O-Ringing an inlet manifold gasket.

[30psi 4agte]

it is an option but do you think i will get away with just cutting a groove in the manifold flange or will i need to cut a reciever groove in the head ???

I know the reciever groove is the best possible way but im not about to pull the head off just to cut a groove

That PTFE stuff looks good. Do you think it would have enough crush to form a good seal ??? ----- Remember we are talking serious manifold pressure here !
Pitty have to buy a whole sheet when i only need a small piece !!

What do you think about using urethane and making a gasket from that say 1.5mm thick and about 70A hard ??

Im a litle concerned with the space i have in the o-ring causing a leak in that spot. I wanted to put the join of the wire on the side of the port between say runners 1 and 2 but having the join on the radius was tooooooooo hard to get the wire to sit there !!!

That way if there was a leak it would only leak between the ports . ---- no real big issue there.
Im concerned that that small gap may cause the same slight leak started with.
Im sure it would pose no prob on 95% of the engines out there but i bet my last dollar that if it will fail on anyone it will be me !!

[oldcorollas]

i think just one groove is fine.. the groove is designed to be a certain depth adn width, to provide sealign pressure and to restrict sideways movement

not sure on o-ring hardnesss specs.
i would choose one based on temperature and chemical resistance first (there are at least 3 or 4 different ones.. wasn't there links in a previous o-ring thread?)

yah, the join in wire might leak a bit... you will get that i suppose

small leak between wire is less bad than loosing whole gasket?
what about hylomar on the steel gaskets?

face type
http://www.epm.com/oring_grooves.htm

http://www.allorings.com/oring_groove_design.htm
http://www.allorings.com/gland_static_axial.htm

http://www.engineersedge.com/general...tic_flange.htm

http://www.usseal.com/orings/Glanddi...l_oring_6.html

etc... heaps of sites to design for O-ring flange seals.. they are very common in industry

these look cool!! teflon coating on Viton o-rings
http://www.m-cor.com/html/teflon_enc...d_o-rings.html

know where to download free SAE standards?
http://www.sae.org/technical/standards/MAP3439
edit: for serious (one off) sealing, you can even get soft metal o-rings, particularly used for unltra high vacuum systems

[30psi 4agte]

well looking at them i assume they are called the face type seal which is used with no reciever groove and uses the face to seal on ---- hence the name

Ill have a word with my mate and we will see just how much effort it is going to be to cut this groove. like you say though not sure how much room i will have to cut the groove into the flange. ---- Im at work at the moment so cant check but i do hav a pic on my lappy here somewhere will post it in a sec.

[30psi 4agte]

hmmmmm looking at this it may be a prob. the biggest concern looking at that is the outer parts of cyls 1 and 4 --- there isnt much meat there.

[30psi 4agte]

my mates have a cylinder recon / engineering buisness ( handy mates to have hence the access to the machine equipment) Anyhow when they pressure test heads the have various plates made up for different heads and the use a rubber gasket about 2.5mm thick to seal up ports and coolant passages etc etc. They then connect an air line with 100 psi to the head and dip the head in a tank to check for the bubbles that would come out if a crack was present.

What im getting at here is that i know a rubber gasket will hold 100 psi no prob the only down side i can see to using it as a gasket is that it will prob press out into the port once tensioned causing a flow restriction. This is why i was thinking along the lines of urethane as it will still alow good compression / crush but wont deform as bad.

[oldcorollas]

yeah, thats probabyl a no go even a 2mm groove takes up a lot of space there...
i wonder if there is more real estate for a small port?

hylomar and single metal gasket?
bitch to get off tho?

[30psi 4agte]

Yeah thats what i was thinking not enough room !! -- hence the gasket creation method being the no 1 choice now

Hylomar , copper coat ,wurth gasket goo, silicon (which i hate): ----Done it mate !! still not a perfect seal. You can see my delemar here

the best seal i achieved so far has been using permatext.

[oldcorollas]

What im getting at here is that i know a rubber gasket will hold 100 psi no prob the only down side i can see to using it as a gasket is that it will prob press out into the port once tensioned causing a flow restriction. This is why i was thinking along the lines of urethane as it will still alow good compression / crush but wont deform as bad.

oh i would never use an o-ring without metal on both sides... it will squeeze out and suck in if not restrained...
we use plain o-rings to get vacuums lower than 10^-7 torr? so they should be able to hold boost but def need metal on both sides.
you could use similar setup to a head, but you will probabyl not get the sealing force needed (from torqing bolts...)

hmm.. grey loctite fuel resistant 2 pack epoxy?

if you just torque up the manifold to the head with no gasket, can you see any deformation of manifold??

perhaps a larger flange face on the inlet manifold could be used (ie, retain the excess material between bolts) to give it more stiffness?

[oldcorollas]

what about this kind of thing?
http://www.farwestcorrosion.com/ccp/flange/psi3.htm

http://www.pikotek.com/Products/default_old.asp

2mm thick metal gasket, with 1mm stepped grooves?

trojan seals http://www.apsonline.com/gasket.html

metal seals? http://www.ultra-seals.com/metal_seals.html

industry regularly need seals that deal with a few thousand Psi.. so 30-40is no big deal

perhaps enzed or pritek could not give advice, but looking around industrial setips for sealing face/flanges, shoul dgive a few ideas...

no idea on custom made trojan tope seals, but maybe something can be approximated (ie, 1mm ring on either side of 2mm metal gasket etc...

[30psi 4agte]

oh i would never use an o-ring without metal on both sides... it will squeeze out and suck in if not restrained...


hmm.. grey loctite fuel resistant 2 pack epoxy?

if you just torque up the manifold to the head with no gasket, can you see any deformation of manifold??

perhaps a larger flange face on the inlet manifold could be used (ie, retain the excess material between bolts) to give it more stiffness?

Ahh i think u miss understood me here. Imtalking about a complete gasket cut out from a sheet of rubber say 2mm thick.

hmm.. grey loctite fuel resistant 2 pack epoxy? What about just welding the manifold to the head for the ultimate seal !!

As far as the flange face idea --- yeah i know !! I have been talking to the guy who made the plenum for me about the cracking issue i have with it. ( can see pics of the mods i have just done to stop the cracking in my members rides thread) and if what i have done doesnt fix the prob we are going to build a completely new plenum, one with 3mm wall runners that are not welded to the plenum or manifold flange.
We are going with an o-ring seal floating runner setup.CNC 20 mm thick flange plate etc etc if i end up going this far i will surley have the flange machined with grooves to seal it to the head !!!

[allencr]

YES, it's certainly braced well, and I take it that the studs aren't loosening up too much, so its probably shaking enough to compress the gasket & then blow past it.
Has just sealant without a compressable gasket been tried?
I'd try beveling or rounding the edge of the port, in the head and manifold, so there will be a nice little 1-2mm 'V' that some flexible RTV will fill & won't get blown thru. Like makeing your own O-ring in place.

[30psi 4agte]

No havent tried with no gasket and just sealer. I dont see it working but havent tried it.

Do you think RTV is that strong it will hold that sort of pressure ????

[oldcorollas]

full rubber would get blown out/sucked in i think, esp if any oil got under the surface... slidey!!

as for bevelling the edges... it also has to withstand vacuum, so it could get sucked in

RTV just between metal surface could work, but if it squeezes out inside, you have blobs of it there... perhaps...

whatever you do, it has to work for both pressure (2atm, and vacuum (1atmish)

i like the metal seals above with rubber on either side, but dunno if you can get them/make them to such a custom shape?

[Jasper]

Loctite 515 FTW

Loctite 515

[fixeruperer]

get a spare head get some 4mm ally plate trace a gasket cut the gasket shape out, throw the shape away, place the ally over and around the ports, cut out injector grooves weld it up clean it up make a big surface area make new flange for inlet manifold.
and hey presto a massive sealing area or enuff area to place orings or wat ever you want.
TO THE EXTREME