Oil Light suddenly comes on

[rogerowen]

My 1300 Dolomite oil light suddenly came on last night. Thought it might be a sender problem, but if I rev the engine very high the light starts to dim very very slightly. I've ordered an oil pressure test gauge - and I wonder if anyone can advise what pressure reading I should hope for. Thanks.

[tony g]

Dont know specific pressures but the light comes on around 5 psi if working correctly. If you had 30 psi at idle warm then 60 psi at 3000rpm I'd say its ok. If its not then its strip down time.

Tony

[Triumph1300]

40 to 60 psi, 2000 rpm hot engine is the quoted spec

[rogerowen]

Thanks for the data. What I find strange is that the oil light appeared so suddenly. Engine sounds OK (apart from the usual Triumph dry top end noise for a second or two at start up), under load there's no obvious big end clatter. There's some acceleration hesitation which is cured with be heavier right foot - now wondering if this is partial seizure kicking in (reduced by more throttle) - i.e. increase to oil pressure. I had reckoned the faltering acceleration to be fuel related (nasty old WaxStat carb). Engine is not burning oil, oil is clean, tick over far too high, and on switch off there is some clatter coming from somewhere.

Hopefully the oil pressure test gauge I've ordered will arrive for the weekend. Then I'll know for sure if I have a bottom end rebuild on my hands.

[Jon Tilson]

Take off the switch, spin on starter and observe for spurt of oil. If no spurt then immediate strip. If there is a spurt then its the sender.
Order new and carry on without worrying.

These engines need a non return valve in the oil filter. Most now dont have one...so spin on the starter before pulling choke top fire up to get the oil round before the engine is under load.

Jonners

[rogerowen]

Take off the switch, spin on starter and observe for spurt of oil. If no spurt then immediate strip. If there is a spurt then its the sender.
Order new and carry on without worrying.

These engines need a non return valve in the oil filter. Most now dont have one...so spin on the starter before pulling choke top fire up to get the oil round before the engine is under load.

Jonners

Good tips, thanks. I've now got the tick over down to around normal and can hear the big ends clonking. I'm hoping to get away with new big end shells (engine in the car), and a new oil pump - which I guess has failed.

[Jon Tilson]

May also be worth checking the oil pressure relief valve under the big external hex plug. It may have a broken spring and be stuck open.

The oil pump drive is pretty robust on this engine, so its hard to see how that could fail suddenly. For once sadly the green light has done a good job. Jod Clark has good quality bearings if you look at recent threads.

Jonners

[rogerowen]

Thanks everyone. The good news...... The oil pressure test gauge arrived and gives a reading of 40 psi at tick over and 65 psi at around 2500 rpm with a warm engine. The noise I thought might have been big end clonk actually seems to be coming from the alternator - bearing failing? Sigh of relief, an alternator replacement is going to be a lot easier than a bottom end re-fit that's for sure!

[mahony]

Thanks everyone. The good news...... The oil pressure test gauge arrived and gives a reading of 40 psi at tick over and 65 psi at around 2500 rpm with a warm engine. The noise I thought might have been big end clonk actually seems to be coming from the alternator - bearing failing? Sigh of relief, an alternator replacement is going to be a lot easier than a bottom end re-fit that's for sure!

Now there's a happy chappie , as you say alternator a much easier fix than a bottom end rebuild

[tony g]

Good news Remove fan belt and run it to see if noise goes away

Tony

[rogerowen]

Good news Remove fan belt and run it to see if noise goes away

Tony

Yep, thought about that - will try that tomorrow. I spent a while using my stethoscope (long 1/2" drive extension to my ear), placing it to the sump, Block, Rocker cover, timing cover, and water pump - but the noise is much louder at the alternator.

[rogerowen]

Thanks everyone. The good news...... The oil pressure test gauge arrived and gives a reading of 40 psi at tick over and 65 psi at around 2500 rpm with a warm engine. The noise I thought might have been big end clonk actually seems to be coming from the alternator - bearing failing? Sigh of relief, an alternator replacement is going to be a lot easier than a bottom end re-fit that's for sure!

Now there's a happy chappie , as you say alternator a much easier fix than a bottom end rebuild

Yes, very happy. I was thinking the worst and already bought a new oil pump - oh well it might come in handy.....?

[cliftyhanger]

Yes, very happy. I was thinking the worst and already bought a new oil pump - oh well it might come in handy.....?

I would be checking the new oil pump clearances. Many are out of tolerance from the box, worse than the one they are bought to replace
Unless things have changed recently, or it is a stanpart one.

[rogerowen]

Yes, very happy. I was thinking the worst and already bought a new oil pump - oh well it might come in handy.....?

I would be checking the new oil pump clearances. Many are out of tolerance from the box, worse than the one they are bought to replace
Unless things have changed recently, or it is a stanpart one.

I bought 'New Old Stock' apparently over 20 years old - so hopefully it's a good one. I'll probably stick it back on Ebay.
It's a tragedy about new parts for classic cars - the quality is just so poor!