Old Mechanic Trick To Removing Rusty Exhaust Manifold Bolts!

For those of you that have been following me for awhile I'm sure you might have seen this video before. I wanted to see if it generated any views again so I hope yall are patient

Here's an old Aircraft Mechanic's trick shared with me to loosen rusted in bolts. Go to a local pharmacy and you'll probably have to order it, but order Oil of Wintergreen. It comes in 2 sizes and it's a bit pricey. Put that on your rusted in bolts once or twice, let it sit for a while and try loosening the bolts. I bought some to change wheel lugvnuts on a boat trailer near a beach shore buried in a sand dune. I waited about 20 or 30 minutes and the nuts came off like butter. Oil of Wintergreen is acidic and eats away the rust and it smells awesome. I bought a 4oz jar I think it was and I still have some left after about 40yrs.

I'm a retired hydraulics mechanic. Taking apart seized hydraulic cylinders was my specialty. Never forget that the heat you apply to something will migrate. If you heat too close to the bolt at the beginning, by the time the heat is there it has migrated to the bolt so the bolt has expanded too. Also, the manifold acts like a heat sink so it takes longer to warm up. Therefore start applying the heat to the greater mass of the manifold further away from the bolt, thereby creating a heat-hedge. Then heat the area that is exposed, and easier to reach. Now you have more hope that the bolt did not expand together with the manifold. Enjoy!

When I removed exhaust manifolds on now vintage automobiles, I would always begin with a warmed engine. This provided much success.

Sometimes I find it helpful to hit the bolt head with a large drift and big hammer as well, to break the galvanic bond.

Stephen - small suggestion, I’m no professional mechanic but I was taught by a machinist not to use a threading tap for thread repair. Any damaged or misaligned threads will be cut away and removed, leaving a weaker thread behind. Thread chasers or thread repair taps work to realign and straighten any damaged threads. Lang makes the sets for the tool trucks but you can buy it directly from them for less. Lang 971 is the parts number.

Annnnnd here’s a man that’s snapped a lot of exhaust manifold bolts/studs and isn’t gonna do it again!! Excellent job my friend!! God bless~

Old mechanic guidance says tight fasteners are easier to break loose by tightening them first. You'll be amazed.

Your 100% right ! I was a mechanic on industrial machines, forklifts , skid loaders and so on , for over 50+ years I seen bolts and studs brake all over ! The best advice is what you show , slow and steady , use the right tool and penetrating fluid , the biggest problem is people use the bolts again! When doing cyl heads with studs we always use new hardware , try to get off a old flathead with studs ? LOL the young people have no patience but slow and steady is always better then half a day drilling out bolts or welding nuts to remove them , a mechanic’s nightmare LOL. Thank you your the best !

Tighten the bolts back down to keep the part from warping and putting added tension on the others… Genius

Very well explained, and very well videoed. One tip, instead of the ratchet wrench, use a breaker-wrench. Not so much fiddling around with the direction selector. Quicker and easier. Just wiggle it back and forth.

My dad was a Tool & Die Maker/Master Machinist ... and I helped and watched him fix anything and everything to do with nuts and bolts and everything... This was like watching and learning from him. He was always careful to loosen and tighten in a pattern- as soon as you tightened that first bolt back I was yep- he doesn't;t want the whole thing to torque and put uneven pressure on the rest he won't be able to defeat." Dad may have not attacked them in straight succession- but would skip around- putting back together very evenly. but your tightening back is exactly the same effect. Kudos - I have subscribed.

Finally, a mechanic video that knows how to set up a good closeup with good lighting. Excellent video sir.

Great advice. My advice to add: vibrate the bolt or nut with an air regulated air hammer After spray & soaking with penetrant. Use low pressure/light impacts to prevent any bolt or nut damage. The vibrations help the penetrant soak in better/ deeper and break up solid rust chunks! I experimented with several anti-seize lubes over several weeks on a lab test engine DPF that was removed & weighed several times per shift, while very hot, to measure soot accumulation. Anyways the bolts would seize & I switched to stainless 5/16" bolts & those long coupling nuts which spread the clamp loads over more threads. That helped but would still seize quicker than I wanted, even with Permatex silver anti-seize. I finally had long term success with Bostic brand NEVER-SEEZ High Temp Stainless formula. It's super-fine powder stays in place & although the carrier grease lubricant burns away, especially on turbo manifold/turbine inlet studs, the dry powder acts as a sponge, wicking the spray penetrants deeper into the threads & prevents solid chunk rust formation. Once I incorporated Bostic Never-Seez, spray penetrant, light vibration from air hammer, & Then slight loosen, then slight retighten like you demonstrated Stephen, I almost never broke another turbo manifold bolt or turbine inducer stud on the LHU 2.0L GM EcoTec test engines again. I probably removed/reinstalled or replaced a turbo almost 100 times for the several year duration of various tests & taught several junior technicians my tricks so they wouldn't waste time breaking bolts. I despised seeing an untrained & arrogant tech from another building come over to "help out" when we were understaffed. They'd wave away our advice with "it's not my first rodeo" smart-elick comment! Soon I would get a $300 cast stainless turbo manifold with 3 or 4 broken studs to fix in my "spare" time & a request to take one of my new spare manifolds (they eventually warped from extreme testing at nearly 950°C) 👹🤬! Hope this helps someone. Blessing Stephen! Paul from S. Central Tx..

During my clumsy mechanical experiences with old vehicles, seems there is always one bolt of a series that resists all techniques for removal. Many years ago I was unscrewing huge lug nuts on old truck rear wheel with left hand threads. One nut resisted until I broke the wrench (equipped with long pipe extension). Old neighbor guy had been watching and suggested trying turning nut the other way. Yes, one of the left hand wheel lugs had been replaced with right hand. After cleaning up the nut, small “R” was visible.

Good advice on not removing the bolts until they're all lose. Had I known that, that would have saved me weeks of screwing around and busting my knuckles on a Ford V-10. Cheers from Canada.

After putting the penetrating oil on the bolts, tap the system with a brass hammer. The vibration causes the oil to penetrate. Yes use a 6 point socket on crusty bolts, metal has flaked away over time from the heat. If it's a 9/16 head, you can use a 14mm socket for a better grip.

This is gold. I'm an old retired machinist and car guy. Stephen is spot on dealing with rusted exhaust manifold bolts or other rusted bolts.

Love PB Blaster and if I know it's a weekend project, I'll go ahead and spray whatever bolts on Friday and let it sit overnight and start wrenching on Saturday !

Thank you for teaching me something new! I've been wrenching on motors for almost half a century and never was taught to put the bolt back in and keep the manifold flat. Now that you explain it, it seems so obvious! Liked and subscribed! ("Long live the algorithm.")