Oil pressure gauge hand adjustment.

[Nick Young]

Hello,
My Eureka oil pressure gauge is not returning to zero (see attached photo).
I can't see any form of internal adjustment for the hand position. Therefore am I correct in assuming that the hand needs to be pulled off its spindle and repositioned. If so how best to do so without causing any damage?
Thanks,
Nick

[Chris Sealy]

Hi Nick. You are correct in assuming that the gauge needs to be dismantled. In order to do that, it will have to be removed from the bike, and on to the work bench. The first thing to do is to carefully prise off the bezel from the rear, remove the rubber seal, and finally the glass.Your rubber seal looks to have deteriorated due to age and may crumble, or the bezel, seal and glass may come off as one piece. Getting the hand off of the spindle can be challenging.Once you reach this stage it is best to remove the mechanism from the case.It will usually be held in by a single nut on the rear of the case.
I don't know what your skill set is.You will need to assess for yourself how best to get the hand off.I have a clockmakers hand remover, but in the past I have made a tool, by cutting a slot in the blade of a small screwdriver, and prising under the dial face. Good luck, Chris.

[Nick Young]

Thanks Chris,
I had managed to dismantle it as far as removing the needle. Have now made dial face protectors out of thin hard plastic. Tried praising off with small leavers but uncomfortable with the amount of force that I am applying. So think I will go the clockmakers hand remover way. But first inorder that I buy the correct type of extractor. Can you please tell me if the point in the center of the hand boss is part of the hand or the end of the shaft that it's mounted upon? As I can't currently tell, as all covered with the white paint.
Nick

[Mick D]

Hi

Here's the needle extractor that I made from a bit of 19mm ERW box section to remove a particularly 'difficult' speedo needle:

Needle Extractor.png (242.87 KiB) Viewed 402 times

Not visible in the photo is a 'key hole' slot to allow the extractor to clear the needle spindle/boss.

Regards Mick

[Julian Murphy]

I think that using a screwdriver blade to lever the pointer off the spindle will result in a bent spindle, and possily more but unseen damage to the mechanism that rotates the spindle.

The little homemade puller shown by Mick D would be the way to tackle this.

But, the question has to be asked, 'Why has the pointer moved by 5 lbs?'.

Is it really at zero pressure, or is there 5 lbs of trapped pressure in the mechanism?

[Nick Young]

Thanks but first to see if this type of puller will work is to know if the point in the center, is the end of its mounting shaft or part of the needle?
The gauge is completely disconnected and open to atmosphere. When I blow into it's tube the gauge operates. So have no idea why it has moved.
Nick

[Mick D]

Hi

The centre component is the instrument shaft.

Regards Mick

[Nick Young]

Ok, many thanks Mick.
I now know which way to go without doing any unesseccery damage.
Nick

[Chris Sealy]

Hi Nick. I notice that the hand in your second photo is in a different position to the first photo. Therefore unless the hand is loose on the shaft, the fault must be in the mechanism. I suggest a careful inspection with a good light and maybe a magnifying glass is required. Chris

[Nick Young]

Hi Chris,
It's in a different position because the gauge has been removed from the case. Allowing the dial face to freely rotate around the spindle and also in relation to the needles position.
Nick