oil light on rev counter
 

i notice under hard acceleration on 1st 2nd and 3rd the little red light flicks on i been told that this aint a oil level indicator but a oil pressure light i have to correct amount of oil in my 748 is it normal for it to come on or is something up im using Castrol GP4 oil

its often the sender unit that is faulty
pull out the wires have a look down the hole , if theres oil in there it's on it's way out

its also the classic early signs of an oil pressure switch failing, its down by your right foot, about 15 quid for a replacement if i remember rightly ...

hole ?????

what hole is that ?

the hole in the top of the sender unit that the wires plugs in to
it's next to where you put the oil in.

Hi, on my 2000 748 i had the same problem in 1st,2nd and 3rd at ~7000 rpm, red light flickering. Measured the oil pressure and everything was ok. Changed the oil switch and still did the same.

I removed the oil and its colour was brown-caffe-latte. Practically i had water in the oil because of a cracked head on the vertical cylinder.

Hope you don't have the same problem... try by changing the oil switch

Paul>
I do believe Glyn and Dibble are talking about the same thing.

if the head is craked wont i lose power ???? the other day i had 170 on the clock lol yes i no thats not guna be true but it looked great the bike seems powerfull threw past exsperience when ur head is damaged power is lost but i have the problem of water getting pressurised i really hope my cylinders arnt cracked but if they are how much will it cost to repair ????????? eeeeeeeeeek

Don't worry about the complex stuff like cracked cylinder heads until you've checked out the simple stuff first...

Are you SURE that the oil level is OK? You say the light flickers on under hard acceleration, that might be because the oil level is marginal and the pressure might be dropping if the oil surges away from the pump pickup...just a thought.

Could also mean that you need an oil change, when was the oil last changed? Oil does break down under the pressure, heat of the engine and becomes thinner with age so the lack of pressure could be down to oil that's past it's best.

If anything is broken t's far more likely to be the oil pressure switch (which will only cost about £30 to swap over) than a cracked cylinder head.

Mind you, I wouldn't want to be doing an indicated 170 with any doubts at all about the oil pressure...not without one hand on the clutch anyway.

swap the switch
change the oil
if that don't work, get it checked over

its just been serviced and the oil is at the correct level i notice sometimes it flickers on idle so i think its the switch that has gone ill sort it out after the moto gp weekender cheers for the help

check the switch...

mine was running at 150mph with the head cracked and the the main crank bearing knackered (when they open the cranckcases the bearing had no textolite cage anymore and the balls were moving freely in the bearing)... and if you can imagine, then engine was sounding so sweet!!!!

i don't want to scare you, but mine's a real experience that began with a question such as yourself... "why is the oil light flickering under hard acceleration?"

anyway, you shouldn't take one isolate experience as a general one

Good luck

check the switch...

mine was running at 150mph with the head cracked and the the main crank bearing knackered (when they open the cranckcases the bearing had no textolite cage anymore and the balls were moving freely in the bearing)... and if you can imagine, then engine was sounding so sweet!!!!

i don't want to scare you, but mine's a real experience that began with a question such as yourself... "why is the oil light flickering under hard acceleration?"

anyway, you shouldn't take one isolate experience as a general one

Good luck

ok cracked head how much will that cost to replace ?? parts and labour ?? will a compression test tell me if the head is cracked or does it have to be stripped?

Calm down, don't panic.............lol.......

I do not think for one moment it will be the head, just start at the beginning and check levels, sender etc.

I changed the oil on my old Senna last week, I noted on re-filling her she took less oil than usual but the level was perfect even after running the engine and yet 2 days later the oil suddenly settled and she needed a good top up.

If it does turns out to be a head I have 2 completely refurbished ones heres complete and ready to fit. New guides, valves, rockers etc. Drop me a PM if you get desperate.

thing is it was flickering before i had it serviced and when they serviced it they said i had good compression in both cylinders my water sytem kept pressurisin but that was due to the cap being faulty all tho it did do it again the other day

If the engine has "gone" ie, big end, bearings, shells, whatever, then the engine should sound different, slightly more rattly than normal!! You might not notice any power difference till the engine really lets go.

But that is all worst case scenario... Lots of people seem to fix it with the oil switch thingy

i changed the engine to a 916 on mine