Author Topic: Few quick Q's 72 CB350F  (Read 2125 times)

0 Members and 1 Guest are viewing this topic.

Offline strangedaze39

  • Hot Shot
  • ***
  • Posts: 372
  • 1972 CB350F
Few quick Q's 72 CB350F
« on: May 15, 2008, 03:44:18 PM »
Hey everyone, so here are the questions.

1) I need to find a replacement screw for my clutch perch, it's the screw with the hollowed out center and a open side. Where could I find one?

2) How do I check if my kill switch is enabled or not? I think the whole reason my bike won't start could be a result of this. I have a circuitry hand light tester should I use this? Or is there anyway that I don't have to wire around it and just hope that makes it start?

3) What size is mm is the petcock thread that goes into the tank? (for some reason i can't find this info on any repair sites for these) How about a DIY petcock? Bad Idea?

4) For some reason my 4th cylinder carb won't drain when I loosen the drain scew. While the 1st one does fine. I'm guessing this is a bad thing?

If someone knows any tricks for starting this bike anything helps.

Thanks for reading  :)
SD
« Last Edit: May 15, 2008, 07:43:05 PM by strangedaze39 »
1972 Honda CB350F

fixahonda

  • Guest
Re: Few quick Q's for getting my 72' CB350F running
« Reply #1 on: May 15, 2008, 04:19:03 PM »
They sell replacement clutch adjuster screws on ebay that are made of brass so they won't rust anymore. Alternately you can get a used on from someone on here.
To check your kill switch, you will need a wiring diagram to find out which wires they are. I think the Black and Black/White wires are the ones you are looking for. They terminate in the headlight bucket. You should have continuity between them when the switch is on. I have seen a lot of the solder joints up in the switch fall off causing the switch to fail.
The petcock is held in by two philips head screws. You can access them if you remove the small bowl, gasket and screen at the bottom of the petcock. You can then either disassemble and clean it, or get a rebuild kit for it (also available on ebay).
The carb drain screws are hollow. If the others are draining when they are loosened, it probably means that the #4 screw is clogged. Take it all of the way out and see if it drains then. If not that probably means your float is stuck up and not letting any fuel in.

Offline OldSchool_IsCool

  • Really feeling like an
  • Old Timer
  • ******
  • Posts: 4,349
  • WARNING: Objects in mirror appear to be LOSING!
Re: Few quick Q's for getting my 72' CB350F running
« Reply #2 on: May 15, 2008, 04:26:37 PM »
Place your test light across your points.  Key on, kill switch on, charged battery installed plug wires removed from plugs (ya don't want it to accidentally START while testing!)

Slowly turn the crank.  The light should turn on when the points open and go off when the points close.  Turn the kill switch off.  Now the light shouldn't light at all.  that should be enough to validate your switch (as well as a lot of other circuit components too!) 
Can I have a motorcycle when I get old enough?
If you take care of it.
What do you have to do?
Lot’s of things. You’ve been watching me.
Will you show me all of them?
Sure.
Is it hard?
Not if you have the right attitudes. It’s having the right attitudes that’s hard.

Offline strangedaze39

  • Hot Shot
  • ***
  • Posts: 372
  • 1972 CB350F
Re: Few quick Q's 72 CB350F edit: Need HELP ASAP (carb issue)
« Reply #3 on: May 15, 2008, 06:14:31 PM »
Good  news, kill switch is fine, I used old schools method and it worked great. What does the kill switch do anyways just stop the bike from creating spark?

Now the BAD news/ semi-good news? I took my float bowl off my carb that wasn't letting any gas through. I did find it was clogged after a lot of carb clean and gentle scrubbing that thing was filling fast and good, and looked a lot better.

Ok so when I did this being an idiot I left the O-Ring that connects the float bowl to the rest of the carbs on. It apparently is now to big by a 1/4 of an inch for it's seating. I tried washing it and letting it dry (not for long) and it got a little better but still won't fit. So this really sucks I have a wrench balancing the float arm up and I can't leave it like that for long. Any suggestions on how to get that O-Ring (gasket) on there?

I read on another forums cutting it and super glueing it back together works fine. Or boiling it and letting it sit in the freezer for a little while shrinks it as well. I tried warm water and fridge with small results. Anyone? I really don't want to leave that float like that un attended. (and my petcock doesn't shut off to top it off  >:( )

Thanks for reading anything will help.
SD
1972 Honda CB350F

Offline OldSchool_IsCool

  • Really feeling like an
  • Old Timer
  • ******
  • Posts: 4,349
  • WARNING: Objects in mirror appear to be LOSING!
Re: Few quick Q's 72 CB350F edit: Need HELP ASAP (carb issue)
« Reply #4 on: May 15, 2008, 06:21:38 PM »
Kill Switch:
Exactly.  The kill switch powers the coils.  When the switch is off, no power to the coils and thus no spark.

float bowl gasket:
Try a little grease to "glue" the gasket into the channel of the float bowl.  I think heat will cause it to shrink (an odd property of some polymers is that they shrink when hot, expand when cold).
Can I have a motorcycle when I get old enough?
If you take care of it.
What do you have to do?
Lot’s of things. You’ve been watching me.
Will you show me all of them?
Sure.
Is it hard?
Not if you have the right attitudes. It’s having the right attitudes that’s hard.

Offline mattcb350f

  • Hardly a
  • Master
  • *****
  • Posts: 1,625
  • 1974 CB350F
Re: Few quick Q's 72 CB350F edit: Need HELP ASAP (carb issue)
« Reply #5 on: May 15, 2008, 07:22:51 PM »

It apparently is now to big by a 1/4 of an inch for it's seating. I tried washing it and letting it dry (not for long) and it got a little better but still won't fit. So this really sucks I have a wrench balancing the float arm up and I can't leave it like that for long. Any suggestions on how to get that O-Ring (gasket) on there?

SD

Same thing happened to me a few days ago  >:( Took the bowl off and the O-Ring had swelled up.

I did However get it back in. Let the O-ring air dry for a bit, this seems to shrink it a little. Then, Set it in the bowl grove as best you can, and gently put it onto the carb. Start to thread the four screws in until the O-Ring is just touching the carb and the bowl. Now, take something small like a tooth pic and begin to "poke" the O-Ring into the slot as you gently push up on the bowl. This takes a bit of patience but I managed to get mine in this way. It helps to give the screws a few turns while you are doing this but be careful not to pinch the O-Ring; use a flash light or trouble light to check.

Also, you are going to want to get that gas shut off somehow, I would use a small pair of vise-grips to pinch the line temporarily or just take the tank off and lay it in a way so that the fuel is away from the petcock.... preferably out side to avoid a spill  ;)

 Matt.
1974 CB350F,  1980 CB125S,  1981 XL80S
Non Honda's: 86 & 87 Husqvarna 400wr's

My CB350F resto: http://forums.sohc4.net/index.php?topic=30467.0
Gallery at:
http://gallery.sohc4.net/main.php?g2_itemId=298318

Offline mj_honda

  • Enthusiast
  • **
  • Posts: 122
Re: Few quick Q's 72 CB350F edit: Need HELP ASAP (carb issue)
« Reply #6 on: May 15, 2008, 07:40:17 PM »
Let the O-Ring sit and dry for at least 2 days. More than likely it will shrink to normal. If not then it is time to take drastic measures.

Offline strangedaze39

  • Hot Shot
  • ***
  • Posts: 372
  • 1972 CB350F
Re: Few quick Q's 72 CB350F edit: Need HELP ASAP (carb issue)
« Reply #7 on: May 15, 2008, 07:41:25 PM »
Thanks guys, sorry for being suck a spaz  :P I got it fixed. I boiled it (didn't harm it at all) all the carb cleaner came out. I then actually threw it in the freezer (still strong as it was) and just kept working it into place. Eventually I got it good, and it wasn't cracked or anything.  ;D  I would not recommend doing that with a brittle gasket though it would probably not fair as well. Thanks for the help, btw I looked on ebay I search "clutch screw" and "clutch adjuster screw" nothing came up. If you don't mind could you post a link?

mj_honda I would have definitly let it sit but I couldn't unless I wanted to drain my whole gas tank right there in my garage. Since my float was being kept up by a wrench.

Thanks again,

SD
1972 Honda CB350F

Offline mattcb350f

  • Hardly a
  • Master
  • *****
  • Posts: 1,625
  • 1974 CB350F
1974 CB350F,  1980 CB125S,  1981 XL80S
Non Honda's: 86 & 87 Husqvarna 400wr's

My CB350F resto: http://forums.sohc4.net/index.php?topic=30467.0
Gallery at:
http://gallery.sohc4.net/main.php?g2_itemId=298318

Offline strangedaze39

  • Hot Shot
  • ***
  • Posts: 372
  • 1972 CB350F
Re: Few quick Q's 72 CB350F
« Reply #9 on: May 16, 2008, 10:04:02 AM »
Thanks Matt!! Both those will work perfect.
1972 Honda CB350F

Offline schneider419

  • Enthusiast
  • **
  • Posts: 104
Re: Few quick Q's 72 CB350F
« Reply #10 on: May 16, 2008, 02:02:42 PM »
as far as the gaskets go, i let them set for about a day. they shrink close to a usable size. or what i do now is i bought anorher set and swap them out every other time as i don't want to wait a day to put my carbs together again.