Penetrating Oil

[Bod]

I am having trouble removing Stainless steel screws from cast aluminium Currently using Mouse Milk Penetrating Oil but no movement.Any suggestions would be welcome.
Jeff

[DaveW]

I dont know much about removing them, but i know its called "bimetalic galvinization" and the two metals essentially become "welded".

Hope fully some one can help you with a solution.
I had a ss bolt in an aluminium bracket that literally tore the thread out of the bracket when trying to remove it.

[Silversmith]

you might ck out prolong.com They have very good products. Engine additive, trans additive, penetrating oils. I've been using them for years with very good results.

[damage]

Pour hot water on to it to heat it up

[dhs.buckley]

get the oxy torch on to it, but it will probably tear the alloy thread out anyway you do it

[bobcowan]

The best penetrating oil for something like that is a 50:50 mix of acetone and auto trans fluid.

But, you'll probably end up destroying the thread in that aluminum component. Use a Thread-sert or Time-Sert for repair.

[Ralphy]

The thermal expansion of aluminum should be greater than stainless. As said, "get the oxy torch on to it"

Ralphy

[07cob]

Jeff

I the part accessible? The only success I have had removing stuck bolts is setting up a jig and drilling them out. Get close enough to the thread and then collapse the bolt leaving the female thread in tact.

Geof

[kyleb]

Bummer!!
Unfortunately if mouse milk doesn't do it nothing penetrating oil wise Nothing will.
Looks like heat is the go for a start.
If that doesn't work drilling will be really difficult with the stainless because it work hardens real easy.
Take your time with a new good quality drill, oil and slow speed.
If you have good access try drilling dead centre if you can with a drill the I.D of the thread then sometimes you can then wind the thread piece left over out with pliers.
Good luck

[PeterAllen]

Depending on the replacement cost of the component you might want to consider spark erosion.

Spark erosion removal of broken thread in turbo charger - YouTube

[stephen low]

I struck a similar issue once trying to remove a head off a laser with the head bolts seized.

Application of heat and shock hitting the end of the bolts eventually freed them all.

Was able to set up a ring spanner and would work the bolt in both directions though a fraction at a time until the whole thread freed up. Got all the bolts out with no damage to the alloy threads that I was aware of.

Worst case though is as suggested, carefully drill out the centre until you can use an easy-out to reverse out the remainder of the thread. If you are down to this then thread damage is a likelihood but correctable too.

Good luck.

Steve

[Bod]

Thanks Guys
It looks like I have a few more options
Jeff

[Bod]

Thanks Guys
It looks like I have a few more options
Jeff

[Mdman352]

Use Kroil oil. Best penetrate ever made.

Penetrating-Lubricating Oils

[sllib]

x2 on the Kroil. Also, you might consider getting a impact driver (anyone who works on bikes knows what that is) but, instead of setting it to loosen, set it to tighten and SLIGHTLY tighten the screw, then loosen it. I've used this method with great sucess in the past with no damage to threads.
Bill

[Donunder]

Showing my age again but I used to use stuff called GE5 super penetrant, made, strangely enough, by the GE5 chemical company in Melbourne. It always seemed to do the trick.

It came in 10 fl oz cans. I don't know whether it's still available (it's probably been declared toxic or something) but I still have a quarter full can on my shelf....

[streetrod1927]

Try Gibbs Oil. It worked for me on a number frozen bolt/nut issues.