RTV Gasket Sealer on Intake Manifold Gaskets?

[Echo30V]

All

I've been chasing down some minor oil leaks on my 1990 325i Vert. I just replaced the Oil Pan gasket which cut the oil leaks in half. So I traced the final leak (I hope) to the Oil breather tube. Accordingly I will be pulling the intake manifold to access the breather tube.

I've read many posts on the subject but am a bit confused whether or not to use a gasket sealer when replacing the intake manifold gaskets. Some people use a sealer and some indicate no sealer needed and to just make sure both surfaces are clear of any old gasket. So when I replace the old gaskets should I use a gasket sealer to mate the gaskets to the intake manifold or not?

[zaq123]

invest into a tube of Curil K2, great sealant. here is a data sheet

https://www.elring.de/fileadmin/Dateiablage_DE/2Service/Datenblaetter/Technische_Dichtmassen/Cruil_K2/TD_Curil_K2_EN_01.pdf

[Echo30V]

Thanks, so is a sealer necessary when replacing the intake manifold gaskets or just bolt up dry?

[jeffnhiscars]

Im also a fan of Kuril but NOT for the intake manifold. Install it clean and dry

[zaq123]

why do you want to use sealant in the first place? Did you scratch your intake surface/head ports when removing old gaskets? If you have some minor imperfections, Curil is good stuff and makes future reassembly easy. If you there are no issues and just worried.......no sealant needed. OEM gasket will do well

[Echo30V]

No, I did not scratch anything and never indicated that I wanted to use a sealer. I read a number of threads and articles about replacing intake manifold gaskets. Some people used sealer and some did not. I was leaning towards not using sealer but wanted to make sure.

[TobyB]

I don't use sealer on anything but the water neck and half moons,
and that's just leftover habit from the 2002...

Permatex gasket sealer on 'paper', Ultra Black on 'rubber'...

whut I do
t

[Kershaw]

Use as much sealant as possible on the damn crank case tube. Damn thing never seals.

[MrBurgundy]

I've never used a sealer on an intake manifold gasket and I've never had any problems.

Clean and dry is my 2 cents.

[digger]

i use non hardening aviation cement (brush on stuff) no silicone or rubbery shit. it fills in the fine machine marks on metal surfaces, yet it wipes off easy with carby cleaner on a rag later on. use it sparingly so it doesn't squeeze into the runner

[e30davie]

Use as much sealant as possible on the damn crank case tube. Damn thing never seals.

why do people have so much trouble with that tube?

I cleaned it, put new o-rings in, seals good, happy days?

[jeffnhiscars]

why do people have so much trouble with that tube?

I cleaned it, put new o-rings in, seals good, happy days?

Because they don't zip tie the spring, put the intake on, then cut the zip ties.

[e30davie]

yeah that's what i did, i couldn't see any other way of doing it, was easy as to put in with that method...

As for original question, i avoid sealant on as much things as possible on. Unless the surfaces are damaged beyond repair the prescribed gasket should seal properly. If it doesnt specify sealant in the Bentley manual, it doesn't need sealant.

A flat file across the surface of the intake manifold cleans it up nicely and can reveal any potential issues.

[15Michaeljoseph]

I've done the intake manifold gaskets thee times on my car (once when I first got the car, and twice as part of head gasket nonsense), and never used sealant. No issues. Just remember to tighten the intake manifold nuts from the middle to the sides equally on both ends.

Also, make sure you get two new o-rings for the bitch tube, I like to put a dab of motor oil on them when I install, makes me feel like they'll slip into place easier. No sealant needed here either.

Places to use sealant on an M20: rocker shaft plugs, coolant flange on the back of the head, water pump gasket, oil pan "edges", header to downpipe connection (acoustiflex sealant or comparable), brake booster hose elbows to throttle body holes...... That's pretty much it as far as my experience has held.

Sent from my XT1064 using Tapatalk

[Echo30V]

Thanks all. So yesterday I changed out the transmission fluid, replaced motor mounts and tranny mounts. Went with BMW rubber.

Waiting on parts for the Bitch tube fix. I'm not going to use any sealant when I replace the intake manifold gaskets. I am getting a oil leak from the breather tube area so I decided just to order a new tube and seals. I will utilize the zip tie method when I replace.

Next up is going to be a differential swap. I have a 1990 325i vert with a build date of 9/89. I checked the vin and this whip came with an 3.73 LSD as an option. However, the more I drove it, the more I thought something was amiss. I checked for the tag on the differential but no tag present. I used a mirror to see if the top of the differential was stamped. No stamp. Did wheel spin test and the wheels rotated in opposite direction.

The case is stamped 1210411. Does the 411 mean its a 4.11 open? Anyway, sourced a 3.73 LSD. I was thinking of doing a refresh on the LSD differential. Thinking all new rubber seals and new friction plates and maybe new dog ears. Don't think I'm going to mess around with the pinion area.