Hybrid - engine stop/start - Engine life

[Britprius]

21 hours ago, NemesisUK said:

Which is why I was asking about the possibility of an 'off-line' electric oil pump. Perhaps as the engine is spun up using the powerful traction motor there is significant oil pressure built up before any loads are applied to the ICE?

In one of my previous post I mentioned the fact that I was "and still are" thinking about fitting a pre-lube system to remove the annoying rattle from the VVT system.

The system is very simple using a sealed pressure bottle which is fed with oil from the bottom through a solenoid valve.

When the engine is running, and has oil pressure the pressure of the oil compresses the air in the bottle as it fills. When you press the start button an ignition feed opens the solenoid for a few seconds allowing the oil under pressure to travel round the engine. Because there is a delay before the engine starts in a hybrid the engine will have pressure before it turns. Once up and running the oil will flow back to refill the bottle "ready for the next start" even though the solenoid is closed because the solenoid only shuts off in one direction of flow.

This would allay any fears of lack of lube at startup, and also remove the VVT rattle. 

There is such a system ready produced on the market, but it would be very easy to make your own system.

John.

www.ebay.co.uk/itm/Auto-Engine-Pre-Lube-Oiler-Tank-Could-Save-Your-Engine

[NemesisUK]

Neat idea, like it.. But sometimes there is a really significant delay between power on and ICE start,.

How might it integrate with the stop/start of the ICE once up to temp and supporting the traction motor? Very little time delay to start up 

[Britprius]

52 minutes ago, NemesisUK said:

Neat idea, like it.. But sometimes there is a really significant delay between power on and ICE start,.

How might it integrate with the stop/start of the ICE once up to temp and supporting the traction motor? Very little time delay to start up 

In the case of restarting when the engine has already bean running there will at the instant of starting be two oil supplies plus the oil in the system will not have totally drained back to sump. The cars own oil pump and a supply of oil at a pressure that is the maximum that the engine runs at. "The stored pressure". With both supplies the rate of oil flow at start must be doubled halving the "un-lubed time". Using 0w20 oil also speeds up the process. 

John.

[NemesisUK]

But would there need to be a modification to the solenoid opening trigger as the IGN is already live?

[Britprius]

14 hours ago, NemesisUK said:

But would there need to be a modification to the solenoid opening trigger as the IGN is already live?

No the trigger for solenoid is timed it only opens for a few seconds at ignition on or may be in the case of a hybrid after first cold start, it could be triggered by the engine run signal. This could easily be arranged.

John

[NemesisUK]

That's what I was wondering, the engine run signal. Could be interesting, trying to find a pickup point for that signal.

[Britprius]

4 minutes ago, NemesisUK said:

That's what I was wondering, the engine run signal. Could be interesting, trying to find a pickup point for that signal.

There must be a supply for the ignition coils, Or perhaps better still the fuel pump.

John