1978 GL1000 Oil Light comes on intermittently

[77Gowing]

Best of luck with your results.

[CYBORG]

I think the clutch material guys may have had it right all along. I was reading about clogged scavenger pumps on Wingovations and the material clogging the pump looks like a compressed version of what I found in my oil pan. Maybe some deposits got knocked loose. I'm going to fix the rodent damage, install a mechanical oil pressure guage in place of the fuel guage, and just keep an eye on things and see if the contamination lessens. Thanks.

I think your symptoms are sorta normal. And not really a problem as long as the screen is not clogged. If that happens you will lose oil pressure

[low-side]

So I put a nice oil pressure guage on in place of the non-working fuel level guage. Shows over 65 psi at high idle cold. When fully up to temp at idle it shows 0, but quickly climbs into the 20s by 2000 rpm and reads in the high 30s cruising at 5000 rpm. Heavy acceleration from any engine speed will bump it up into the 60s and then it comes down to normal very quickly after easing off the throttle. It still runs well, so I think this is pretty normal. Anyone else running a guage getting different results?

[desertrefugee]

Sounds like a good reason to keep on riding it - but pretend you're a Harley guy during extended idling. Blip the throttle every few seconds. You'll keep oil in the bearing surfaces - and you'll sound cool.

[Whiskerfish]

zero at idle would not be acceptable to me in any way and verifies you caution light. Normally when i drain my oil for a change after she is full again I hit the kill switch and crank it over till the pump gets primed and the light goes out before allowing it to fire. Usually takes about 30 seconds.
Me I would tear that pump out and replace or rebuild it

[desertrefugee]

Most gauges are rotten at measuring anything accurately below about 5 psi. I’d get a second opinion, I.E.a different gauge.

[robin1731]

Specs call for;
cranking; cold-18 hot-5
900rpm; cold-60 hot-12
5000rpm; cold-64 hot-60


I wouldn't ride it until I found out why yours is so low.

.

[CYBORG]

Factors like the type oil you are using, idle speed. etc can effect oil pressure. Light comes on at about 2 psi. if to factory spec. idle should be around 1000 rpm to 1100 rpm. I also run gauges, and never see below 20psi on my 1000 at idle. If everything else is correct, I would be concerned bout my pump

[low-side]

Next time I have it up to temp enough that it's hitting those really low numbers I will use another guage I have to compare readings between the two. I think that the 0 reading at idle is likely the guage unable to display low readings, as Desert Refugee mentioned earlier. This is the electric oil pressure guage I'm using: http://prosportgauges.com/Clear-lens-52 ... gauge.aspx. I suppose it's a good thing I have two spare low-mileage engines.

[low-side]

Well, I got wet on the ride but I got the bike up to temp and swapped my sender out and my mechanical guage in in under a minute. Mechanical reads 12 psi hot at 1000 rpm idle and 67 psi at 5000 rpm. Given that she runs fine and my last oil change was clear, along with these results, I'm going to conclude that my oil pressure is fine and contact Prosport about the sender. Octane, in case I can't get anywhere with Prosport, what is your guage setup? Thanks to everyone for your comments - I really appreciate them.

[robin1731]

Well, I got wet on the ride but I got the bike up to temp and swapped my sender out and my mechanical guage in in under a minute. Mechanical reads 12 psi hot at 1000 rpm idle and 67 psi at 5000 rpm. Given that she runs fine and my last oil change was clear, along with these results, I'm going to conclude that my oil pressure is fine and contact Prosport about the sender. Octane, in case I can't get anywhere with Prosport, what is your guage setup? Thanks to everyone for your comments - I really appreciate them.

Octane?

.

[low-side]

Thanks for catching that Robin. Another topic, another board. Sorry Cyborg. What is your oil pressure gauge setup?

[desertrefugee]

Octane, Cyborg, Robin. What's the difference? Essentially just different manifestations of the same persona.

[CYBORG]

Thanks for catching that Robin. Another topic, another board. Sorry Cyborg. What is your oil pressure gauge setup?

I use a Quality 2 and a half inch with 50psi at 12 o'clock. And I always use copper line to feed it instead of the nylon. Tapping in where the normal sending unit does. I forget the name of them, but can go look if you need it. I like the larger gauges because the distance between numbers is easier to see. That's on my 78. However on my 84 I use smaller ones, simple because of the space available. I also monitor oil temp.

[low-side]

Please don't make a special trip, but when you get a chance the brand name of the guage would be great. I thought I had a good one with this, but it seems to read about 10 - 20 psi low. Thanks.