Well, there really isn't much evidence that the silicon hoses will outlast the stock rubber hoses, since most people haven't had them in long enough. That said, I'm sure the silicon hoses will last a long time. However, it's been proven that viton is a far superior material for this application -- it resists kinks, resists oil and gas, and has much greater tear resistance.

There is a downside. Buying all the viton hose required for the hose job will probably cost you $500+ from McMasters. I have read that Pettit sells Goodyear's version, it's probably cheaper.

 

McMaster-Carr: http://www.mcmaster.com/
(search for viton tubing - they use frames so no direct link)


you have to get english unit hoses to get the thicker-walled hoses (1/8" thick, not 1/16" thick). The thinner walls cannot withstand the vacuum levels required.

 

What's difference (besides price) between 60A, 75A, and 90A?

 

Takes about 3 hours if i have to take off the UIM and all the other crap.

 

Those are the durometer ratings -- how hard the material is. I can't remember off the top of my head if you are supposed to get the 60 or 75 durometer. Read that report on geocities posted earlier in this thread.

 

Hardness of the material relates directly to flexibility of the hose. The 60 is what I bought. The 1/8" ID, 3/8" OD has to be able to slide over the "bumps" on nipples that were made to take 3.5-4.0mm ID hose. 1/8" is 3.17 mm, so it's a really tight squeeze where Mazda has used the bumpy nipples. I bought 50 ft of the 1/8"ID, and 15 ft of the 1/4" ID, 1/2" OD stuff from McMaster-Carr and the price including shipping was $543.57. I've only installed one piece of the 1/8" ID so far, as a test; the line from the intake manifold to the Air Bypass (blow-off) Valve. The nipple at the manifold was a perfect match, but the nipple on the bov was very tight because of the bump.

Note: The 1/4" ID stuff is to replace the 6 mm ID OEM hose; 1/4" = 6.35 mm, so I expect that size to be a little loose. Hopefully the clamps will take care of it; I haven't tested that yet.

---- Bill

 

I used the 75A. They are flexible enough. I found the 60A colapse easily, plus I bought the regular thickness not so 1/8 ID with 1/8 wall, not 1/4 wall.
Too expensive for the 1/4 wall.
I did some testing with vacuum pump. It did not colapse at all.
As with regular silicone hose. Try not to have tear on it. I squeeze one with a plier, and it break after 2 days.

Reza

 

BUNA-N is cost effective ,silicon splits and gets soft with gas and oil , kids like the colors, viton is best but high dollar. None of Garfinkles customers with buna -n are complaining about performance or cost.

 

from McMaster-Carr:

buna-N is only rated for up to 212 deg F and is not pressure rated

These two statements do not sound good for using it as a vacuum tube material...

 

Reza,

I tested my full 50-ft length of 1/8" ID, 1/8" wall thickness (3/8" OD) Shore 60 Viton hose using my MityVac Silverline Plus. It withstood all the vacuum I could generate, about 25" Hg, and did not collapse anywhere along its length. I also tested my 15-ft 1/4" ID, 1/8" wall thickness (1/2" OD) hose (also Shore 60), and it was fine too.

---- Bill

 

Would have taken me 5 hours except that I broke one of the nipples and had to bum a ride and go to various friend's homes to get a spare solenoid.

By the time I got back it was too dark and I just waited to finish it the next day.

 

Bill,

Oh ya, forgot to mention how I tested it.

1. I took about 3 inch length.
2. Loop it to form 1 to 1.5 inch circle.
3. Preheat oven to 300F
4. Put in oven for 5 minutes.
5. Take it out
6. Then vacuum tested it.

I found the 60A is flimsy, it still form correctly, but when I bent it more from 1.5 inch loop to 1inch, it got kink. When it got kink, I test vacuum it, then it won't flow any air, so the kink make a close end in it.
The 75A does not kink.

This is my own strange testing to simulate engine bay environment, and close loop.
I do not think there will be loop with radius 1 inch under UIM.
I have not done my vacuum hose job yet. So I am inexperience. I have replaced some though.

Reza

 

Reza,

Thank you for describing your test conditions.

Sounds like you ran a good test, but I do not consider this hose "flimsy." I will take your advice and keep my loop radii reasonable, by using double loops if necessary.

I did blow through the 1/8" ID hose at room temperature with it bent into a "U" shape, with the outsides of the "U" less than 1" apart, and the insides of the "U" practically touching, before it kinked and closed off the air. Another test would be to form it, heat it for a while, and then try & blow through it without moving it at all, both at high temp and after it cools.

I do think the force required to press 1/8" ID hose over Mazda's nipple "bumps" will be too high with the Shore 75 material. It's already very high with the Shore 60.

---- Bill

 

how many people did it while their engine was out, or pulled it out to replace the hoses... those who anwered 'me' or 'yes', did you replace anything else while you had the engine out? getting answers like this would help people to be able to plan 'major work days'.... although then again, doing more than one mod at a time might not be such a good idea...

 

The vacuum job is not that bad, just tedious. It took me 2 days the first time I did it. The most recent (5th time) it took about 5 hours.

I want to add a few tips:

1. print out a color shop diagram AND the black and white version (not just a greyscale of the color though). I believe there is a copy of both on Max Cooper's site.
I regularly cross referenced them to connect the hoses on the rack itself. Generally the B&W diagram is much easier to follow than the color because it's about 2 times the size.

2. Use a pen to check off each hose you finish on the B&W diagram. if you want to be really **** you can even color them in as you go.

3. use a hairdryer or other heat source to preheat the hoses that you are removing from the plastic solenoid nipples. They flex much easier and the plastic won't be as brittle when they're warm.

4. if you're having trouble getting an old hose off a solenoid try pushing the hose against the nipple stop rather than pulling it. It is counterintuitive, but generally this will cause the rubber to bunch up and bow out from the nipple thereby breaking the seal. After that you should be able to rotate it freely and just slide it off.

5. If you have no reason to believe you current setup is incorrect, tape numbered tabs to the nipples on the back of the solenoid rack. The diagrams are extremely confusing in this area. I would have reinstalled mine incorrectly if I had just followed the diagram.

6. While you have the stock airbox out throw away those goofy spring clamps on intake hoses. I probably spent 20 minutes trying to reconnect the lower one using vice grips. Worm gear style clamps are much better to work with.


Hope this helps,

Chris C.

 

That deterioration of the silicone doesn't suprise me too much. The original owner of my car used some silicone coolant hoses for the intercooler couplings and after about a year they were falling apart like the silicone lines in that test showed

 

2 days. All weekend.

If you have a digital camera, take pictures. Take notes of each step and install in reverse order.

 

Garfinkle puts a small flar on the metal lines and uses zip ties. you cannot pull a line off with out ripping it.

 

McMaster Carr (mcmaster.com) It's not cheap, but I rest better knowing that it won't disolve. The hose job only took me 2-1/2 hours (with the engine out of the car ) Hint #1: Replace just (1) hose at a time. Hint #2: Gently squeeze the hose where it is attached to the solenoids with needle nose pliers, all around the circumference prior to pulling them off, this will break the bond a little and make it easier to remove. I started trying to use the exacto knife bit, but the damn hose's are so hard that it took more force to try that than the plier trick. It also helps if you get one of those reverse plier tools (as you squeeze, it spreads), use it carefully and it will save you a bunch of time as well. Hint #3: Be patient, haste makes waste, and may cost you a nipple or 2 (I didn't break any, whew!) Good luck.

Regards,
Frank

 

Frank,

Could you explain how and where to use the spreading pliers? Is that on the new stuff, to enlarge the ID? Thanks!

---- Bill

 

No, just to help slip the hose off of the nipple. I put one side against the solenoid and the other at the end of the hose, then gently squeeze to push them apart. I would use it in different locations for the same hose so as to not put to much uneven pressure on the nipples. This works good, but be sure to use normal needle nose pliers and gently squeeze the perimeter of the hose to loosen it's grip.
Good luck,
Frank

 

Got that; thanks, Frank.

---- Bill

[P.S: I like those gauge pods!]

 

ok tell me if i'm getting what I need before I order this stuff, and please let me know if it will work or if i should modify my order.

-15' High Temperature Viton Rubber Tubing Hard, 1/4" ID, 1/2" OD, 1/8" Wall, Black
-50' High Temperature Viton Rubber Tubing Hard, 1/8" ID, 3/8" OD, 1/8" Wall, Black


do i really need 50 feet? and also what kind of clamps should i get? zip ties or what? where?

 

bump I want to order tonight

 

anybody? i don't wanna start a new thread for this question