Headlight seal recommendations

[StuntmanMike]

I am going to strip a headlight down this week.

What is the best sealer to apply on rebuild?

Silicone?

Butyl tape?

Anything else?

Thanks in advance.

[Subterra]

If it's any help, quite a few years ago I found some clear sealer like tiger seal.
I had opened up some large HGV headights to clean them out owing to water ingress.
Cleaned of all the old sealant from rear plastic mouldings and the flat glass fronts, that was a mission.

Applying the new seal was also a task that involved great care as this stuff stick like chit to a blanket.
The tube was dispensed from a skelie mastic gun.
Does not keep however once the metal seal is broken, set rock hard.
May have ordered from Amazon, I know you can get white & grey.

[StuntmanMike]

Ta, if it works on HGV headlights etc.

This was going to be my approach but I keep seeing advertisements for Butyl tape.

In your opinion can you split this headlights again? Or is this a if it doesn’t work chuck them away thing?

Also, out of interest, what has the truck?

[LightweightLouisDanvers]

Might have to give this a go, one of the headlights on my son's Polo seems to be suffering from water ingress.

[21TonyK]

LightweightLouisDanvers said:

Might have to give this a go, one of the headlights on my son's Polo seems to be suffering from water ingress.

As are my daughter’s rear lights on her polo. VW want 150 diagnosis fee to see if it’s covered by warranty!

[Belle427]

Tiger seal is great stuff but if you ever think you are going to need to get stuff apart again then use something else!

[Smint]

I read somewhere of a suggestion for aquarium glue, haven't used it myself but its obviously meant to see some damp conditions.

[21TonyK]

I've got half a tube of RTV to use up. Will do the job long enough.

[E-bmw]

RTV silicon is cr@p in these circumstances, I would rather use pretty much anything else personally.

[21TonyK]

E-bmw said:

RTV silicon is cr@p in these circumstances, I would rather use pretty much anything else personally.

Noted. It's on the job list for monday so I'll pick up some proper silicon over the weekend. Its only a weep on a rear light and she'll be changing the car by the end of the year.

[E-bmw]

21TonyK said:

E-bmw said:

RTV silicon is cr@p in these circumstances, I would rather use pretty much anything else personally.

Noted. It's on the job list for monday so I'll pick up some proper silicon over the weekend. Its only a weep on a rear light and she'll be changing the car by the end of the year.

You misunderstand me RTV silicone is the only type you can realistically buy & is cr@p for use externally.

The best stuff to use is Tiger Seal or similar.

Exterior "no-nails" is better than silicone.

Contact adhesive is better than silicone.

[LightweightLouisDanvers]

Whats the best way to take headlights apart, heat around the seams with hairdryer/ heat gun, bake at gas mk3 for 30 mins?

[E-bmw]

It depends on how the headlight unit was constructed.

E39's (last ones I did) were a gently warm with a hair drier.

Some are actually melted together.

You will need to see how yours are put together and how they are sealed.

[Dogwatch]

I have had to deal with a leaking Focus headlight and a completely separated glass headlight lens on the runabout/tip car (circa 2000). Fixing both with decent quality clear sealant (e.g., Bostik OB1) has worked so far. Obviously the separated lens was easiest to deal with as it was mainly cleaning off the remains of the factory glue, using glasses wipes on the lens interior, reflector and bulb and reassembling. Both units used halogen bulbs.

The leaking headlight was more of a challenge as it persisted despite removing as much electrical stuff as possible and swilling the lens interior with deionised water to a) clean street grime carried in by the leak b) locate the leak. The leak's location was elusive until I realised that while the water flows into the unit freely due to wind pressure, it takes its time to start dripping out under gravity. Once dried out and sealed the unit has been fine since.

[21TonyK]

E-bmw said:

21TonyK said:

E-bmw said:

RTV silicon is cr@p in these circumstances, I would rather use pretty much anything else personally.

Noted. It's on the job list for monday so I'll pick up some proper silicon over the weekend. Its only a weep on a rear light and she'll be changing the car by the end of the year.

You misunderstand me RTV silicone is the only type you can realistically buy & is cr@p for use externally.

The best stuff to use is Tiger Seal or similar.

Exterior "no-nails" is better than silicone.

Contact adhesive is better than silicone.

Looks like its going to be a dab of CT-1 (also good at repairing captive nuts on air filter boxes)

[E-bmw]

21TonyK said:

E-bmw said:

21TonyK said:

E-bmw said:

RTV silicon is cr@p in these circumstances, I would rather use pretty much anything else personally.

Noted. It's on the job list for monday so I'll pick up some proper silicon over the weekend. Its only a weep on a rear light and she'll be changing the car by the end of the year.

You misunderstand me RTV silicone is the only type you can realistically buy & is cr@p for use externally.

The best stuff to use is Tiger Seal or similar.

Exterior "no-nails" is better than silicone.

Contact adhesive is better than silicone.

Looks like its going to be a dab of CT-1 (also good at repairing captive nuts on air filter boxes)

CT1 will do it just fine, it actually sticks to the plastic (make sure it is clean) and remains flexible to boot.

[p4cks]

Tiger Seal

[E-bmw]

p4cks said:

Tiger Seal

CT1 is pretty much the same thing.