Which power steering stop leak to use?

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HomersCanyonero

HomersCanyonero

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I took it to a couple of independent mechanics and it's not obvious where it's leaking from. I use ATF for the power steering. I want to try a stop leak, but do I put "Lucas Power Steering Leak Stop?"

Or do I have to use a transmission stop leak made for ATF oil?

Or does it matter?

Thanks in advance...
 
I would doubt either one is going to do a lot to help you. Where is it leaking from? Commonly the leak comes from the steering pump or the low pressure hose under the reservoir. Resealing the pump and replacing the low pressure hose are both pretty easy.
 
I used the Lucas fluid for a while. I think it did slow down the leak (back of pump), but then I think I read somewhere that you shouldn't use these types of products as they will swell up all your seals which can lead to further problems. After I stopped using the Lucas fluid my leak did stop though after a while.
 
FWIW, mine was leaking into the engine oil past the internal seals in the pump. Replacing the block-to-pump o-ring did not help. So if you're losing ATF from the PS system but have no external signs of leakage, then check your engine oil level and color. This only applies to 1FZ trucks. Just my 2 cents.
 
I have plenty of external leaks! It looks clean from the top of the engine, but it's a mess from under (see photo taken from underneath truck). I just can't tell exactly where it's leaking from.
PowerSteeringLeak.webp
 
BigAxeJack said:
FWIW, mine was leaking into the engine oil past the internal seals in the pump. Replacing the block-to-pump o-ring did not help. So if you're losing ATF from the PS system but have no external signs of leakage, then check your engine oil level and color. This only applies to 1FZ trucks. Just my 2 cents.
Click to expand...
^This was my case as well. Ordered up the rebuild kit, put it together and re-installed. My high and low pressure lines were fine, however my friends 80 wasn't so lucky, he had to replace both as well as the rebuild.
 
I might try the rebuild kit for the pump. I just can't tell exactly where the leak is. I'm showing the return hose which I think the low pressure hose.
PowerSteeringLeak4.webp

PowerSteeringDiagram.webp
 
Be sure to replace the gasket(s) in the picture. I believe it is a copper banjo style, and obviously the o-ring. There is a good write up on the job in the FAQ. Or search for the thread made by "gnob". Acutally think there is couple of them out there. The high pressure line is sorta spendy IIRC.
 
Brake fluid! Yep, in the trade we have been using if for years, makes the car stop, takes off your paint AND seals leaking power steering pumps and boxes. One egg cup full will sort it, pour it in the reservoir and drive around for a week or two, if it continuous to leak then fix it...what have you got to lose? Does not fix hoses!

regards

Dave
 
Add some ultraviolet dye to the fluid. Get a black light and you will know right where its coming from.
 
I wouldn't try to use a stop leak product for a permanent fix BUT for a temporary or in a pinch solution there are trans stop leak products, just in case you want something "formulated" to mix with ATF.
 
Dave: I saw other posts where you recommend adding an egg-full cup of brake fluid to the power steering when it's leaking ATF. The reasoning was that ATF doesn't have anti-leak additives, but regular power steering fluid does. It sounds like you have been trying this, but has anyone else tried it in the USA?

It's interesting that we freak out when someone tops off the brake reservoir with power steering fluid. All hell breaks loose from what I understand. Is the reverse (adding brake fluid to the power steering reservoir that uses ATF) not true?

Scrowley: Thanks for the tip on the ultraviolet dye. This sounds like a good way to figure out where the leak is at.
 
The reseal kit is less than $20 from rockauto, you can get hose buy the foot from any parts store, atf is cheap at walmart. You can probably pull it, re seal, and replace all low pressure lines for less than $60

Also, to answer your original question, if it has ATF then use the Lucas atf stop leak. I used this on my wifes truck for about a year. It will slow the leak but not stop it.
 
I had a drip that looked like that top photo. It's the oring that seals the rear of the pump (opposite side from the pump shaft end). You can buy a pump reseal kit to repair it. When I bought my 80, it came with a red drip and a reservoir full of Lucas Stop Leak. It always dripped and i kept topping it off with Lucas until one cold morning the low pressure line blew. After replacing the hose, I refilled with ATF and the pump drip has slowed dramatically ( still need to reseal the pump).
 
I understand the doubts about using brake fluid but think about what it usually has to put up with, think how many 'leaking brake calliper' threads you see.....exactly. Very rare indeed, the brake fluid allows the seals to swell ever so slightly, having 'been in the trade' for 40+ years I can assure you nothing but good comes from it. If it does not work then fine repair it.

regards

Dave
 
Dave,

Thanks for the advise. If the problem is the seals in the pump, what would be the difference between adding an egg-cup full of brake fluid and adding the same amount of ATF stop leak?

Also, this doesn't fix if the problem is in the high pressure or low pressure hoses. I still don't know what the problem is...at least not yet.

Thanks
 
The difference is ATF fluid tends to maintain the seals over years, and when the trans fails it is normally a rebuild and we know how much warning you do NOT get when an auto fails, brake fluid will make the seals expand fairly quickly i.e. under two weeks driving. High pressure hoses tend to seep around the connections so check they are tight first, or they could be leaking from the 'swage' where the rubber is clamped to the steel. I tend to wash everything down in petrol (yeh I know, danger/solvent/blah blah) but old habits die hard. Once it all washed down and allowed to dry any leaks will be obvious.

regards

Dave
 
Last edited:
Wrong approach.
If your savvy take it off and rebuild and replace low pressure hose while your at it (less than $50).
Your driving a LC not a Kia.
If your scared of rebuild (little tedious) then buy an already rebuilt one and have it replaced.
They leak at the seal on the back.
Make sure you get new Banjo fitting and new Block to Pump O-ring. Rest of rebuild parts are in kit. I recommend the Gates kit and you can get on Rock Auto or at your local auot parts shop.
 
There's always one! A leaking seal is a leaking seal, the man asked for a sealant solution, I gave him one!

I can see you now at the side of the road with a puncture, your spare is also flat and you have a can of tyre sealer/inflator, ooooh it's pissing down with rain and I am twenty miles from home I cannot use this repair kit on my Land Cruiser as it is the 'wrong approach'....no wait....it's ok I went to work in the Kia THANK GOD....ppssssssttt!!

Give me a break pleeeeease!

regards

Dave
 
POWER WASH it. Dont guess. Maybe use a little brake cleaner-get it clean and you will see the leak. Lots of PS leaks you can make leak more by holding the steering wheel hard to one side-have a helper do that while you watch it.
. Maybe just a loose fitting. WAsh the motor on a regular basis and you will see any leak (external).
 
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