Vacuum Line Confirmation

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Trapper50cal

Trapper50cal

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So Chunk is only pulling 14 in/Hg at the manifold...So I'm going to replace all the vacuum lines in an effort to boost that number a little (for better brakes at the booster)

This rig is still in possession of the whole spaghetti factory (not desmogged)

I have been doing some research (of my own posts even) and I need some confirmation on a couple questions:

Amount of 3mmID needed: 55-60ft?

Amount of 6mmID needed: 7-10ft?

Back in the day of my desmogging Ingrid, Carr McMaster offered 3mm and 5mm but no 6mm and people (myself included) were getting the 5mmID stuff in place of the called-for 6mmID and just stretching it on. Now, it seems, Carr McMaster isn't offering 5mmID but IS offering 6mmID.



So, I'm assuming the thickest wall (3mmID/8mmOD) #5041K52 Semisoft Shore A70 is what I'm looking for to use for the 3mm vacuum lines...

Correct?

And the thickest wall (6mmID/10mmOD) #5041K74 Semisoft Shore A70 for the bigger? Or should I try to stretch 4mmID/9mmOD?

Any input on the lengths and types/sizes? It's my understanding that the Semisoft is the most rigid of the three offerings and desirable but the semisoft and soft both can withstand the same amount of psi (which is obviously the opposite of vacuum in/Hg)
 
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Just my .02, but I hate that silicone tubing. I pulled all mine off and went back to the OE Toyota stuff. You can buy it in bulk and cut to fit for not a whole lot more than the mcmaster stuff.

There are some threads with part #s.
 
Spike Strip said:
Just my .02, but I hate that silicone tubing. I pulled all mine off and went back to the OE Toyota stuff. You can buy it in bulk and cut to fit for not a whole lot more than the mcmaster stuff.

There are some threads with part #s.
Click to expand...

Do you hate it because it breaks when you remove? or because you've experienced collapsing?
 
Neither, though the tubing is very tight and sticky on the pipes.

I kept getting blockages in the sil tubing and I was very very careful to clean everything when I put it all back together after the engine rebuild and used new silicone tubing.

Blew out the spaghetti pipes with carb cleaner and compressed air numerous times. Cleaned everything the vac tubes connect to ... But I kept failing smog, and each time I'd have to go through the emissions system again, and I'd find different blockages in the sil tubing. That wasn't the only reason I failed smog, but the blockages were just one more hurdle... Don't know if I had a dirty system or there's some electrostatic property of the tubing that attracts crap. This was over the course of 5 years... Anyway, after I switched back to the OE tubing for the last smogging, no more problems.

:meh:
 
J,

I bought 40' of 3mm and 10' of 5mm, they didn't have 6mm at the time in BLUE for Marley.. I had a little of each leftover. It just depends on how tight you run the lines. I pulled each old line, cut the new, and installed... etc...

http://www.boostcontroller.com/index.php?category=8

^^ was the cheapest for PURE silicone hose at the time I bought it. Never had an issue with my hose from them.

J
 
In a pinch, Bap Geon (if there is store located near you) carries braided line, but it is probably more expensive:

Continental Contitech Braided Hoses (Bap Geon)

3.5 mm ID - Black - part#N203531-5 (for smallest vac lines)
5 mm - Grey - part#?
7 or 7.5 mm - part #?
9mm - Black - part# N-20376-20

The 3.5 mm is a good fit for the smallest ID vac hose. I had some issues with getting the 5 mm to fit (but forced it to fit); the local store didn't have any of the 7/7.5mm in stock.

My apologies for the incomplete (and possible not 100% accurate), but even the guys at Bap Geon who were giving me these numbers couldn't get it right. It was one of those situations where I was just testing the different sizes they had available to see what would work where on the truck and going with it...
 
Trapper50cal said:
Hey, Ryan!!! Like the new Banner!
Click to expand...

Thanks, I'm all over the place lately, questions here, design there, rebuild the website 3 times. I've been meaning to make a different banner,

JT don't break my truck! hahaha ;)
 
reevesci said:
J,

I bought 40' of 3mm and 10' of 5mm, they didn't have 6mm at the time in BLUE for Marley.. I had a little of each leftover. It just depends on how tight you run the lines. I pulled each old line, cut the new, and installed... etc...

http://www.boostcontroller.com/index.php?category=8

^^ was the cheapest for PURE silicone hose at the time I bought it. Never had an issue with my hose from them.

J
Click to expand...

Thanks, J:beer:
 
I think I bought 42' and 10' from McMaster Carr and had a good amount left. I wasn't to fond of the 6mm stuff, seemed thin. This is a great way to find out how many things are hooked up wrong! I think the mechanic that the PO took it to just kinda made up his own rules.
 
reevesci said:
Better hurry up Ryan! I'll talk him in to coming up to do the paint and body by the end of next month!!

:D

J
Click to expand...

QUICK EVERYONE BUY THINGS FROM ME! I've got lift kits and bumpers to sell! (everyday I'm hustling) hahaha :lol:
 
I bought the same stuff that J did from boost controller and have not had any issues. I bought 35' of the 3mm and 15' of the 5mm and still have some left over of each to replace lines here and there. But then again I am desmogged so you will need what J said for a smogged rig.
 
Just ordered 50' of Black 3mm and 10' of Black 6mm from BoostController

and new BVSV #1 and #2 from Beno, along with a new Brake Booster Check valve.
(BVSV's just in case I break one and check valve for cheap insurance that it's working properly.)

So, hopefully. All new vacuum lines, Check valve and a engine valve adjustment will bring my Inches/Hg numbers up at the manifold.
 
What elevation are you at?

Post #11 on the following thread took manifold vac measurements at sealevel (20-21 inHg) and at 4000 ft. (18-19 inHg):
https://forum.ih8mud.com/60-series-wagons/597731-what-your-intake-manifold-vacuum-inhg.html

So at 14 inHg even at elevation, if that guys measurements were accurate and his rig was operating well, then it sounds like you could make up a couple of inHg.
I recently took the same approach you are, starting with the easy stuff (vac hoses) and am up to 21 inHg. But still have the intake/exhaust manifold on my to do list (reving the throttle exposes a vac leak)...waiting for the weather to break...
 
I'm at 7200ft in Pagosa Springs (Town proper is a couple hundred feet below where I live)

I'm planning a valve adjustment after all the lines are replaced. At that time, we are going to check the HAC to see if it's still
providing the extra advance that it should be. If it's not, we're going to build some advance into the base timing and retune.
 
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7,200 ft. that's up there!

Just out of curiosity, do you have the HAC vac line hooked up to the inside or outside vac advance diaphragm on the distributor? Is the rig fully smogged?

I think I read somewhere that at sea level, the vac advance from the carb is routed to the inside diaphragm and the HAC to the outside one. Then at higher elevations there might be some advantage to switching them? Don't know for sure, I could be completely wrong here, but for some reason that stuck in my mind.
 
I'd have to look, but I'm guessing outer as that's the secondary advance port and the inner one is the primary that goes to the carb.

The truck is still fully smogged, with one caveat...the smog pump has been gutted (vanes disintegrated) so it isn't blowing any air...which
makes me wonder if that's causing any negative vacuum issues or EGR issues also...but one thing at a time.

Here's what I know about the HAC...



But if it's inop or not working properly due to vacuum leaks then I'm missing out on some portion of 7º-8º of advance. Which, I'm led to believe, can adversely effect manifold vacuum as well.
 
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