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.

 

[elad]

PB Blaster, saved my you know what,
more than once.
Wouldn't be without it.
elad

 

[Scooby074]

Thanks for the opinions guys! Yes its definately a Ford / Chevy or Deere / Kubota debate.

Thats why i was hoping for someone to know a scientific, unbiased study. Ive read the study by Home Shop Machinist JJ mentioned. Its the famous ATF/Acetone test published all over the net. Considering hot hotly this topic gets debated I was hoping to find some confirmation of those results somewheres.

All and all it was a frustrating day. I went to Zep to get a couple cans of their penetrating fluid and a gallon of hand cleaner, only to find that their new policy requires an order of at least $150 Im not a Business major but it doesnt make sense to pass up a $60 sale. The salesman told me it has cost them most of their counter sales and some of their small commercial customers Oh well.

So I ended up at the GM dealer and bought some of their Penetrant based on Sackett2's recomendation. Soaked the manifolds tonight, found a couple broken studs. I have to finish springs on a Toyota then the Ford goes into the shop tomorrow. Cant wait to get started...Not.

Dealer estimate was at least $700 for this job. After looking at it i can see why! No idea what im gonna charge. It will depend alot on how Pi33ed off i get

Ill post my opinions on the GM stuff when Im done. Maybe I found a replacement to my usual goto Kroil.

 

[Matt_Jr]

I agree with the small amount of heat, oil, and time. Heating not only causes the nut to expand but also causes the gases trapped in the rust to expand and push out. Directly after heating drench the area with penatrating oil to cool materials. This cooling will cause a vacuume in between the threads and penetrating oil will be drawn into the threads. Repeating these steps also helps tremendously. After following these steps several times, use an air chisel or a long chisel and hammer to turn the nut by hitting it on the edge at an angle that will force it to turn. I worked at an exhaust shop for a while in my automotive career and learned a lot of tricks from some experienced old timers, and this is one of the best and most successful ones I've learned for freeing rusted nuts. Penetrating oil brand is less important than technique. Good luck.

 

[Wheatland KB]

I know that I have had luck with brake fluid. Anyone else or was it just luck?

 

[Scooby074]

, use an air chisel or a long chisel and hammer to turn the nut by hitting it on the edge at an angle that will force it to turn. I worked at an exhaust shop for a while in my automotive career and learned a lot of tricks from some experienced old timers, and this is one of the best and most successful ones I've learned for freeing rusted nut

Interesting points. Yeah i had planned on taking the torch to it first. Id like to think i could get in there with the chisel, but looking at it i dont think i got the room. The f150 is pretty tight. Definitely not designed by a mechanic. I think im going to have to take the inner fenders out anyways to make room to work. Im gonna need all the luck i can get

 

[JDeerekid]

Dealer estimate was at least $700 for this job. After looking at it i can see why! No idea what im gonna charge. It will depend alot on how Pi33ed off i get

That is how I usually charge for work

 

[DieselPower]

There have been many good penetrating sprays suggested here but for rusty items like exhaust system components I think you will find there are few things that work as well as a propane torch and and paraffin canning wax. Heat the bolts or nuts with the torch and press the bar of wax against it. The rust acts as a wick sucking up the melting wax. A old now retired mechanic taught that to me years ago at a dealership I worked at. Works great on rusted bolts stuck in highly oxidized aluminum parts like water necks and water pumps.

 

[bdeboer]

I have had good luck with Fluid Film, the Deere dealers around here carry it.

 

[dirtworksequip]

I've seen Zep 45 break loose nut,bolts and studs on heavy equipment that I thought were impossible to get loose. Maybe try a little heat and spray on the Zep so it will work its way down into the threaded hole.

Sincerely, Dirt

 

[gemini5362]

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.

In the for what it is worth factor I also like PB blaster it has worked well for me.