Rust Penetrant Recomendations

[Scooby074]

I have to remove the exhaust manifolds on a 2003 F150 to repair an annoying exhaust leak for inspection,and the manifold studs are extremely rusted. This has me thinking about rust penetrants.

What rust penetrants do you recommend in general?

Ive had the best results with Aerokroil however i no longer have access to it and ordering a case by mail order from Canada is $$$. Not to mention the delivery time involved.

Ive tried Liquid Wrench, WD 40, Lloyds and the Bowmans and the like, but havent had much luck so im open to suggestions.

Can anybody recommend Zep's 45 or Twister?

On a related note, do any members here know where AeroKroil can be bought by the can in Nova Scotia?

Does anybody know of a head to head scientific test done that tested penetrant effectiveness?

 

[Sackett2]

at work (a Subaru shop) the best i have seen is GM penetrate. works very good, better than most anything I know of.
That being said, heat may be your only solution to your exhaust studs. I have the same issue with my truck (but I don't have inspections ) Had the engine apart 40,000 miles ago, but don't want to pull them off again. so for now it will leak.

 

[J_J]

There is a test for the best penetrating oil somewhere on the Internet. I believe it had equal parts of ATF and Acetone, and maybe kerosene. When you mix it, you have to use it as the Acetone will evaporate. So I would just make small amounts.

 

[mrutkaus]

Used various of these fluids to loosen Mercedes 450 exhaust manifold bolts, steel bolts to aluminum head.

Main thing that worked I think was time. I built little dams of clay and aluminum foil and put in tubing to them so i could fill the areas frequently, keeping the bolts immersed continually in the fluid.

I think I kept it up for a month or more, just figured taking a lot of time would be worth it.

Mike

 

[ToadHill]

I like PB Blaster. It seems to work better for me than anything else I've ried.

 

[RichNJKubota]

Too bad you can't get Kroil. For me that's the best. Short of that you have some options. PbBlaster is good.
You can use heat - 2 ways. Heat the nut/stud up with a torch. Not too hot. Then soak it in rust penetrant. Repeat over and over till it loosens up. Or you heat the nut on the stud up till it's red hot. Then let it cool. It should just come off. Somehow the heat breaks the rust connection between the nut and stud.
Or you can us a Dremel tool with a steel cutting disk and cut the nuts off the studs.

 

[CurlyDave]

Kroil is the best I have ever used.

Heat and candle wax is touted by some on TBN as being very good.

When you get them off, put high temp anti-seize on the new ones before you reassemble.

Whenever I get a new car or truck I treat the manifold, the exhaust system, and the lug nuts with anti-seize. Saves many hours of "blessing the bolts" down the road.

Used vehicles, it isn't worth the trouble, the parts are already rusted together.

 

[cast_and_blast]

Deep Creep - I think I even saw it at WalMart.

Scott

 

[AlanB]

This is kind of like a Ford Chevy Debate.

In the FWIW I use the "penetrating Oils" as one of my examples when a new vendor walks through the door. They all seem to have one, and thiers is "the only one that works"

We carry about 8 different ones, and not a month goes by that someone does not want a different something because the one in the pink can is "the only one that works"

All that being said, Yeild is up there in my books with Kroil products.

I have some Zep 45 at the house playing with it and it works pretty well too.

I think time, heat, repeated applications and patience are the big ingredients.

I think each situation is a bit different, and folks get strong opinions formed when a product works right away, (especially after having tried something else) then on the next stuck part something else does not work.

Good luck. Let me know when you find "the only one that works"

 

[Kays Supply]

I took a Yanmar diesel head to a machine shop for a repair. They said it was unrepairable because they ruined the injector trying to press it out. I took it home and sprayed Pb Blaster on the injector every morning as I left for work. After several days one tap and it hit the floor. I have many more tails of the amazing PB. As said, time is a big factor.