Seized bolt removal

[DamoC43]

Hi all,

A problem most of us have or will likely encounter at some stage of our lives is a rusted / seized bolt. Mine is in a turbo housing on the exhaust side (Hot side) and i can't get a socket onto it due to the compressor flange being in the way. I can however get at them with a ring spanner.

Anyway the main question concerns using heat - should i try and focus the flame on the bolt or the material it's bolted into - or both? Have come across some conflicting advice online (surprise...) so wanted to see if anyone with first hand experience could share some wisdom? It's the first time I've ever resorted to using heat. (Got myself a torch and will buy some MAPP gas as i believe it's hotter than Butane / Propane.

Failing success with this approach i'm left with a cutting wheel solution which i'd like to avoid if possible

Many thanks

 

[Texas]

I've learned that SOMETIMES you can gently tap the flats on the bolt head while it's room temperature and the bolt will come out. Back and forth movement helps if it gets tight loosening. Next would be the heat. Focus it on the bolt ONLY. Get it red hot, then walk away. The heat stretches the bolt and breaks loose any rust, ect that's keeping it from turning. Let it cool to touch and see if it will back out. More often than not, it will. Upon reassembly, use top grade antiseize.
Please ensure you replace all the bolts with new. Its CHEAP insurance against a broken bolt later.
Michael

 

[Petrol Pete]

In my experience using a 'big' gas flame is less effective than using a 'pencil' type flame that you can be very accurate with . By 'big' I mean the MAPP gas type flame that a plumber might use soldering a copper pipe , in that case you want the heat to spread fairly evenly to melt the solder.

This is a better option for accurate surface heating.

Find the best price on PriceCompare24.com

Find UK's best products, always on the best price and fastest delivery!

www.google.co.uk

 

[Chrishazle]

For a small hot flame, how about a chef's blowtorch using normal gas lighter gas? Much cheaper than the MAPP thing!

https://www.amazon.co.uk/KitchenCraft-KCBLOWTORCHCP-Cooks-Blowtorch/dp/B016OVKFKI/ref=sr_1_3?dib=eyJ2IjoiMSJ9.f8oC5KgZw7YakktMdnKFZMHljFrVKRPJcpgsV6lMbuEdnQQlVwhxVo8ITqZUt-L-SXHLByq6LYFd4TDDzUeTEPIsYC8n2jpx_uIlGogW7sug3yvhOmWRJCE3PCcq1PauOPOW0TfhlvuKYelb1Y-z-ndjckF6SVrwDE_-7wSG21XkXL2Jrg9KcIMHBfqIsoan5kGRLModuxMQUGgvHeE4LbdAp5YzplSCQkeKfeZF6_8.Vqx7YtFg1YwTs0PzQQsJMGnMTzI0_1kjxd9tgDnsVLM&dib_tag=se&keywords=KitchenCraft+CooksBlowtorch&qid=1725975533&sr=8-3

 

[Petrol Pete]

For a small hot flame, how about a chef's blowtorch using normal gas lighter gas? Much cheaper than the MAPP thing!

https://www.amazon.co.uk/KitchenCraft-KCBLOWTORCHCP-Cooks-Blowtorch/dp/B016OVKFKI/ref=sr_1_3?dib=eyJ2IjoiMSJ9.f8oC5KgZw7YakktMdnKFZMHljFrVKRPJcpgsV6lMbuEdnQQlVwhxVo8ITqZUt-L-SXHLByq6LYFd4TDDzUeTEPIsYC8n2jpx_uIlGogW7sug3yvhOmWRJCE3PCcq1PauOPOW0TfhlvuKYelb1Y-z-ndjckF6SVrwDE_-7wSG21XkXL2Jrg9KcIMHBfqIsoan5kGRLModuxMQUGgvHeE4LbdAp5YzplSCQkeKfeZF6_8.Vqx7YtFg1YwTs0PzQQsJMGnMTzI0_1kjxd9tgDnsVLM&dib_tag=se&keywords=KitchenCraft+CooksBlowtorch&qid=1725975533&sr=8-3

Usually Not hot (fierce) enough , but worth a try . I have both (hot air gun as well) and a tiny pocket torch that I fill with lighter fluid . All worth a try . Heat is normally your fiend in these applications.

 

[DamoC43]

In my experience using a 'big' gas flame is less effective than using a 'pencil' type flame that you can be very accurate with . By 'big' I mean the MAPP gas type flame that a plumber might use soldering a copper pipe , in that case you want the heat to spread fairly evenly to melt the solder.

This is a better option for accurate surface heating.

Find the best price on PriceCompare24.com

Find UK's best products, always on the best price and fastest delivery!

www.google.co.uk

Awesome, thats pretty much the same as i've bought. I do have a plumbers torch already but as you say the flame is too big and when you tilt the can it goes from a nice controlled blue flame to and out of control yellow one!

 

[DamoC43]

I've learned that SOMETIMES you can gently tap the flats on the bolt head while it's room temperature and the bolt will come out. Back and forth movement helps if it gets tight loosening. Next would be the heat. Focus it on the bolt ONLY. Get it red hot, then walk away. The heat stretches the bolt and breaks loose any rust, ect that's keeping it from turning. Let it cool to touch and see if it will back out. More often than not, it will. Upon reassembly, use top grade antiseize.
Please ensure you replace all the bolts with new. Its CHEAP insurance against a broken bolt later.
Michael

Thanks, I'd not known about leaving it to cool right back down so i'll certainly try that. Might also save me some burnt fingers in the process - good shout

 

[DamoC43]

Usually Not hot (fierce) enough , but worth a try . I have both (hot air gun as well) and a tiny pocket torch that I fill with lighter fluid . All worth a try . Heat is normally your fiend in these applications.

Yes i'd read that while the little mini torches are good for getting in tight spaces they're usually not hot enough (Aparently) so i've bought a smallish hand held torch with hose. The MAP canisters from tool station are only £13

 

[BlackC55]

You heat the housing of the bolt always. Use a thin, direct flame and heat to cherry red.

 

[Trickythemerc]

Good soaking in Plus Gas

 

[DamoC43]

Ok so far i've given them a good soak in WD, topped up 3 or 4 times over last 24 hours. I've just tried heating the bolts, well bolt heads and am waiting for them to cool down. As if this weren't already hard enough the AF size of the bolt heads is weird. I measured one with a micrometer and got 9.6mm. I already knwew 10mm felt too sloppy so i went out and bought an imperial set of spanners for a 3/8ths. Perhaps they began life as 10mm and have corroded in size? The 3/8 fit on better but are still not great + they're 12 pont not 6 which would have been ideal.
If this doesn't work i'm going to take @BlackC55 advice and try heating the casting instead. Would shock cooling it after heating help or am i asking for trouble?

 

[Bellow]

Can the engine still be run up to temperature? If so, and the bolt be accessed immediately, you'll have deep soaked heat exactly where needed.

 

[DamoC43]

Can the engine still be run up to temperature? If so, and the bolt be accessed immediately, you'll have deep soaked heat exactly where needed.

Affraid not, the whole turbo has been removed already. They'd have been a nightmare to access if still fitted. Good idea though, would probably work on other designs

 

[DaveE320CDI]

You heat the housing of the bolt always. Use a thin, direct flame and heat to cherry red.

Agreed its the housing that you want to expand to free the bolt NOT the other way round! if you heat the bolt it will expand and only make the interference between the threads tighter, Blackc55 is the way to go

 

[DamoC43]

Ok update: I tried the first bolt before any other suggestions and it broke free, The next one snapped, of course halfway down the hole, and the remaining 2 were too rounded to get any sort of meaningful purchase on them - so in frustration they have been sacrificed to the cutting wheel of death. My angle grinder shall dance around them naked at midnight.

Thanks for all the advice and suggestions though everyone - much appreciated. Are these special bolts or could i replace with standard stainless (That have a normal sized AF dimension)?

Cheers

 

[Texas]

My experience says always go with oem. LH drill bits help remove broken bolts Sometimes.

 

[Bellow]

the remaining 2 were too rounded to get any sort of meaningful purchase on them - so in frustration they have been sacrificed to the cutting wheel of death. My angle grinder shall dance around them naked at midnight.

If they've not succumbed to the cutting wheel yet - a well aimed cold cut chisel might be enough to get them loose.

 

[johnsco]

Ok so far i've given them a good soak in WD, topped up 3 or 4 times over last 24 hours ........

WD40 was not designed as a penetrating oil ... and it is far from the best for this sort of job.
Plus Gas is much better.
WD40 was designed as a water-dispersant and is great for that.

 

[ALFAitalia]

But it does the job.....From WD-40 website.

Myth: WD-40 Multi-Use Product is not really a lubricant.

Fact: While the “W-D” in WD-40 stands for Water Displacement, WD-40 Multi-Use Product is a unique, special blend of lubricants. The product’s formulation also contains anti-corrosion agents and ingredients for penetration, water displacement and soil removal.

 

[Petrol Pete]

Yes i'd read that while the little mini torches are good for getting in tight spaces they're usually not hot enough (Aparently) so i've bought a smallish hand held torch with hose. The MAP canisters from tool station are only £13

Wrong , the right mini torch with the right gas gats plenty hot enough to melt stuff that you really did not want to melt , more than enough to get stuff cherry red.