Zero oil pressure

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Zaphod
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Zero oil pressure

Post by Zaphod »

I have finally got my engine started and running, actually it was not that dramatic in the end. However I do have a bad inlet tappet on 2 or 3. Of more concern is the oil guage showing zero pressure, the sender has two terminals however there seems to be nothing to attach to the second terminal. The rev counter and voltmeter work as does the temperature guage. The fuel guage read zero as well but that might be because I only put 5 litres of petrol in the car! Oil is circulating, as I undid the oil filter to check and found oil in the filter and the pipes to the oil cooler
Is it worth grounding the wire in the sender to see if the guage then reads full deflection?
As a second question the temperature reached just below 100 before I shut it off, but the fans did not come on, what temperature should they do so and if I bridge the otter switch should they run? They did when I tested them before fitting them to the radiator
Of all the things I have lost I think I miss my mind the most...

1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel

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Hawaiis0
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Re: Zero oil pressure

Post by Hawaiis0 »

Fans on about 85 degrees. Jump the switch to see if run manually ( ignition on ).
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Alan_M
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Re: Zero oil pressure

Post by Alan_M »

For oil pressure I would suggest fitting a oil pressure tester to see what your pressure actually is.

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MetBlue
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Re: Zero oil pressure

Post by MetBlue »

The oil pressure gauge needs 3wires.
A permanent 12v and Earth, plus the signal wire from the sender.

For the fans, I ran two wires from the otter switch to a manual switch I have inside the car. Maybe one day I'll get confidence in the thermal switch activating reliably, but I'm not there yet.

Tony
What goes together.... Must come apart.

Zaphod
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Re: Zero oil pressure

Post by Zaphod »

OK, todays progress..

Bridging the otter switch with a bit of wire brought the fans to life, so it looks like the otter switch has failed, vaguely considering putting a Schmidt trigger on the temperature sender for the guage, but might be easier to replace the otter switch.

The oil pressure guage shows full scale deflection when the oil pressure sender is disconnected so it looks like the sender had failed of I have zero oil pressure, but it’s now hot probably an hours idling on it with no ill effects.. and as I say the brand new oil cooler and filter have filled up with oil
Of all the things I have lost I think I miss my mind the most...

1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel

Zaphod
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Posts: 242
Joined: Mon Aug 23, 2021 21:38
Model: Excel SE
Colour: Blue
Year: 1990
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Re: Zero oil pressure

Post by Zaphod »

Opened up the oil pressure sender, it was full of corrosion, so I would guess that’s why the guage did not work!
Of all the things I have lost I think I miss my mind the most...

1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel

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Hawaiis0
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Re: Zero oil pressure

Post by Hawaiis0 »

What is your gauge range? Have you got one yet?

A few on fleabay at the moment

This one is 50 quid with best offer.

https://www.ebay.co.uk/itm/173887956888 ... ondition=4
Nothing is fool proof. Fools are clever!

Zaphod
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Re: Zero oil pressure

Post by Zaphod »

Hawaiis0 wrote:
Wed Apr 13, 2022 17:17
What is your gauge range? Have you got one yet?

A few on fleabay at the moment

This one is 50 quid with best offer.

https://www.ebay.co.uk/itm/173887956888 ... ondition=4
The gauge is working fine, as is the wring to it, the sender on the engine is utterly destroyed internally! so I need a new one.. just the sender

Stew
Of all the things I have lost I think I miss my mind the most...

1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel

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Hawaiis0
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Re: Zero oil pressure

Post by Hawaiis0 »

Zaphod wrote:
Wed Apr 13, 2022 17:45


The gauge is working fine, as is the wring to it, the sender on the engine is utterly destroyed internally! so I need a new one.. just the sender

Stew
Sorry must read harder. 3/10 see me after school :oops:
Nothing is fool proof. Fools are clever!

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Tanz
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Re: Zero oil pressure

Post by Tanz »

I purchased a new sender unit from JG Supplies back in 2019 Part no 970946 £24.99.

Image
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Hawaiis0
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Re: Zero oil pressure

Post by Hawaiis0 »

Thanks Phil, I just ordered one for the bottom drawer in case the new engine needs one.

Use JG suppiles Ebay site and save £3.50 on postage from JG Supplies web page - silly eh!
Nothing is fool proof. Fools are clever!

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