I thought I'd go out for a blat round my local 20 mile 'circuit' on friday evening. Imagine my suprise when I got home to find a trail
of oil behind be and a pool forming under the engine!! After about 30 mins inspection I found that the T piece I had put into the oil pressure switch
tapping had sheared most of the way through and was held on by about 1/3 of a thread.........not good. I was using a T so that I had an oil pressure
switch and a pressure sender, but the pressure sender was faulty and the hole was blanked off at the time. I can only summise that the offset load of
the oil pressure sender (telemetrix type) on the T was too much for the 1/8 BSP thread and it let go (even though the sender wasn't fitted at the
time!) So anyone who has a similar setup beware. I still haven't dared starting it although the low oil pressure light didn't come on and
there is a tiny bit of oil on the dipstick when it is screwed in.
Ben
I hope it's all ok.
I was advised by Digidash to fit the oil pressure sender (due to it's size and weight) onto the chassis and use a piece of high pressure braided
hose to connect it to the block. So no vibration/breakage problems.
I think oil pressure senders off to the bin and I'll live with just the switch as on the bike!
Ben
I would just use a pressure gauge if I were you, preferably one with a tell-tale warning light that you can set to a reasonable pressure. The standard
pressure light is pretty much useless as it often comes in at such a low pressure (about 5psi) that by the time it comes on, the engine is quite often
screwed anyway. My 'blade pressure light never came on until the whole contents of the sump had been dropped (drain plug fell out) and by that
time the engine was on its way out as it had run a big-end, so now Ive got an SPA gauge with a warning light that comes on at about 3bar when Im on
track.
Chris
I've got a 1 bar switch in at the moment anyway, with a 3 bar light it must be on all the time below about 4000rpm??!!
Ben
Yeh it is, but then Im not worried about oil pressure below that sort of revs when on track. At 3 bar its only ever on when i am sitting in the pit
lane (and I can see from the gauge it still has pressure), once out on track it never drops below about 4 bar, so if the light comes on I know I have
a problem straight away.
On the road I knock it down to about 2 bar, then it'll only ever come on when idling, again at this time its easy to check with the gauge that
all is OK.
The ideal scenario is similar to that used on the Digidash etc, whereby you program in limits above certain revs, for example only flash a warning if
the pressure is below 3 bar when revs are above 4k.
Chris
Still comes in when larging it around a corner and you get oil surge though! (that's even with a baffle plate)
Yep, sounds like classic fatigue.....vibration causing cyclic loading.....screw threads causing a natural stress raiser....
Glad you caught it in time....timely warning for all of us....
Mine sits rock solid at about 5.5 bar even in long sweepers, are you getting a bit of surge then Jasper?
The pressure sender has a gauge and switch, and it's the switch side that comes on sometimes when cornering heavily - though I can't
remember what it alarms at.
Spoke to the chaps at ETB and they said not to worry, as long as the oil pressure gauge reads ok after the corner, which it does, then it will be
fine. So far it's only done this at Donny.
Jasper, you can set your pressure warnings up as I described above, to only allow it to warn you below a certain pressure and above a certain rpm. Do
you know what parameters yours is set up to at the moment, it could be that they arent set properly for your engine?
Really you shouldnt get any deviation in pressure right throughout the corner assuming static revs, and ETB simply saying "well as long as it
goes back to normal afterwards" is a bit naive.
Chris
A lot of bikes are fitted with oil level warning lights and not pressure warning lights or are you fitting your own aftermarket kit?.
yours, Pete.
quote:
Really you shouldnt get any deviation in pressure right throughout the corner assuming static revs, and ETB simply saying "well as long as it goes back to normal afterwards" is a bit naive.
quote:
Originally posted by Peteff
A lot of bikes are fitted with oil level warning lights and not pressure warning lights or are you fitting your own aftermarket kit?.
yours, Pete.
I guess the gods were looking down on me the other day, I only needed just over 1 litre to fill the sump to top of
dipstick.................phew
Chris, where did you get your SPA guage from??
Cheers
Ben
Sounds like you were lucky, you obviously didnt loose all the oil so hopefully you should have escaped!
I go the SPA gauge from Rally Design I think, but most of the usual suppliers (Tweaks etc) stock them. Mine is a dual oil pressure/ oil temperature
gauge, with and oil pressure sender connected into the engine where the oil pressure switch used to be (albeit via a 10" long piece of Aeroquip
hose to protect the gauge from vibraton), and the temperature gauge mounted directly in the sump pan.
Chris