Triumphrat

winter of 69 · 02-26-2010, 06:19 PM

Hi, Im new on here.

I'm happy with my bike. though the bike seems to prefer giving it full instaed of part throttle.
I recently did the 16000 service and have since started it up it runs fine and left it at idle for ages to check for leaks.

After getting up to temp the oil light came on!

If revved it goes out. I have since put an oil gauge next to the oil switch. It has 5 bar pressure when revved but drops off to 1 bar or less when hot at idle.

The engine sounds fine and according to the dealer they rev uneven at idle which may cause this!

Does anyone know what pressure the switch activates the light on the dash! The dealer didnt know!

BombFactory · 02-27-2010, 02:20 PM

I don't know at what pressure the switch is activated at, but the pressure should never be dropping lower than 2 bars (30 psi) when hot. These are close tolerance engines, and they put out 4.6 bars (67 psi) at 6,000 rpm hot. I'm not sure what the person you spoke to is trying to say about fluctuating idle speed causing issues, as the engine should not be fluctuating in idle speed more than 200 rpm, and the proper idle speed of 1,000-1,300 is designed to keep the oil pressure at a proper level that does not trip the low oil pressure switch.

I'd say it may be the switch, but because you have a gauge that is showing 1 bar at idle (a meager 15 psi!!), I think you have a problem with the pump. Theoretically speaking, an engine can idle on very little oil pressure (even 5 psi), so long as there is a complete layer of oil to float the moving parts off of each other. However, an engine idling with 1 bar of pressure is not going to last as long as one with 2+ bars.

winter of 69 · 02-27-2010, 05:03 PM

Thanks for the advice

Like ive said it makes at 6000 revs the required pressure 4.5 to 5 bar! When cold it is fine at idle. I wonder if i change to 15/50 oil will help as its on 10/40 at the mo.

If the pump was out of tolerance surely this would effect pressure all through the revs.

Whichever way it may not be the switch!

It was idling very low when i bought couple of months back. I ve since tried increasing idle speed to 1200rpm.

Would you recommend those oil pressure additives 'SDP' or slick 50 type products to increase pressure.

BombFactory · 02-27-2010, 08:30 PM

Trying to change oil viscosity or adding additives is counterproductive, as the oil pressure should always be within spec when running 10W40 or 15W50. Although you are getting the proper 4.5 bars at 6K rpm, the pump could still be having issues producing the pressure at idle. 6k rpm may be enough to move the oil, while 1,200 rpm may not.

If you are sure your mechanical gauge is reading properly, I would seriously consider looking into the pump. In my opinion, the time and money to deal with the pump is a much safer bet than to keep running it just to have the pump go out 600 miles from your house, possibly destroying the bearings.

winter of 69 · 03-02-2010, 04:20 PM

After much worrying, headscratchin, tea, aswell speaking to several people at triumph aswell as your comments bombfactory, it seems the problem may be sorted... touch wood (hairs thinning fast)

The concensous if its making 4.5 + pressure at 6000rpm then it'l be fine. Also the pipe that feeds the switch to the rocker cover can get an air lock.

The gauge was replaced with a lower pressure one to monitor the pressure, and the switch renewed

BombFactory · 03-02-2010, 08:17 PM

I don't enjoy beating a dead horse, but I don't see much logic in the thinking that the oil pressure doesn't need to be always within factory spec, thus triggering the light when not, just as long as it reaches spec by 6,000rpm. The reason for this is that the bearings and other components are not getting their designed protection at idle, nor are they getting their designed and necessary protection at the critical moment when the engine is increasing in speed from idle up to 6K rpm. This is a pivital moment when components need all the protection they can get.

I've never heard of anyone having an airlock issue with the oiling system, which isn't to say it hasn't ever happened, nor have I heard of someone having persistent low oil pressure without having a negative cause and effect. It just doesn't seem logical to me to say, yes, there is a problem somewhere (be it oil pump, airlock, or gauge), and no, I'm not going to find and repair it.

However, all I can do is give my opinion and experience, as it is ultimately your money and life.

winter of 69 · 03-04-2010, 06:21 PM

The comments about the 'air lock in the cam cover oil pipe were the local dealers.
The advice about the oil pressure at 4.5 bar at 6000rpm and dont worry too much about the idle pressure was the triumph factory technicians... not mine. They did state though the switch was more than likely the problem.

It seems to be the old switch triggered to soon, causing the misread.

The bike runs fine, did before and since the switch was renewed still does the oil light NO longer being illuminated.

So can only assume it was the switch all along not any pressure issues.. Therefore the bikes tickover with 1 bar of pressure.

I was glad to receive any helpful hints/tips advice but

Im sorry you dont want to believe my engine is fine and dandy, or is it due to you not wanting to be proved wrong..

you dont need to flog the horse any longer

PS to acheive the correct oil pressure the correct tolerances within the bearings and galleries the differential between flow and pressure is determined by those factors above and not just how much pressure a pump can give pump i.e. a pump pumping oil into a sump wont achieve any pressure at all..