ADVrider

Go Back   ADVrider > Bikes > Thumpers
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 07-05-2010, 01:22 PM   #1
Kaanan OP
Knee deep in snow.
 
Kaanan's Avatar
 
Joined: Feb 2008
Location: De Pere, WI
Oddometer: 591
Plunger Starter on a CVK40

Hey guys,

I have recently been bitten by the broken choke (plastic fitting on the carb) bug. I decided it was not worth it to buy another plastic one, so I got the plunger type i've seen others use.



I was taking the carb off in the first place to take one washer out, as I did the .22 cent mod and the bike was running crappy in the mid range. Long story short, with the new choke on the bike will not start. I've adjusted the idle screw, the mixture screw (the one on the under side of the carb) and I just can't get it to fire up. I know this mod has been done before, and harley actually uses one very similar on their sportsters. Any help on what I can do to get her running would be awesome.
Kaanan is offline   Reply With Quote
Old 07-05-2010, 01:23 PM   #2
Kaanan OP
Knee deep in snow.
 
Kaanan's Avatar
 
Joined: Feb 2008
Location: De Pere, WI
Oddometer: 591
This is similar to the plunger starter I bought.

Kaanan is offline   Reply With Quote
Old 07-05-2010, 01:26 PM   #3
Kaanan OP
Knee deep in snow.
 
Kaanan's Avatar
 
Joined: Feb 2008
Location: De Pere, WI
Oddometer: 591
I am working on her again. I figured out it can make her run for a short while (about 10 seconds) with full choke and about 80% throttle. But when the throttle is increased or decreased, she just dies. Same happens if I take the choke off. Also, the exhaust is almost white, very thick and gassy smelling.

So then I was in the process of taking the carb off, and gas started pouring out of where the carb is attached to the boots. It seems to be flooding. It even seems like a little bit of gas is coming out of where the new choke is attached.

When I realized how much gas must be getting into the engine, causing it not to run, I drained the float bowl. Then I started it up on full choke with no throttle, and it would run for a few seconds and die again. Gas would again pour out if I took the carb off.

Does this sound like something could be clogged? I am diving into my carb right now, and would love and bit of guidance andbody could give me.

Below are pictures of the differences between the two chokes.

This is where the choke operates.


Here the choke is fully closed.


Here it is open partially.


Here is the old choke.


You will notice the old choke has a guide pin. That is the only real difference, but could it be whats causing me all of these problems?
Kaanan is offline   Reply With Quote
Old 07-05-2010, 01:36 PM   #4
XDragRacer
Beastly Adventurer
 
Joined: Mar 2009
Oddometer: 2,973
Excess gasoline suggests faulty float valve/float valve seat.

Symptoms regarding reluctance to run suggest to me possible diaphragm air leak.

If the "choke" (starting enricher) plunger [assuming correct part] seats fully, and retracts fully, doubt that component is the source of your trouble.

XDragRacer screwed with this post 07-05-2010 at 09:03 PM
XDragRacer is offline   Reply With Quote
Old 07-05-2010, 06:37 PM   #5
subybaja
Beastly Adventurer
 
subybaja's Avatar
 
Joined: Jul 2007
Location: Anchorage (Spenard)
Oddometer: 2,889
Quote:
I decided it was not worth it to buy another plastic one,
Howzabout an aluminium one?

http://www.steadengineering.com/product.sc?productId=2
__________________
We had part of a Slinky. But I straightened it.
subybaja is offline   Reply With Quote
Old 07-05-2010, 07:29 PM   #6
JeffD
Gnarly Adventurer
 
JeffD's Avatar
 
Joined: Nov 2002
Location: missoula,mt
Oddometer: 487
I think the guide pin is what blocks off the fuel flow. So if you don't have that on your new one it is probably dumping fuel in at a high rate.
JeffD is offline   Reply With Quote
Old 07-05-2010, 07:48 PM   #7
guns_equal_freedom
Beastly Adventurer
 
Joined: Jul 2007
Oddometer: 5,484
Quote:
Originally Posted by JeffD
I think the guide pin is what blocks off the fuel flow. So if you don't have that on your new one it is probably dumping fuel in at a high rate.
No.
I have an 06 KLR650, I replaced the KLR choke lever / cable / plunger with a plunger assembly from an 06 KX250F.

The KX250F does not have the guide pin.

It works just fine on my bike.
guns_equal_freedom is offline   Reply With Quote
Old 07-05-2010, 07:50 PM   #8
XDragRacer
Beastly Adventurer
 
Joined: Mar 2009
Oddometer: 2,973
Quote:
Originally Posted by Kaanan
You will notice the old choke has a guide pin. That is the only real difference, but could it be whats causing me all of these problems?
Yes, as JeffD posts above, the "guide pin" enters the enrichment fuel orifice in the carburetor and seals it when the "choke" (starting enricher) is OFF. When the "choke" is ON, the "guide pin" is withdrawn from the fuel orifice, permitting fuel to flow and enrich the combustion mixture. My perceptions only; I could be in error.

Without a "guide pin," appears to me fuel would flow continuously into the carburetor whether the "choke" was ON or OFF.

This link might be helpful:

http://www.gadgetjq.com/keihin_carb.htm

XDragRacer screwed with this post 07-06-2010 at 08:01 AM
XDragRacer is offline   Reply With Quote
Old 07-05-2010, 09:28 PM   #9
JeffD
Gnarly Adventurer
 
JeffD's Avatar
 
Joined: Nov 2002
Location: missoula,mt
Oddometer: 487
try swapping the plunger.
JeffD is offline   Reply With Quote
Old 07-06-2010, 05:01 AM   #10
Kaanan OP
Knee deep in snow.
 
Kaanan's Avatar
 
Joined: Feb 2008
Location: De Pere, WI
Oddometer: 591
Quote:
Originally Posted by JeffD
try swapping the plunger.
Swapping the plunger for what? The little plastic piece holding the choke onto the carb is destroyed. The only way to get a new plunger starter is to order another, which took the last one ten days to get here.
Kaanan is offline   Reply With Quote
Old 07-06-2010, 07:53 AM   #11
XDragRacer
Beastly Adventurer
 
Joined: Mar 2009
Oddometer: 2,973
Quote:
Originally Posted by Kaanan
Swapping the plunger for what?
I think JeffD meant re-use your old plunger with your new "choke," if that's practicable.

From the link above,
Quote:
This system is referred to as the
choke. But that's a misnomer. When
you apply the choke lever, what
you're doing is retracting a plunger
that opens a tube connected to the
starter jet, allowing additional fuel
to enter the venturi just below the
vacuum hose nipple. It supplements
the pilot system at start up.
Accompanying pictures from the link show the relationship described. Not mentioned, but when the choke is ON, a corresponding air passage opens also (shown by arrows descending in the diagram).

Looks to me like the "guide pin" seals the fuel orifice when the choke is OFF; clarifications and corrections welcomed.

XDragRacer screwed with this post 07-06-2010 at 07:59 AM
XDragRacer is offline   Reply With Quote
Old 07-06-2010, 10:00 AM   #12
JeffD
Gnarly Adventurer
 
JeffD's Avatar
 
Joined: Nov 2002
Location: missoula,mt
Oddometer: 487
what xdragracer said. the plunger with the guide pin should be able to hook onto your new cable. I have swapped them back and forth on stock cables so maybe your new shorter cable is different but if they are like normal cables you can. The plunger (starter valve part #27583-88 harely part #) is availble at any harley shop. Maybe try a harley store and see what they have in stock for the enricher cable.
JeffD is offline   Reply With Quote
Old 12-07-2014, 09:02 AM   #13
phyclecis
n00b
 
Joined: Sep 2014
Location: northern New Jersey
Oddometer: 3
How bad is your plastic cap/nut broken? On mine just a v shaped piece broke off from the pressure of the bend pipe that fits in it, just about one third arround and half way down the hex part of it or so, I put a dab of super glue on it just to keep it together and while all together on the. Pipe with cable and plunger on so as not to let it cave in from the pressure I slipped a shrink tube sleeve on it, shrank it n for good meassure slipped a shorter piece on top of the first and shrunk that one in place too, put it back and its been holding up so far.
Thinking of ordering one of those metal ones to keep arround in case this one fails but so far it. Is working fine and hopefully don't have to mess with it for some time
phyclecis is offline   Reply With Quote
Old 12-07-2014, 09:37 AM   #14
phyclecis
n00b
 
Joined: Sep 2014
Location: northern New Jersey
Oddometer: 3
I would take the carb off again and go over it one more time. You may have overlooked something simple but crucial, like the needle guide that often slips out unnoticed or was put back in backwards double check the float and inlet needle valve, some times a little bit of dirt gets stuck in there and it won't seat right, also make sure that the vaccumme hole in the slide did not get covered by one of the legs on the plastic spider thing. That goes over the jet needle this will make the slide not actuate when you throttle up and chocke the bike shutting it off, and offcouse check the diaphragm for cracks pin holes and that it sit in the groove without pinches ( I usually spread a little lithium grease film in a few spots arround the groove to hold it in place) you may find something you missed and be back on the saddle in no time with little more than some time spent! Cheers!
phyclecis is offline   Reply With Quote
Old 12-07-2014, 11:41 AM   #15
EmBeeZedEx
Adventurer
 
Joined: Jul 2014
Location: Seatown, PNWet
Oddometer: 91
float is stuck open. no bones about it. Either the float itself is hung up or the viton needle has some junk caught in it or the float height setting is out of whack.

Vaguely possible the hing pin has wandered off, out of one of the holes in the posts.

If the whole carb is swimming in gas whenever the petcock is open then that has nothing to do with the enrichener plunger.

Try the whole operation again, empty the bowl, pull the "choke" open and while you crank the starter, rap on the bowl with a plastic screw driver handle.
Floats sometimes get hung up on the bowl walls. Also might knock a bit of sediment off the viton needle. A little piece of something that was in the bowl before ya swished it around.

Stay confident, stay cautious. Carbs thwart everyone most of the time.
EmBeeZedEx is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


Times are GMT -7.   It's 09:10 AM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014