Topic: oil light comes on at idle

[jonda500]

Hi there, I looked this up before posting, but only found an unresolved thread where a cb750 owner had the same issue.
   The bike is a cb550. I have had an oil leak which seemed to be coming from around the oil pump. Yesterday I drained the oil, removed the oil pump and replaced the 2 oil pump o rings and the large pump body o ring and the oil gallery plug o ring (under the alternator cover) with genuine honda parts- I meticulously checked the part numbers and measured the new o rings everything checked out ok. I primed the oil pump, spilt oil every where trying to get the cog to line up, primed the oil pump again, second try it slid straight in. The oil pressure switch developed a fault where the oil light wouldn't come on after reinstalling the wire so after grounding the wire to check the oil light was working, I swapped out the oil pressure switch for a known good one. I replaced the engine oil with castrol 4T 20-50 the same as the engine had before.
   So today I'm sitting at a red light idling and the oil light came on - this has never happened before - it goes out when I rev it a little so I ride straight home, park, look down and the oil leak is just as bad as before....
   I'm thinking of trying a different oil pump/pressure switch combination(I have more new o rings) but I'm not sure it will make any difference. The surfaces where the o rings have to seal against look ok.
   Maybe the known good oil pressure switch I put in also decided to suddenly develope a fault? Any opinions would be appreciated, thanks  

[LesterPiglet]

Remove the casing covering the oil pump and try it. Sometimes the oil pump wiring grounds against this and can cause problems, it happened to me. If it changes you just need to re-orientate the oil pump switch wiring connection.

[ADW]

I recently re-read my 72 350F Owner's Manual and remembered something. On page 12, under the description of the Oil Pressure Warning Lamp, it states (after going through all the stuff about if it comes on while riding stop immediately, check the oil, etc. etc.):

"However, an occasional flickering of the warning lamp at or near idling speeds when the engine is at operating temperature, is of no concern since low oil pressure is normal at low speed."

So, if you know you have enough oil and it's only doing it a bit at idle, you may be just fine.

(PS: is your idle speed too low? A lot of people seem to like to have the bike idle speed quite a bit lower that specifications. Part of the reason for the idle speed being where Honda wants it is to help guarantee a proper oil flow volume and pressure.)

[dave500]

old oil pressure switches go faulty,try replacing it.

[Deltarider]

old oil pressure switches go faulty,try replacing it

+1

[LesterPiglet]

Well I replaced mine and then found I didn't have to when I found the grounding issue. Why not try the simple stuff before you spend money?

[calj737]

It seems like he has 2 problems: a "faulty" switch perhaps, AND an oil leak. He swapped switches and still gets a low idle light.

The switch problem sounds wiring/switch related.

Without a picture, can't say about the oil leak.

[martin99]

If the oil leak is that bad, then fixing it might cure the light coming on at idle issue too?

[jonda500]

The oil leak (as per picture) is about the same now, but definately not worse than it was before I tried to fix it. I just put my best oil pressure switch in (other pic) and I will report back whether this fixes the prob. (looking at the one I just removed it seems like oil has slightly seeped out from directly under where the wire connects)

ps thi smorning with the oil cold, I could make the oil light go out with 5 kicks (kill switch off so it didn't start), whereas yesterday with the oil hot, the oil light came on every time I allowed the bike to idle- the light was coming fully on, not dim or flickering! Wanting to avoid it even flickering, I had to maintain at least 2000 rpm.

[jonda500]

Phew, my oil light is back to normal (any time the engine is running at any speed the light is off!).
...and, I warmed up the engine with the cover off, noticed a drip on the frame rail beneath the oil pump and realised the oil pump outer cover is leaking. I will remove the three screws and fit a new 47mm o-ring under the cover next time I change the oil and filter- will I have to re-prime the oil pump after having the cover off?

[bryanj]

Check out other posts via the search engine, that outer cover ring is not in the 500 list but a Gold Wing one from somewhere else fits. i know the part numbers are on here 'cos I did it!!

[dave500]

you can if you want fill it through the oil sender hole.

[jonda500]

I think I will be inclined to see if can get oil pressure up without priming but I certainly wont start it unless I can get the oil light to turn off using the starter motor first though - I have no more pressure switches so I don't feel inclined to disturb the bloody thing while it's working as it seems to be a rather common time to fail when you have to disconnect and reconnect the wire! But that is an awsome tip to fill the pump through the oil sender hole thanks dave!
Bryanj, I thought the cover o-ring was the same as the oil pump to crankcase o-ring?- I can't  find a part number for it, but the description in the service manual(47mm o-ring) is the same as the description in my parts manual for the inner one which I have spares of.

[bryanj]

NO it's not the same mate, as i said use the search function for the goldwing part number and order it from Honda

91305-426-003   

[dave500]

ive used 46x2 orings for the oil pump cover just fine,go to your local bearing supply,if they have say a five dollar minimum purchase on small parts buy 30x3.5 orings in fours,they suit the inlet manifolds and the tappet cover caps,take one of your old pressure switches to supercheap auto or similar,compare it to whats on the racks,if it looks the same itll work,its an on/of switch set at about 7 psi or something?if you have zero oil pressure youll soon know,if your riding and get zero oil pressure you wont know till it locks up,unless you hook the switch to a beeper/buzzer?i had two 550 engines ex go karts,they had reverse operation oil pressure switches which were hooked to ignition,no oil pressure equalled engine shut off in that application,took me a few minutes to figure out why i couldnt get the lamp to work correctly?

[jonda500]

Awesome, thanks dave, great tip!- I took the cover off an old oil pump today (the screws were a b*tch to undo!) and realised I don't have any o-rings that size. I'll try the local bearing centre - in the past when I've tried to buy a small quantity of misc parts from them they just give them to me!
 Those oil alert cut outs are a #$%* if you don't know the engine has it but they seem like a better idea than just a light that lights up.

[alacrity]

Ingot I-rings for mine at theoringstore.com