red light

[greeezer]

This is my second time to post here but I read this forum religiously. So now I need advice again for my '79 1100 Special. The problem is my red oil light is coming on and I'm not sure why. I did a search and got a lot of good info,, almost too much info. Is the light an oil level light and not an oil presure light? It seems some guys were talking about just disconnecting the light and going on and some were talking about a reset button. My oil level glass shows full. What gives?

[Dragon Tamer]

Greezer,
This seems to be a common problem with the beasts, it could be as simple as a bad pressure sender (on a special it is pressure) or it could be a bad spot in the wiring gounding out somewhere. I have had several sessions withe the Dragon over this and have had to change out the sender on one occasion and repair the wiring on two others. The thing I watch is this, put the bike on the center stand and start the engine, watch the oil level, if it goes way down with the engine running then the oil pump is working and you have oil pressure (at least to some amount). In this case you either probably have a bad sender or bad wiring, if the oil level does not drop you have some other oil related problem and it should be addressed immediatly!
One of these days I am going to put a mechanical gauge on her and answer all the questions and quit worrying about the damn idiot light!

[mro]

One of these days I am going to put a mechanical gauge on her and answer all the questions and quit worrying about the damn idiot light!

If uncertain after checking the wiring and pressure switch that would be the next thing I'd do.

Oil pressure switch is a "normally closed" switch, so if there is a bare spot on it's wire anywhere touching metal (grounding it) light will come on. Possible for switch to go bad but so far no problem with any of my XSes.


mro

[oseaghdha]

Re: red light

Originally posted by greeezer
This is my second time to post here but I read this forum religiously. So now I need advice again for my '79 1100 Special. The problem is my red oil light is coming on and I'm not sure why. I did a search and got a lot of good info,, almost too much info. Is the light an oil level light and not an oil presure light? It seems some guys were talking about just disconnecting the light and going on and some were talking about a reset button. My oil level glass shows full. What gives?

The oil light is also the brake/tail light warning.
Check the plugs and wires/socket to the tail light.

[Jerry]

The XJ series uses an oil level indicator where as the XS uses an oil pressure sensor. The XJ has a Reset button in the gauge cluster that can reset the sensor if there is an error in the circuit. The XS does not have this button.

On the XJ, a 'false' reading is fairly common; my guess is that the oil level sensor gets gummy after many years of operation and hangs up occasionally. The sensor is in the oil pan. On the XS, the pressure sensor is below the carbs and slightly right of engine center; is fairly easy to spot.

I did have a problem with a Yamaha oil pressure sensor on another bike; oil had gotten on top of the sensor and was shorting the 2 connectors, giving a false reading. Cleaned the top of the sensor and all was fine.

As noted previously, problem can also be in a lighting circuit. This is more probable. so check your bulbs and wiring.

[Spide4x4]

I had the same thing happen and upon troubleshooting, it was because the oil filter was a bit dirty.

[greeezer]

red light

Thanks for all the good advice. I checked the oil senser on top of the engine, the wiring and finally the oil level in the sight glass. My oil level was close to the low mark so I added oil,duh! Anyway, I must have done sonething right because so far no red light any more. Again, thanks for all the input.

[TADracer]

Same has happened on my 79 special. Unless you hear some drastic engine noise or see a puddle of oil on the ground before you ride, I would figure the oil pump is working fine and the wireing/sender is suspect. I disconnected the wireing plug at the sender and in the headlight and put a dab of dielectric grease on the connections and pluged it all back in. Has not happened since.

[Dragon Tamer]

As I have stated before the warning light on the Dragon tends to come on at times. Sometimes it comes on for just a couple of seconds and sometimes it stays on for three to five minutes, then it goes back off. The only thing that was certain was that at any given day it would come on somewhere along the line.
I had ordered a mechanical gauge for the old girl but the adaptor that came with it was not even close to what is needed to hook it to the engine and I have not yet found one that will work. May be a moot point now as I have discovered something else.
Last week while preparing for a ride I got her up on the stand and changed the oil and filter, checked the brake pads and turn signals etc. While checking the lights I noticed that the rear brake/tail light lens was a little dusty on the inside and pulled it off to clean it. While I had the lens off to clean it I decided to change the bulb as I happened to have a new one right there on the bench and I didn't know how long the old one had been in there.
To make a long story shorter, we went on to put over 600 miles on last weekend and I have been riding the bike to work all this week and that irritating SOB of a red light has not come on ONCE when it should not have. I have not checked it, because I pitched the old light in the trash, but I am thinking that the resistance on the tail light filament may have been rising and the sensor was reading that as a failed bulb! Conversly it could have been a poor connection in the socket but it is absolutely clean and I don't consider that likely.
So if you are having troubles with the red light, try a new tail light bulb, it just may work for you also!

[planedick]

Oil pressure guage

I manufacture a stainless fitting to allow you to put an oil pressure guage on your bike. It fits just beneath the carbs on the left side and is easily viewed as you ride. I don't have a pic yet, but if you're interested, I'll take one and give you pricing.

[planedick]

Pic

Here's a pic of my oil pressure guage

[HobbyMan]

If it is not oil, it is probably the brake light. Check to see if your tail light is on when the light comes on. Chances are that is what it is. Therer is a "light checker unit" or something like that. On my 79SF the light kept cooming on randomly untill I cleaned the light checker unit connections. I think it is around the battery on the left side of the bike. THe PO may have moved mine to a different location.

[mro]

Here's a pic of my oil pressure guage

Looks pretty.
Any way to route it to near the gauges on the handle bar?

mro

[pggg]

Here's a common auto type pressure gauge rigged

[planedick]

Near guage cluster

If you want an oil pressure guage near the others, Electronic is the way to go. A tee at the present one and a sending unit there so you can put the guage whereever you want.