waxoyl underbody seal

[johnf]

I have rust on the engine support mounts in my sail boat. This was treated with rust inhibitor and painted about 2 years ago but is getting rusty again. Access is very difficult.
I had wondered about underbody seal, but I see some people say this just seals in the moisture. I cannot really understand why this is so different from painting which again is a sealing process.

Would it be better to use rust inhibitor, then paint and then use Waxoyl underbody seal??

Thank you in advance

 

[PCUK]

I used it on rusty engine mounts and worked perfectly. No further problems.

 

[Malish]

just wire brush off the loose stuff and apply waxoyl to the metal.

 

[vyv_cox]

I use Waxoyl for exactly the same purpose, and for other locations such as tops of swaged rigging terminals.

 

[pvb]

Wasn't the OP asking about Waxoyl Underbody Seal, which is thick black stuff?

 

[Malish]

Wasn't the OP asking about Waxoyl Underbody Seal, which is thick black stuff?

well spotted, I would recommend the standard waxoyl be used

 

[PCUK]

I prefer the black as it looks better!

 

[vyv_cox]

I was not aware of Waxoyl underbody seal but Googling suggests it is actually Hammerite underbody seal with added Waxoyl. I was referring to Waxoyl, of which I always carry an aerosol can for small ferrous parts such as engine bearers.

 

[Scubadoo]

I use just waxoyl like others on here and works really well. I would not use the underseal type as that can flake off (or lift slightly) when very dry and then you get moisture and rust. I know this well as I have used underseal on my old landrover chassis and can be a problem after a few years.

 

[JumbleDuck]

I'm generally not a fan of waxoyl for steel sections, as I think it tends to skin over and solidify without penetrating. For that purpose I prefer Dinitrol 3125 which stays thin and seems to get everywhere.

I'm about to seal the Herald underbody and for that I shall use Dinitrol 4941, which is their equivalent of underseal, but still just a wax.

 

[matthewriches]

Dinitrol 4941 as suggested is very good. I've used it extensively on Land Rovers to good effect so sure it'd be good on engine supports.

 

[wombat88]

Look up Fluid Film which reaches the parts others cannot reach and never seems to dry. Lanolin based I believe.

Even stops old Citroens from getting any worse.