globes' and lines directly to the AHC Tank, bypassing the AHC Pump. The fluid does not flow back through the pump or its strainers when lowering the vehicle.

Suggest also that the outlet strainer be cleared as well as the inlet strainer if gel deposits or other blockage is suspected in the pump.

Thank you so much! I should have known that! #facepalm Let me correct post 22.

Had a great trip to Breckenridge BTW the AHC performed flawlessly. Rode like a limo on the highway and climbed the snowy unpaved road (up 1300 ft every day) like a land cruiser

 

[J Jamm]

@Jcreme Was it easy to remove and clean the reservoir? Can the reservoir be removed by itself without pulling off the pump?

 

[Jcreme]

@Jcreme Was it easy to remove and clean the reservoir? Can the reservoir be removed by itself without pulling off the pump?

Hmmm I pulled the whole thing, which is pretty easy, but I needed the pump out. If your only interest is the reservoir, it might be easier to just remove the reservoir, but messy. It is held on only by two 10mm bolts, one in the front and one in the back. If you can get to the rear one, it would be pretty easy. The only thing is it will be near impossible to get it off without spilling AHC fluid everywhere. you will need to empty it completely, down to the hole in the bottom leading to the pump assembly. AHC fluid is hard to clean up.

The one thing that bothered me about cleaning the reservoir was that the accumulation inside had formed like a flaky film, and I was really worried about having flakes inside that I had loosened from the side or bottom staying behind. After mine was clean, I rinsed it three times with brake cleaner.

BTW brake cleaner does not seem to dissolve AHC fluid. Nor does acetone or alcohol. You might try carb cleaner - I didn't have any on-hand. Just put a drop of AHC fluid on cardboard and then shoot it with carb cleaner and see if the AHC evaporates with the carb cleaner. Cotton rags are great for cleaning up AHC fluid, but that's no help inside the reservoir.

 

[IndroCruise]

@Jcreme Was it easy to remove and clean the reservoir? Can the reservoir be removed by itself without pulling off the pump?

@Jcreme has covered it -- a few more pics showing tank removal can be found here:

AHC pump removal with pics - https://forum.ih8mud.com/threads/ahc-pump-removal-with-pics.1227554/#post-13401739

If really concerned, a new clean AHC Tank could be considered -- Part No. 48930-60010 (Partsouq: USD83.83 plus shipping, local source may be better).

More details on the AHC Pump itself, including pictures of the tiny internal strainers on the input and output sides of the actual gear pump can be found at the thread references within this post:

Is This the End for My AHC Pump? - https://forum.ih8mud.com/threads/is-this-the-end-for-my-ahc-pump.1241947/#post-13665935