AHC system bleeding 5th valve.

[Raj]

On Monday this week, I did bleed AHC system on my car. Got about 1.5 litres out from 4 bleed valves. The fluid was not pink but was brownish. Since I had about 4 litres left out from the new can, today I repeated the process again for 4 bleeders. Actually, the fluid in the system was not AHC fluid, it was brake fluid. This pic was after 4th bleed and it was foaming with water. I decided to repeat the process of filling 1 litre, bleed 1 litre from 4 bleeders and refill.

In the instructions I have, it was clearly mentioned not to touch the 5th bleeder. Any suggestions if we can or can not touch the 5th bleeder.? Will handling and ride become even better if I bleed 5th one?
Can we remove all fluid by filling, bleeding 5 litres of the fluid? I was thinking of buying another 5 litres and just repeating the process until I use up all 10 litres. Will that ensure no old brake fluid is left out in the system?

 

[guyc]

Has it previously been filled up with brake fluid?

It should be filled up with this stuff.

5 Litres Genuine Toyota AHC Suspension Fluid - [Leaving Land Cruiser Club]

Just to add to this, looking at the Roughtrax website it suggests using brake fluid will erode the polymer seals in the AHC system. That might be garbage but I don't think they have anything to gain by saying it.

 

[Raj]

brake fluid?

When the AHC failed, last year, the used car guy from whom I got the car repaired it and gave it back to me under warranty. He might ve filled up that fluid. He told me suspension fluid is very expensive and he purchased it etc etc. Its not that expensive and if someone says such stories, its usually to cover up something.

 

[Tractionman]

What makes you think it's brake fluid Raj ?

 

[guyc]

It's about £18 per litre so of the fluids you chuck in your truck, it's probably the most expensive in terms of £ per litre.

From some of the pictures on IH8MUD of AHC fluid, that looks pretty clean so it possibly was changed by the garage. It's also the right colour for AHC fluid.

 

[Raj]

brake fluid

on Monday when i started this bleeding process fluid colour was nowhere near pink. Somewhere I read brake fluid can be used as an alternative so thought it might be that.
Yesterday when I took the pic I already added 3 liters of Toyota AHC into it. Today I repeated the process and did run more than a litre into it. Today's colour was better than yesterday but not exactly like the new one. I am left out with approx 600 ml now.
Now I won't let my OCD take over and I will wind up this project or try to bleed the accumulator valve (the 5th one) tomorrow if I get a nightmare

It's about £18

Agree its more expensive than diff oil I changed recently. I didn't think this way, I was only thinking as cost per 5 years but that's not how the garage will think.

 

[Raj]

I didn't touch the 5th bleeder valve (its called the accumulator?). Yesterday I probably didn't close the bleeder valves properly so there was a slight drip. Tightened them and closed the project. Planning to take up this project next year again with a new procedure I found on the net and I will drain the 5th one as well. As of yesterday, I am 80% satisfied with the flow of fluid and colour coming out of 4 bleeder valves so winded up this learning/maintenance project.

The front ones are easy and can be done with every oil change if I wish. The rear ones are difficult to reach. Jon did a trick and bent the 10mm spanner and used but I couldn't bend it so used a combination of tools I have. The only disadvantage is that I cant attach a tube to the bleeder to see what's coming out but I am sure all air is gone as I ran over more than 4 liters oil and bled each side many times. Oil spills everywhere so I used some broad tin cap from my kid's toy box to catch all the oil.
I did all the procedures with the car at normal height and after the procedure, I pressed it to high, then to normal, low, and high again and let it run for a few mins, and switched off the engine. I filled the AHC fluid to max level and winded up the process.

Video of change in fluid level after the procedure. I removed the spare tire and tied a flash light in that place.

 

[pugwash]

Nice RaJ- great job. Bet the suspension will feel that little bit softer now

It's a lovely truck- i was lucky enough to take it for a drive last week! Thanks Raj

 

[Raj]

Finally did the AHC accumulator bleed/flush. This was easier than I thought. Just opened the bleeder until all the fluid was drained, added about a litre into the AHC reservoir tank and switched on the car and cycled through L,N,H settings. At first opening bleeder opened suddenly and I spilled oil everywhere but later it was fine.

 

[Brett]

Finally did the AHC accumulator bleed/flush. This was easier than I thought. Just opened the bleeder until all the fluid was drained, added about a litre into the AHC reservoir tank and switched on the car and cycled through L,N,H settings. At first opening bleeder opened suddenly and I spilled oil everywhere but later it was fine.

Hey Raj, did you notice any improvement in ride quality after replacing the AHC fluid, I think mine needs doing, it seems a bit bumpier than when I first bought the Cruiser.

 

[Raj]

bit bumpier

Hi Brett. There was a slight difference in the ride. I didn't even notice if the ride was bumpy. In one of the club meets Jon tested the car and told me it feels a bit bumpy and needed air bleeding so I did it.
There was a lot of air trapped. I could see a lot of foamy fluid coming out from each side. So I repeated the process until I was able to see clear fluid flowing out from bleeders and ended up using all the fluid I bought.

 

[Brett]

Thanks for replying Raj, I'll give it a go, I'm hoping the accumulators don't need replacing also, but I'll try the oil flush first.

Do you have any good links to guides?

 

[Raj]

guides?

I used these two as SOPs and did some extra as I felt appropriate while under the car.

 

[Raj]

accumulators

I read somewhere that if those globes are starting to worn out, they will create more air bubbles. I will bleed AHC again this summer just to see how the fluid is after about 1 year.
Somewhere else I also read that its best practice to bleed this every year but not sure about that as there are many such things and I will end up working on the car all the time or spending a lot for garages. I am already under the car most of the time just for curiosity looking at things and most of my friends think its always under repair. This is spoiling the reputation of LandCruiser

 

[Brett]

Thanks Raj, much appreciated.

This is spoiling the reputation of LandCruiser

 

[Raj]

Also check ihmud site. In 200 section there is lot on AHC bleeding as Lexus LX570 in US has the same AHC system we have on our cars.

 

[Raj]

g

good links to guides?

LX570 AHC “Basics” - Added as sticky thread for AHC Issues

https://forum.ih8mud.com/threads/lx570-ahc-basics-added-as-sticky-thread-for-ahc-issues.1053154/post-14807577 I'm answering my own question. Yes. The 2-digit code in the display (13) corresponded with the TYT II tool (C1713). Sensor replaced. All good. So, if you don't have a fancy code...

forum.ih8mud.com

Check above thread. The whole thread is dedicated to AHC on 200 series.

 

[Brett]

Thanks Raj, I'll have a read, I've bought the fluid, just waiting for a good weather day at the weekend.