Honda CX 500 Forum banner
1 - 20 of 31 Posts

·
Registered
Joined
·
7,767 Posts
Discussion Starter · #1 ·
So back to the kid's bike with an untested engine. All was fine for a few days, went to start it up and could not get the oil pressure light to turn off.

Plenty of fresh oil/filter and washer/spring in place
Wire from sensor to harness checks ok
All fuses Ohm'd out good
Did not spend a lot of time on oil pump during recondition but seemed to work ok for a few days?

Do the oil sending units go bad and is there a way to test. I know nothing about these units operation!

Any thoughts welcome. thanks
 

·
Registered
Joined
·
7,767 Posts
Discussion Starter · #2 ·
Just found a testing procedure with MM and air on a unit I have out of old engine. Normally closed. add air and it opens. Good test as far as I know.

Tried on bike with existing unit. normally closed, cranking engine still closed. guess this does not rule out the pump?

Going to pull old unit and try the one from the old engine.
 

·
Registered
1978 CX500 "The Grub", 1983 GL650I "Nimbus"
Joined
·
12,075 Posts
If you remove a valve cover, you can visually verify oil flow.
 
  • Like
Reactions: nolimitz

·
Super Moderator
Joined
·
23,713 Posts
Switch is NO type. It closes with pressure. Can also be tested with a syringe full of oil and a continuity measurement between terminal and body. Switching occurs at only about 5 PSI.
 

·
Super Moderator
'84 CX650E that is evolving into a GL500
Joined
·
18,408 Posts
Um... The switch completes the circuit between the light and ground. The light is on when there is no oil pressure and turns off when there is pressure so it must be a Normally Closed type (opens with pressure to turn the light off).

BTW: I'd swap in the known good one from the old engine too.
 

·
Registered
Joined
·
7,767 Posts
Discussion Starter · #7 ·
Um... The switch completes the circuit between the light and ground. The light is on when there is no oil pressure and turns off when there is pressure so it must be a Normally Closed type (opens with pressure to turn the light off).

BTW: I'd swap in the known good one from the old engine too.
Agree here Bob.
Pulled the left valve cover and fired it up. she is pushing oil to the top of engine. Kid had other stuff to do today, Im finishing taxes and guardianship stuff for my daughter so I hope to get back to it tomorrow. Did I ever say I hate April deadlines?
 

·
Super Moderator
'84 CX650E that is evolving into a GL500
Joined
·
18,408 Posts
I know what you mean. Years ago I used to change from the winter sidecar outfit to the summer 2 wheeler in mid April and back to 3 wheels in mid October but I've drifted away from that over the last decade or so. I moved the summer bike to the garage last week and most of its pre season maintenance is done so I was starting to think I'd have it on the road on my old schedule this year.
Then I looked at the forecast and saw a couple of inches of s**w (censored for those who don't want to see that word this time of year) predicted over the weekend and decided I'll be happy if I change over before the end of the month.

I looked at your forecast and it is a bit better than ours (not a lot). We should both be glad we don't live in Winnipeg where they are expecting a foot of it in the next 3 days.
 

·
Super Moderator
'84 CX650E that is evolving into a GL500
Joined
·
18,408 Posts
I don't have much sympathy for ski resorts that get snowed on. They spend too much time asking for it. Literally. ;-)

It was actually not bad out here today except for a bit of rain.
 

·
Registered
Joined
·
7,767 Posts
Discussion Starter · #14 ·

·
Registered
Joined
·
1,531 Posts
Well, the oil pressure switch swap had no effect. guess I'll be tearing into the oil pump tomorrow.
bummer
That is a bummer. I know you know these bikes well but just a reminder, check that the oil orifice Is in place and facing the right direction. You might also want to inspect the oil and filter for gold or copper colored specks. I hope it’s an easy fix.
 

·
Registered
Joined
·
7,767 Posts
Discussion Starter · #16 ·
That is a bummer. I know you know these bikes well but just a reminder, check that the oil orifice Is in place and facing the right direction. You might also want to inspect the oil and filter for gold or copper colored specks. I hope it’s an easy fix.
Will do all of the above. I've been wondering about the orifice?Thinking I may swap the oil pumps as well if need be
 
1 - 20 of 31 Posts
Top