XJ6 fuel tank changeover switch
#1
![Default](/forum/images/icons/icon1.gif)
Love my 1986 XJ6 - BUT - on the drive home after purchasing, the fuel gauge quit working. The fuel tank switch doesn't work either - no fuel gauge readings and the actual changeover valve doesn't perform its function. Should I be digging into switch testing and diagnostics or is this a common issue usually solved by ????? Any help would be appreciated.
#2
#3
Join Date: Mar 2014
Location: Tehama County, California, USA
Posts: 25,579
Received 9,383 Likes
on
5,441 Posts
#5
#6
Join Date: Aug 2018
Location: Phoenix Arizona - Mountain Park Ranch
Posts: 90
Likes: 0
Received 49 Likes
on
30 Posts
![Default](/forum/images/icons/icon1.gif)
My XJ6 had sat unused for the last several years and the switchover function didn't work correctly. Exercising the switch on the dash didn't seem to do anything and the fuel always read the same for both tanks.
If I filled one tank and not the other, they would eventually equalize to half a tank in each.
It seemed to me that the most likely failure mode was a gummed up switchover valve in the boot from having sat unused for long periods of time.
Waited until the tanks were mostly empty and then removed the switchover valve in the boot. I took a plastic rod and exercised the plunger - it was sticky. I squirted some WD40 into the ports and exercised the plunger manually maybe 50X or so until it shuttled freely in the housing. Checked continuity in the coil too while I had it out.
I reinstalled the switchover valve and everything worked fine. Took about a half hour.
Had it not worked, the next step was to go through the electrical diagnostic that Doug D wrote and posted in Yellow Series3's message.
If I filled one tank and not the other, they would eventually equalize to half a tank in each.
It seemed to me that the most likely failure mode was a gummed up switchover valve in the boot from having sat unused for long periods of time.
Waited until the tanks were mostly empty and then removed the switchover valve in the boot. I took a plastic rod and exercised the plunger - it was sticky. I squirted some WD40 into the ports and exercised the plunger manually maybe 50X or so until it shuttled freely in the housing. Checked continuity in the coil too while I had it out.
I reinstalled the switchover valve and everything worked fine. Took about a half hour.
Had it not worked, the next step was to go through the electrical diagnostic that Doug D wrote and posted in Yellow Series3's message.
The following users liked this post:
Doug (05-17-2019)
#7
Thread
Thread Starter
Forum
Replies
Last Post
ahunt4
XJ6 & XJ12 Series I, II & III
2
01-22-2015 08:27 PM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)