Author Topic: When putting an old tank back on the road  (Read 1391 times)

0 Members and 1 Guest are viewing this topic.

Offline dustyc

  • I don't know why anyone would call me an
  • Expert
  • ****
  • Posts: 1,141
  • 1977 CB750K
When putting an old tank back on the road
« on: September 28, 2007, 06:25:18 AM »
I used a tank that came off a bike that had been off the road for 12 or so years.  I cleaned the petcock completely spotless before I ran the bike and did a couple of rinses with fresh gas.  Then ran Seafoam in the first few tanks.  I've been running the bike for 2 months now.

Yesterday I did a tank swap and when I pulled the petcock off the old tank this is what I found(plus a little more that didn't make it into the picture).  The bowl was completely full.  I assume this is the remains of the old gas that dried in the tank over that 12 years.

So if you're breaking in a tank that has been sitting for a while, keep an eye on your petcock.  I can only imagine I'll need to go back through my carbs now too.

1977 CB750

Offline smashedmelon

  • Enthusiast
  • **
  • Posts: 135
Re: When putting an old tank back on the road
« Reply #1 on: September 28, 2007, 12:08:40 PM »
keep an eye on your petcock screen regularly, it doesnt take long to shut the valve off and unscrew the bowl. If you get more flakes of rust in there even after you do all that work thats ahead, you still have rust in the tank. Do a search on it here theres tons of info....  and get that tanks innards cleaned up and maybe coated... it'll save you much hassle in the future.
CB750K5, CB750 K3 parts bike, CB750K3 baby-cakes

Offline Geeto67

  • A grumpy
  • Old Timer
  • ******
  • Posts: 2,823
Re: When putting an old tank back on the road
« Reply #2 on: September 28, 2007, 12:26:56 PM »
fresh gas on top of old gas turns the fresh gas sour really quickly. Where as a fresh tank would last 6 months, putting new gas on top of really olf fuel will pretty much gaurantee it won't last 6 hours. 
Maintenance Matters Most

Texwing

  • Guest
Re: When putting an old tank back on the road
« Reply #3 on: September 29, 2007, 06:11:38 AM »
I always add a couple of small inline filters after the petcock to be sure this kind of stuff, and rust, dont make it to the carbs.  Seems to be the norm for lots of old Honda tanks.

Offline dustyc

  • I don't know why anyone would call me an
  • Expert
  • ****
  • Posts: 1,141
  • 1977 CB750K
Re: When putting an old tank back on the road
« Reply #4 on: September 29, 2007, 07:02:08 AM »
I ran inline filters for a few weeks to catch the big things.  This is a sludge that finds a low spot and collects -it made it through the screen in the petcock and doesn't have any grit to it. 

When I took the carbs off about a month ago, the bowls had some gum in them as well.  I didn't think the petcock would be full like it was and just wanted to give a heads up to people using a tank that gas had dried in to check their petcock frequently.  If I hadn't been changing tanks and didn't check it, it would continue to migrate into the carbs. 

Now I know that a thorough cleaning of the tank before installing it would have been a better idea than just a rinse.  And now I know that inspecting the petcock should be part of my maintenance.

Well off to clean the carbs again.
1977 CB750