Started a thread a while back about this. But didn't know what I was talking about.

https://landroverforums.com/forum/di...e-518-a-75529/

 

Damn. Well I guess ill bump RTV back to being used only on diffs and intake/exhaust. I'll have to try that Hylomar.

 

Personally, I've used black RTV on every project you can imagine for 20+ years and never had an issue. Instead, I've had problem free jobs where I never had to pull things back apart because it was still leaking. I've never had an engine fail, and in fact have replaced head gaskets and had the engine run for another 100k miles (for a total of >250k) and then be sold while still running fine. No, I didn't put black RTV on the head gaskets, but I put it on just about everything else!

And bear in mind RTV is the standard sealant used by zillions of mechanics around the world everyday. I have think that if it was really such bad stuff there would be a much higher rate of catastrophic engine failure.

I seriously doubt I'm gonna stop using it now, though I might look into hylomar after I finish this tube of black RTV. Maybe.

 

I'm pretty careful with it. I don't use a bead, I smear a thin coat. I let it dry some before I but things together. I run my finger along the inside to keep it out of the engine. But some always presses outside of the mating surfaces and, over time, it will break off.

I used to use black rtv and have used it on waterproofing four wheelers. All of the black I have ever used dried hard. The other colors stay somewhat soft. I've tried different brands.

But I'm not trying to tell anyone what to do. I've just been in the unique and unenviable position of staring into my pickup tube and timing cover three times in one week and after the first time I was super, super careful with the rtv. There was rtv in it each time, and not just the rtv (by color) that I'd used the last time. The only places I have ever used rtv are on the oil pan, the timing cover, the rubber that holds the valley gasket down, and the water pump. I use different colors each place so I know where it came from. The red is coming from the valley gasket rubber and I haven't added rtv there in months. Also, I have had the valley gasket off (to check lifters and rods, and replace heads) and made sure that there was no extra red, yet I keep finding little specks after several oil changes. I guess it is just flaking off.

Anyway, I'm not telling what I presume to be grown men what to do. I just noticed that there alot of threads, including my own, where the OP did something unrelated to oil pressure (like swapping the heads), put it back together, and suddenly had low oil pressure, and am suggesting a possible cause. When I opened mine up to investigate I found a bunch of it in the pickup tube. I also found "hairs" which I have traced to the shop towels I was using. I am a clean freak on the inside of the engine and I was wiping things down and leaving lint that I couldn't see. That ends up in the pickup tube, too. Thanks, Sams Club.

My rover has leaked since I drove it off the lot in 1999. I was so pleased with myself when, with the miracle of rtv, I could park on fresh concrete without leaving a mark. But I'll just leak. The leaks keep it from rusting anyway. Hylomar sticks to itself, if it wasn't so expensive I'd smear it everywhere.

I'm not a new dog (Number9), I'm an old dog. But when I need to know the precise answer to something you are definitely the man I want to ask.

 

Hylomar Blue supposed equivalent is available also. Would recommend using acid brushes for applying to gaskets. Contact cleaner works well for clean up of hands and tools. Purchased from vendor when ordering brass coolant bleeder tee screw for $5.00.

Hylomar Blue equivalent:
VICTOR REINZ Sealing Compound - Victor Reinz REINZOPLAST Blue (80 ml. Tube) 559526007

Bleeder screw:
Mini DOMESTIC AFTERMARKET Bleeder Screw with O-Ring for Cooling System 17111712788

From a sealant mfg:......

 

I have used Red RTV for years on my BMW's which are far more precision engines and have never ever had an issue with them. If you know how to apply the stuff and PROPERLY torque your parts it shouldn't be an issue. ANY sealant that is put on in globs and over-torque so that it is promptly squeezed out and pinched off by working parts has the potential to gum up your engine.

 

I used RTV for years which appeared OK and sealed well until one day I had to take the rocker cover apart, frickin stuck, it wouldn't budge even with the bolts removed, it stuck like the proverbial to a blanket. So I used Hylomar, now I'll use nothing else, it seals well but the big difference it comes apart easily. RTV is great provided you anticipate you'll never need to remove the equipment again and when you finally take it apart the RTV takes an eternity to clean off.

 

We aren't using black rtv. Mechanics are using ultra black, or the right stuff. Usually good tubes of sealant, maker are more expensive than the typical.
Certain ingredients make sealants better than others.