I'm closing in on doing the complete hose job. Most of it is 3.5mm tubing. But, I can only find 1/8" and 4mm tubing in Fluoroelastomer. No 3.5mm.

I've checked grainger and mcmaster with no success. Also, searched and google'd to no avail.

Does anyone know where I can get some 3.5mm ID viton hose?
Or, can I just tough it out with 1/8" ID?

Thanks,
Barban

 

Read my post on vacuum lines -

https://www.rx7club.com/showthread.p...ht=vacuum+hose

IMHO, viton hose just isn't worth it. Use *good quality* silicone vacuum hose and you'll never have a problem with it.

Dale

 

...thinking about doing the 3.5mm in Silicone and everything else in Viton...

 

Go with the Viton....you WON'T be disappointed.

 

Hose Techniques and Baker Precision have gone ****-up, so yeah...it is VERY hard to find 3.5mm i.d. VITON these days. Web searches show several Chinese companies offer it but...who knows what you'll get? Probably cat-gut or something....

 

If anyone has any extra 3.5mm viton laying around pm me? I know you ordered too much.

 

I have been using Gates brand 5/32" vacuum line from CarQuest for several years with very good results. It has good resistance to most everything, remains pliable, doesn't take much of a set and its inexpensive. I've tried to determine its composition; however, I'm told that it's some sort of proprietary blend.

In any event, this stuff has worked so well that I don't even bother with the Viton anymore for most applications. I wouldn't recommend silicon.

 

mcmaster.com

 

part number 5119K41

should fit fine for most of the vacuum lines

 

The wall thickness is probably not sufficient.

cf. https://www.rx7club.com/showthread.p...wall+thickness

If I ever do a hose job again (which I will only do if I get a new FD because I suspect the Viton on my current car will probably last indefinitely), I will use Viton - purely because it is great to work with and grips the hose barbs like a ****.

The labour is the real cost of doing an FD hose job and it is nice to get the sense that these hoses will not come off and and are so overspecified that they will effectively last for the life of the car.

 

exactly.

 

Please, read my post linked above. For most of the vacuum lines on the car that never see oil there is NO GOOD REASON to use Viton hose. It costs more, it's harder to work with, and you don't get the benefit from doing it.

I have been using Hose Techniques hose for about 10-15 years. I have NEVER had a single failure with their hose. Fits great, looks great, works great, priced right.

Also, Hose Techniques is in business, regardless of the above post. They don't sell Viton hose any more, but they do sell silicone.

All the bad rap on silicone hose came from ages ago when people used cheap, thin wall tubing. It didn't fit well, it split/swelled, etc. I've seen it before. Just get the good stuff and you're done.

Dale

 

^+ 1
Yep, I grabbed a HT vac line kit from Jason @ rx7store.net, he had it cheaper then buying directly thru HT. I've decided since everything under my UIM is trashed to go non seq, so I'll have some extra when I finally get to running the vac lines.

Oh ya, I originally tried to source Viton lines but just gave up trying to find 3.5mm lol.

 

Hell...if you aren't going to use Viton, just go with normal butyl rubber. Far better than silicone, even the 'good stuff', as has been proven repeatedly in nearly all the endless debates.
Right?

Hey, does anyone have an opinion on dino versus synthetic oil...lol!

Dale is a bonafide FD guru so his opinion is something to listen to, for sure.
And fawk me if I can find the damned Chinese 3.5mm VITON listing now....

Nevermind...here is one:

http://www.pt5-sourcing.com/V1/product44.html
http://www.pt5-sourcing.com/upload/f.../fkmmpdata.jpg

 

Barban, read this:

 

Don't try to confuse me with the facts. My mind is made up!

 

I know what you mean, sometimes there's way too much information around here, some true some false. But it is a good read just the same.

 

Update

I just recieved my viton tubing from mcmaster-carr.
55ft of 4mm id
16ft of 6mm id
4ft of 8mm id
$276 after tax and shipping


My concern at this point is that all the tubing has a wall thickness of 1mm and it's really easy to kink. Is this normal, or did I order the wrong material? It's way more obvious on the larger diameter stuff.

 

The old HTS stuff had a wall thickness of significantly more than that. I can check some of my leftover hose pieces this evening.

 

That's REALLY thin for wall thickness. Tight bends to solenoids will definitely kink on you.

Again, Hose Techniques. Hear me now and believe me later .

Dale

 

LoL! Don't tell me you told me so!
It looks like the small stuff will be ok, but the 8mm is pretty sketchy.

It looks like I can get thicker walled Viton if I switch to imperial measurements.
5/16" id, 9/16 od == 8mm id, 14mm od, ~3mm wall thickness
1/4" id, 1/2" od == 6mm id 13mm od, ~3mm wall thickness

Here's the catch, though. This stuff is baller status.
Both are about $14/ft.
Pucker up.

I'm going to see if I can switch the stuff out with mcmaster-carr. If not, I bite the bullet.

 

I'm in the middle of replacing all of my vacuum hoses and would like to know which hoses should not be done in silicone. What hoses might see oil and should be done in something else?

 

No worries.

The PCV line definitely sees fuel vapor.
I would consider doing the turbo control lines in Viton since they're imperative and mine are pretty oily/grimey.

Hopefully a more vacuum-diagram-literate member can suggest some other lines. I'm still kindof a rookie in this regard.
________________
As an update, I returned the 6mm and 8mm lines to mcmaster in exchange for the thicker ones I mentioned. Pretty painless since I just turned the same box around at FedEx.
I looked and looked for thick wall 4mm material, but I can't find anything in Viton. I'm not super concerned with it, since at such a small id it's pretty sturdy with a 1mm wall.
I found some 1/8" id material with thicker walls, and that might fly on the 3.5mm stuff, but probably wouldn't be large enough for the 4mm lines.

I'm acquiring solenoids and such and expect to have this done and documented within 2011(LoL!)
Not, that we're at a lack of vacuum hose write-ups, but I'll probably post the final budget for the hoses, snap some pictures, and post them up here for some one's future reference.

 

The only lines I have in Viton on my car are the lines going from the oil fill neck to my catch can. I did run those with silicone for years with no problems, but I got a good deal on some leftover 6mm Viton from a club member.

Those are really the only lines that see a LOT of oil. Everything else is minimal. Again, you won't have any problems with good silicone vacuum hose.

The lines that do see a lot of oil (PCV lines) you can easily run silicone and just know that in 2 years or so you'll probably be needing to replace them. If those lines fail you'll just get a bit of an oil mess, that's it.

The PCV system should be updated to the '95 style (search on this) where you eliminate the PCV valve and cap off that nipple on the upper intake manifold and oil fill neck. With that done you just have one nipple on the oil fill neck that goes to a metal pipe which then goes to the primary turbo inlet duct. Even better is to get a vented catch can and run two hoses from the oil fill neck to the catch can - keep all the mess in the catch can and out of your intercooler pipes and turbos.

If Viton hose is really $14 a foot, you can replace oil-soaked silicone hose MANY times over for that price. And, again, there's only the PCV hoses that see any substantial amount of oil.

Dale

 

McMaster carries 1/8" Viton with 1/8" wall thickness, that really should work fine. Do people order the soft or firm durometer stuff?