Technical Bolts, nuts pain in the

[koalar]

These cars are over 10 years old, on UK wet and salted roads it's inevitable you will come across seized fasteners

There isn't one size fits all

Take heat to a nylock nut and you may make the situation worse

However heat and or impact are the most effective

Penatrating oil normally only does anything, once you have already freed the the part slighty or you have access to the back of the fastener

No amout of time soaking will allow the oil to pass through a gap that does not yet exist.

Here I have a salt celler and the top and bottom have seized together

It's only plated, so I can not try too much heat, I have tried a heat gun while the bottom half was wrapped in a wet cloth and that didn’t work, I was going to go over to impact

However as an experiment I will soak in Wd40 for a couple of hours, clean it off with meths and then dismantle even if I end up smashing it apart and see how far if any it's penertrated

Unfortunately I have already clean it a bit to see if it was worth salvaging, but originally there was a green corrosion line around the middle

Here is a brake pipe a did awhile back

Left to soak over night in penetrating oil, worth a shot, nothing to loose

Still needed heating to cherry red

The oil on the threads is from working the union backward and forwards after it was loose

 

[koalar]

Leverage is king

Well to a point

There's a lot of variables here as well

A 10 mm socket fits a M6 bolt which has a minor diameter of 5 mm. The top wrench would easy snap it especially if it's corroded reducing it's minor diameter even more

It takes experience to know where the limit is,

 

[jrkitching]

Just occasionally, you get a nice surprise.

I changed the rear shocks on the Panda a couple of weeks ago. I wasn't looking forward to doing this, as I expected a fight with the bolts - they'd been in there 13yrs. The threaded section is well embedded; so not a great deal of point trying to use any kind of releasing fluid; you'd never get it to where it matters. And the external appearance of the bolt heads didn't give me much hope.

In truth, I'd been putting this off; I finally went out about 4pm (with an MOT next day), armed with breaker bar, an impact driver and a swear box. To my complete astonishment, they just came straight out with a socket and 12" ratchet handle; the first shock was on the bench in less than five minutes.

These are the bolts; not bad at all after 13 years in place.

 

[jrkitching]

If you aren't going to reuse the fastening, it might be quicker to cut it off; much depends on how much access you've got.

You can use anything from a hacksaw to a dremel to an angle grinder, but a small battery powered cutoff tool like this one is a good compromise. Something similar turns up in the middle aisle at Lidl from time to time.

Works particularly well for removing droplinks; another job well known for immovable fastenings.

Just be careful about where the sparks are going; protect anything made of rubber that you want to keep, like the driveshaft gaiters.

 

[chris3234]

Just occasionally, you get a nice surprise.

I changed the rear shocks on the Panda a couple of weeks ago. I wasn't looking forward to doing this, as I expected a fight with the bolts - they'd been in there 13yrs. The threaded section is well embedded; so not a great deal of point trying to use any kind of releasing fluid; you'd never get it to where it matters. And the external appearance of the bolt heads didn't give me much hope.

In truth, I'd been putting this off; I finally went out about 4pm (with an MOT next day), armed with breaker bar, an impact driver and a swear box. To my complete astonishment, they just came straight out with a socket and 12" ratchet handle; the first shock was on the bench in less than five minutes.

These are the bolts; not bad at all after 13 years in place.

The top bolts are inside a box section I think so thankful well protected

The lower ones are definitely a little exposed. It have done well,

 

[jrkitching]

The top bolts are inside a box section I think so thankful well protected

The lower ones are definitely a little exposed. It have done well,

Yep, the top ones (the smaller bolt) were indeed like new, apart from the head - and once loosened, came out by hand.

 

[koalar]

A problem that goes hand in hand with seize bolts

Is the heads rounding off

A good example of this is the bolts that hold the exhaust heat shield on

The heads will nearly always be corroded well below the original size also with the threads seized

Theres no space to cut them off without removing the grill and radiator

Socket should be a 10mm but an imperial 3/8, (9.5 mm) is often a better choice, especially if it needs to be tapped on

Quality of the socket also makes a difference, there are many great designs but whatever you use it needs to fit well

Some brands are 0.1mm over nominal and others 0.2mm oversized which is very sloppy and asking for trouble especially on the smaller sizes

These bolts are also a good example of where a penitrating oil works a bit. The back of the bolts are visable, as you unscrew the bolt it gets drawn into the threads.

 

[koalar]

Right got it apart

i placed the bottom in a vice lined in soft woodh then wrapped the top in leather and clamp it with mole grip, some sharp taps to the side of the mole grip with a hammer after about 10 hits I felt that horrible scratchy feeling, But the mole grips hadn't slipped it was salty grit in the threads

Anyhow there isn't any sign of oil on the threads

That a couple of squirts a few hours apart, and then left over night

The results are as I expected

If the parts have grown together and/or the matting surfaces are flush how can the oil get in

I could have filled the container with oil and submerged it in oil, but sqirting a couple of times is more realistic to what we do on a car