So after removing the bumper and various panels to get to the pump, I decided to take it to a trusted local shop to get a professional diagnosis. If it turn out to be a bad pump, I’m going to have to drive it as is for a few months. The pump is crazy expensive! Fingers crossed, I’m still hoping it’s just a clog between the tank and the pump.
I did a quick check, and didn't see anything about bench bleeding.
So I picked up the truck from the mechanic...who had no idea what was causing the problem. So I’ve brought it home and will re attack the problem myself in the morning.
the idea that the pump needs to be primed is promising. Does anyone know how I would go about this? I haven’t found anything in the repair manuals thus far.
I could simply drain the system and pull the pump for inspection, but I would end up having to reprime it after reinstalling anyway, so priming and testing seems the logical next move. I’m all ears on suggestions on this. I did a bit of reading on it and noted that pumps sometimes lose prime because of blockages in the inlet filter. Which sounds very plausible.
The mechanic rebled the system several times it appears. The front left tire is buried in the wheel well and it drove so badly on the way home I started feeling motion sickness. I will need to reintroduce fluid into the front collectors to remedy this. I’m assuming I’ll have to pump some in via the bleeders, which should be fun with only a manual pump. That’s my last gasp plan at the end of day Thursday. I need it driveable by then, or I will have to take a car on my weekend trip into the hills.
ps.Since I know more than a few of you have ripped out your ahc,(I think it’s a great system personally), does anyone have a functioning pump they would be willing to part with? PM me if you do!
Do you know the guys name? What dealership? I would love to talk to him. My first couple ideas today have had limited success.The "not self priming" is what I was told by another master Lexus mechanic - the one that ended up fixing my LX. He explicitly told me that the pump HAS to be primed manually, otherwise it will burn out, like what the first mechanic did.
My pump is still attached, I can remove it tonight after work. Any tips on removal?
Do you know the guys name? What dealership? I would love to talk to him. My first couple ideas today have had limited success.
My current plan is to start cracking hose fittings on the pump. This should theoretically allow any air in the pump to be replaced with oil. I’m going to mark my tank fluid level first, so I can see any fluid level changes.
Does anyone have fender measurements for the truck in low and normal modes? I just measured mine and got the following values. Truck is technically in low, but it’s actually below that I think.
FR 30 3/4
FL (passenger) 31
RR 32 1/8
RL (passenger) 32 3/4
I removed the pump, it has like 200k miles on it but was working fine before I disabled the system. There was still fluid in the reservoir, but I poured most of it out the fill tube. The strainer also fell into my used oil bucket.the manual shows removing both rear mud flaps, and the bumper cover. All easy, but don’t forget to unplug the rear sensors from the bumper. You also have to remove the luggage compartment cover protector 1 and the Fuel tank filler pipe protector. These were easy except for the 6 square plugs, which I had to cut to remove. I ordered a bag of replacements on amazon that should arrive today. 4 on the fuel cover, 2 on the luggage. I was able to get the luggage ones out.
You will need to discharge the fluid from the 5th accumulator to depressurization the system.
It all sounds more complicated than it is. Other than an hour wasted fighting the square plugs, it took less than an hour to remove all the pieces.
the annoying plugs in question:
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