Author Topic: Vacuum hose quesion. (Read 5720 times)

Thurber · « **on:** June 14, 2009, 05:17:18 AM »

I ordered a meter of vacuum hose from pelican parts and it seemed awfully flimsy. Perhaps I don't understand things correctly but I heard that vacuum hoses were supposed to be super stiff so they don't collapse... or something like that. I was wondering if anyone could clear this up.

Also, what's the deal with Samco's products? Is there any upside to using "performance silicon hoses" aside from, I assume, reliability?

Thanks!

HATER-PROOF · « **Reply #1 on:** June 14, 2009, 06:48:54 AM »

pelican parts is where I made my first mistake(opinion alone)-but yes you're correct, they are supposed to be stiff, any-time I have to replace something in my engine, the first thing I will try to find out is if I can find a performance version. In the US Army we have a saying "you can always add to, but never take from" Buying from PP will be taking away in my book(my opinion). Samco products are very durable and cool looking for engine bay dressing.

Jorgeconrico · « **Reply #2 on:** June 14, 2009, 08:00:59 AM »

Same thing happened to me when i ordered from pelican parts. I needed a piece of vac hose bc i was replacing the maze of hoses under the intake and deleting the TB heater plate. Pelican Parts sent me some some sort of fuel line that was cloth braided??? I dunno, i ran it from the valve cover to the TB because i don't think that hose is under heavy vac. I've had no problems so far.

DesktopDave · « **Reply #3 on:** June 14, 2009, 09:52:47 AM »

I've had pretty good service from PP, but I haven't ordered vac line from them. I was confused by their web site, so I'll probably just go and order bulk hose and do it my way. I love their 'projects' list, really keeps me focused on one thing at a time.

Thurber: Silicone is a superior material in every way. It can take more pressure, more abrasion, more colors, more expensive. Samco has a good reputation, they're pretty easy to get and they stand behind their products. Having said all that, silicon is overkill for our cars unless you're boosted IMHO.

Silicone sure looks nice though. I'd be tempted to spend more on red hose and nickel-plated t-clamps than my car is worth.

Thurber · « **Reply #4 on:** June 15, 2009, 12:47:58 AM »

Hm... I think I understand. I also bought the hose from pelican parts when relocating the ICV Jorgeconrico. I started my car up today and checked out the hose--it was definitely collapsing in on itself. I don't like the likes of it. I can't find sturdy vacuum hose large enough locally. Would coolant hose work well enough. I don't really want to spend that much money on 1/2 meter of tubing. I just want something that works correctly.
Where did you guys get your hoses?

Jorgeconrico · « **Reply #5 on:** June 15, 2009, 07:34:33 AM »

I'm using 5/8" heater hose/coolant hose from pep boys from the intake manifold to the ICV, as well as, from the ICV to the intake boot. IIRC the previous hoses are under vac. The heater hose seems to be working fine for now ( driven about 200 miles), but I'm eventually going to replace these hoses with some heavy duty vac hose. The hose i got from pelican is being used from the valve cover to the TB and seems to be doing the job.

DesktopDave · « **Reply #6 on:** June 15, 2009, 11:13:23 AM »

I'm thinking about permanently replacing those hoses with silicon. I like the look of it, just have to find a decent supplier. Sure, it's expensive (but I like matching red hoses). Call me a ricer if you will, but silicone is a far superior material.

beemer1 · « **Reply #7 on:** June 15, 2009, 12:14:01 PM »

I am using heater hose for vacuum as well and no problems after ~1,500 miles.

The only thing you may want to watch out for when deleting the TB heater is the hose that connects the black plastic pipe to the head. Regular heater hose will eventually fail b/c it is temp rated for coolant and this particular section of hose will be close to the block/head, in which temps will be much higher than coolant temps. I found high temp heater hose at a boating store on the cheap!

Steve

Thurber · « **Reply #8 on:** June 15, 2009, 03:09:48 PM »

Alright. I have some leftover 5/8" heater hose that I will use until I have some "spare" cash to get some quality silicon hose. Thanks for your info.

Jimmy Lewis · « **Reply #9 on:** June 16, 2009, 12:39:04 AM »

A great alternative to the 5/8 vac hose is 5/8
water line at any boating store. Much more rigid strong than fuel hose, though it works great in the places that see the most vacuum like the ICV to the manifold and such, where a straight piece is fine. The price to necessity of silicon over rubber isn't worth it for me. These are old cars, whatever works.

Thurber · « **Reply #10 on:** June 16, 2009, 01:01:22 AM »

Damn I might be able to find 1/2 a meter or so of Water line at my job. I'm going to definitely check that out tomorrow.

3bvert · « **Reply #11 on:** June 16, 2009, 02:07:06 PM »

I have not had bad luck with pelican parts, however for vac hose I too adn using heater hose

beemer1 · « **Reply #12 on:** June 16, 2009, 06:53:42 PM »

I just completed a +700 mile trip in 9 hrs 45 mins and the car is strong like bull! Kinda like a cannon ball run, jk. It runs nice when there are no vacuum leaks

A Valentine 1 helps too

Steve

Thurber · « **Reply #13 on:** June 17, 2009, 12:40:23 AM »

Good I don't need to do anymore work then. I couldn't find and water line at my job anyway. I've finished replacing my coolant and vacuum hoses, I'm loving that I don't have to worry about it anymore.

Wayne at Pelican Parts · « **Reply #14 on:** June 17, 2009, 11:34:12 AM »

Quote from: Thurber;73595

Perhaps I don't understand things correctly but I heard that vacuum hoses were supposed to be super stiff so they don't collapse... or something like that. I was wondering if anyone could clear this up.

Hello all. There seems to be some slight confusion on this topic. Vacuum hoses for these cars are not necessarily supposed to be stiff. The strength of vacuum hose is primarily measured by the wall thickness of the material, not by how stiff it is. It is this wall thickness that prevents "collapsing" under vacuum.

The vacuum hose that we sell is spec'ed out to be the same as the original OEM hose that was used on the car when it was manufactured. That is, of course, if the correct hose is ordered. Some hoses are thicker than others and thus will withstand the "collapsing" effect better than others. If you order hose in bulk, or order it without considering the outside wall thickness, then you might have a problem with the hose collapsing under extreme vacuum. Also, if you use fuel line, then you may be in trouble too. High pressure fuel line is supposed to withstand pressure pushing outwards. As such, it is often reinforced with fibers within the rubber hose. These fibers help to reduce flexing and bulging under pressure, but they will do very little to guard against the hose collapsing.

The outer cloth braided hoses we sell are the same material that was used on BMWs and Porsches for the past few decades. An example of this is the power steering hose for the 911SC - it's cloth braided and flexible, but it also has a very thick wall so that it will not collapse. These same cloth braided hoses can be found all over the entire engine compartment of a 911SC or an early E30 BMW. In later years, with the E36, BMW went to a less-expensive all-rubber design. I discuss these types of hoses and their applications, along with photos of what they look like in my book, "101 Projects For Your BMW 3-Series". There's also more info on it in the Tech Articles section on Pelican.

Now, on more modern cars, they've been starting to get away from the rubber lines and go with hard molded plastic in some cases. On the Posrche 996 / Boxster and newer BMWs, many times a vacuum line will now be molded and pre-fabbed to fit into the shape it is supposed to occupy within the engine compartment. I'm guessing that these hard-plastic lines are cheaper to produce than the rubber vacuum hose. It's too soon to tell if they will be more or less durable than the rubber ones. So far so good from what I can tell though...

Still, your question here brings up an important point in that we should be educating our customers on the proper ordering of vacuum hoses from within our catalog. I will have my catalog content manager revise the catalog to include the information here so that there will be less confusion in the future.

Thanks everyone for your continued support!

-Wayne

Wayne R. Dempsey
CEO, Pelican Parts Inc.