Partially blocked crossover vent

cartfreak71 · Posted: Thu Oct 01, 2009 1:24 pm Post subject: Partially blocked crossover vent

On the tank for my 72 CB350, as I was treating it with POR-15, I noticed that the cross-over vent next to the petcock is partially blocked. I haven't poured in the actual sealer yet of the POR-15, just the first two steps. My concern is that because the blockage is in an area that I can't get to, will the sealer make it fully blocked. I've thought about putting a piece of wire or something in the vent to keep it open and then remove it later. I'd like to be able to finish sealing it this weekend so I can start painting it next week.

Thanks for any suggestions.

Blue · Posted: Thu Oct 01, 2009 4:01 pm Post subject: blockage

I'm not real sure, but I would clean out the residue that is there and put something in to keep it from closing up, a proper size wire or a small rubber tube or something, maybe someone else will add to this, but for me I would want max. flow.........Blue

dorT500 · Posted: Thu Oct 01, 2009 5:11 pm Post subject:

Is the link below similar to the problem you have?....If so I was thinking just off the top of my

head, that a wire or maybe even better ..maybe a short length of an old control cable

chocked up in VARIABLE SPEED drill would remove some of the blockage. Seems like the frayed end might do

a number on some old rust/varnish with a little solvent mixed in there from time to time. Just go real easy at

first...a little at a time. Then something the the right size greased up so the Por 15

won't stick to it? Idunno

Here is what one guy did....Might want to get some other opinions on it...

About the 27th group of pictures and text down from the top of the page...

http://jaredyates.com/pages/cb350/cb350.shtml

Blue · Posted: Fri Oct 02, 2009 3:12 pm Post subject: yeppers

I like the cable idea, flexible and would grab stuff and extract it, it would be kinda like a roto-rooter for fuel tanks, maybe a patent is in order, there is a gun cleaning string type device that works similarly, brush in the middle and string off both ends you push it through and "saw" back and forth, till the bore is clean........Blue

cartfreak71 · Posted: Sat Oct 03, 2009 12:08 pm Post subject:

I've able to get the hole opened up to at least 1/8". Almost seems like the bend in the tube is where the constriction is, but not blocked by rust or anything, just by the shape of the bend. I'll work on a little more today, but it does have better flow now.

tbpmusic · Posted: Sat Oct 03, 2009 12:14 pm Post subject:

You should try a guitar string - one of the large wound strings from an acoustic guitar.

I use RedKote myself, but run into the same problem with 350/450 tanks.
I usually give it a couple of blasts of compressed air several times as it sets up, then use the guitar string.......

cartfreak71 · Posted: Sat Oct 03, 2009 3:37 pm Post subject:

Success! Got it unplugged. Ended up using two pieces of throttle cable together and used them like a round file. Only took a few minutes. Really good flow through it now. POR-15 sealer is in the tank now. I will blow air through each of the crossover vents a few times over the next few days to make sure they don't plug up. If they do, at least I have a good method of getting them unplugged. Once the POR-15 cures (4-5 days), I can start painting the tank.

hondacl360 · Posted: Sat Oct 03, 2009 8:53 pm Post subject:

i used the por 15 on my tank in may and i had a similar problem , check that cross over after a couple of days of drying . i ran a small wire through mine , but the por 15 worked great

cartfreak71 · Posted: Sun Oct 04, 2009 3:31 pm Post subject:

tank has been curing for almost 24 hours and the crossovers are still opened all the way.

dorT500 · Posted: Sun Oct 04, 2009 5:20 pm Post subject: Re: yeppers

Blue · Posted: Mon Oct 05, 2009 1:06 pm Post subject: Hmmmmm

That looks pretty serious, I think that a piece of 3/8" steel cable untwisted to the configuration you show might do it, but if there are any weak spots, that'd be it for the tank. I did have an idea about partially filling the tank with, broken glass chunks from bottles, and then wrapping the tank in foam to keep it protected while it tumbled, but the wife negated the idea, when she found out I wanted to use the dryer, couldn't even convince her if I did it on the "cool down" cycle. Of course she isn't home all the time!! I got the thought from a woodworking show where the guy broke some bottles to scrape finish from a chair, accordingly the glass always yields a piece the right shape to get into tight areas..........Blue