Bike overheating & dying - Page 3 - Kawasaki KLR 650 Forum
2008+ KLR650 Wrenching & Mod Questions For repair, maintaining or modifying discussions related to the newly updated 2008 and beyond, Generation 2 KLR650 Motorcycle.

 4Likes
Reply
 
LinkBack Thread Tools Display Modes
post #21 of 57 Old 08-26-2019, 07:56 AM
1st Gear
 
Join Date: Jan 2019
Location: Long Island, NY
Posts: 61
Garage
How did the water pump look?

Please do not lecture me on the effects of temperature and density altitude on an internal combustion engine -Thank you.

2003 KLR650.... With all the bells and whistles
MTKKLR is offline  
Sponsored Links
Advertisement
 
post #22 of 57 Old 08-26-2019, 08:48 AM
5th Gear
 
Join Date: Jan 2011
Posts: 4,293
Heating issues aside, vacuum-actuated diaphragm can be tested:

Valve lever ON (or RES).
Disconnect fuel line at carb, place end in container.
Apply suction to vacuum port line (either run engine, or . . . you can figure it out! ).
Observe if fuel flows into container when vacuum applied to petcock through vacuum port hose.

If fuel flows under these conditions, chances are vacuum-actuated petcock is operational.

“You better put down that gun. You got two ways to go, put it down or use it. Even if you tie me, you’re gonna be dead.” "John Russell" (Paul Newman), Hombre
Damocles is online now  
post #23 of 57 Old 08-26-2019, 10:38 AM Thread Starter
1st Gear
 
ladytraute's Avatar
 
Join Date: Aug 2019
Location: Bay Area, Cali
Posts: 16
Quote:
Originally Posted by JdgDReDD View Post
Yes the fuel petcock is vacuum operated. If it starts leaking around the center post of the diaphragm it can cause symptoms like this. Basically the bike runs until the float bowl is empty then quits. Let it sit for a few minutes and it'll start and run until the float bowl is empty again.

the failing vacuum tap allows enough fuel to leak past filling the carb back up when it sits for a few minutes
I think you may have solved my problem! Read up a bit on here about converting to a manual petcock and the people who did seemed to have my same issue. I ordered the Eagle mike new part and will see how it goes. Thanks!
JdgDReDD likes this.
ladytraute is offline  
 
post #24 of 57 Old 08-26-2019, 10:38 AM Thread Starter
1st Gear
 
ladytraute's Avatar
 
Join Date: Aug 2019
Location: Bay Area, Cali
Posts: 16
Quote:
Originally Posted by Damocles View Post
Heating issues aside, vacuum-actuated diaphragm can be tested:

Valve lever ON (or RES).
Disconnect fuel line at carb, place end in container.
Apply suction to vacuum port line (either run engine, or . . . you can figure it out! <img src="http://www.klrforum.com/images/smilies/icon_smile.gif" border="0" alt="" title="Smile" class="inlineimg" />).
Observe if fuel flows into container when vacuum applied to petcock through vacuum port hose.

If fuel flows under these conditions, chances are vacuum-actuated petcock is operational.
Doesn't flow. /headdesk
ladytraute is offline  
post #25 of 57 Old 08-26-2019, 12:24 PM
OverDrive
 
Join Date: Nov 2009
Location: Lander, Wyoming
Posts: 5,466
Quote:
Originally Posted by JdgDReDD View Post
Yes the fuel petcock is vacuum operated. If it starts leaking around the center post of the diaphragm it can cause symptoms like this. Basically the bike runs until the float bowl is empty then quits. Let it sit for a few minutes and it'll start and run until the float bowl is empty again.

the failing vacuum tap allows enough fuel to leak past filling the carb back up when it sits for a few minutes
I disagree with your suggestion of how the vacuum operated fuel tap works. "Letting it set for an few minutes", does absolutely for or to the diaphragm. The spring Seats the o-ring and fuel flow Stops!

There can be NO Fuel flow thru the fuel tap to re-fill the float bowl with a dead engine. The vacuum operation Must be operable to Re-Fill an empty float bowl with-in about 20 seconds of cranking the starter motor, with zero 'choke' and closed throttle.

If the petcock vacuum diaphragm can work during cranking it will always work during normal running.

If both layers of the diaphragm were rotted thru and the Air Vent groove/WEEP HOLE in the plastic divider was somehow plugged with crud, the engine would be sucking extra gas thru the small vacuum hose and directly into the engine. It would flood so badly, so quickly that one wouldn't even make it around the block. IMHO.

pdwestman
Modify at "YOUR OWN RISK"!

Still riding my 1987 KL650-A1. 85,000+ miles & counting
pdwestman is offline  
post #26 of 57 Old 08-26-2019, 12:35 PM
OverDrive
 
Join Date: Nov 2009
Location: Lander, Wyoming
Posts: 5,466
Quote:
Originally Posted by ladytraute View Post
Doesn't flow. /headdesk
An empty Visine bottle can apply enough vacuum to the vacuum hose disconnected from the carburetor to open an operable fuel tap diaphragm.

I've filled an empty, sort of clean soda bottle with gas from my KLR along the road side to get the wifes KZ550 to the next town, with my lips. Had to of looked like I was kissing my KLR to the highway traffic, haha.

pdwestman
Modify at "YOUR OWN RISK"!

Still riding my 1987 KL650-A1. 85,000+ miles & counting
pdwestman is offline  
post #27 of 57 Old 08-26-2019, 01:23 PM
1st Gear
 
Join Date: May 2019
Location: Lake Macquarie, NSW, Australia
Posts: 36
Reading all this things me that twice over the years I have had tap diaphragms fail twice such that extra fuel was sucked down the vacumn line and flow down the main fuel line became erratic. In both cases it have me very rough running at idle but did not stop the engine at higher speeds, so I agree with JD that this could be the explanation.

For the overheating I would be checking the thermostat - they don't fail often but when they do they often stick partially open which may explain the rapid temperature rise when stuck at lights and stop signs, but quick recovery on the open road.

Good luck

Sent from my Moto G (5S) Plus using Tapatalk
awayonmybike is online now  
post #28 of 57 Old 08-26-2019, 01:25 PM
1st Gear
 
Join Date: May 2019
Location: Lake Macquarie, NSW, Australia
Posts: 36
Oops sorry, for the garbled the first sentence above. I forgot to proof read.

Sent from my Moto G (5S) Plus using Tapatalk
awayonmybike is online now  
post #29 of 57 Old 08-26-2019, 02:55 PM
OverDrive
 
Join Date: Nov 2009
Location: Lander, Wyoming
Posts: 5,466
For fuel to be sucked down the vacuum hose to the carburetor, both diaphragms have to have failed & the atmospheric air vent/weep hole in the gray plastic separator disc would probably have to be plugged, otherwise wouldn't fuel leak externally thru the air vent/weep hole?

If both of the diaphragms are GOOD and the air vent/weep hole is plugged, could it be that the diaphragms retract enough with lowered vacuum of partly open throttle to restrict fuel flow such that the float bowl does suck dry? With the higher vacuum applied at cranking speeds with a closed throttle plate & at very low throttle openings the float bowl might re-fill/stay filled? In this scenario, a simple disassembly and cleaning of the diaphragm assembly may be all that is required.
But this still does not address the possible temperature issue.

pdwestman
Modify at "YOUR OWN RISK"!

Still riding my 1987 KL650-A1. 85,000+ miles & counting
pdwestman is offline  
post #30 of 57 Old 08-26-2019, 04:11 PM
4th Gear
 
GoMotor's Avatar
 
Join Date: May 2014
Location: Texas
Posts: 1,233
Quote:
Originally Posted by ladytraute View Post
Doesn't flow. /headdesk
If the petcock "Doesn't flow" with vacuum applied to the vacuum line, I wonder how the engine runs long enough to push the temperature gauge up to the red line.

I was going to suggest removing the spring in the petcock so gas can flow freely through the petcock and plugging the vacuum line and the vacuum tap on the petcock. This should allow gas to flow freely through the petcock in the "On" position and not flow in the "Off" position just like a non-vacuum petcock for testing purposes, but without the cost.

I like the vacuum petcock because, if I can forget where I left my keys, I can forget to turn the petcock off.
Tom Schmitz and pdwestman like this.
GoMotor is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Kawasaki KLR 650 Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may 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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome