T: Fuel Tank VOC Spares Company Ethanol Proof Ewarts Plunger

Rob H

Well Known and Active Forum User
VOC Member
I tied to post this in the VOC Spares company forum to ask the question but it seems we are not allowed to.

The question is that does anyone have any experience of using these plungers and what is the material used that replaces the cork? I am guessing that this is not Viton

From my experience, I fitted these with a little oil and they had a nice smooth action but as soon as the petrol came in contact they began to become tight and now after a couple of weeks they are very difficult to open and require a firm grip of fingers from two hands to operate
 
G

Graham Smith

Guest
Someone once told me that neoprene (the stuff that wetsuits are made of) is a good replacement.
 

Rob H

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VOC Member
Ok did not notice the thread had been moved. Some additional info

I have spoken with the Spares Company and they have noted that they had sold many sets of these but have not heard of any problems so there must be some sets out there in use somewhere.

In fairness they proposed to send another set to try so once these arrive will swop them over and have a look at the originals to try and identify the problem.

Still interested to hear any feedback from members who have installed these.
 

Rob H

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VOC Member
Someone once told me that neoprene (the stuff that wetsuits are made of) is a good replacement.

I think Viton is the accepted solution.

I asked the spare co what material was used but they have no information from the supplier
 

LoneStar

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VOC Member
I couldn't find these on the VOCS site - or are they just listed as T28? Anyway, I installed these:


and had the same problem - the plunger would stick and become very hard to open or close. I put the rings on a rod, spun in the lathe and sanded down the OD a bit, and they now work nicely.
 

TouringGodet

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I like these much better than the other Ewarts "fix it" kit, that supplies a new plunger, with 2 o-rings, one on each end. I want to retain my original plungers on the Shadow.
 

Rob H

Well Known and Active Forum User
VOC Member
I couldn't find these on the VOCS site - or are they just listed as T28? Anyway, I installed these:


and had the same problem - the plunger would stick and become very hard to open or close. I put the rings on a rod, spun in the lathe and sanded down the OD a bit, and they now work nicely.


I could see these working when the outlet of the tap is in the horizontal position but not in the vertical with a bottom outlet. Surely the petrol would leak between the vertical ribbing of the O rings?
 

Rob H

Well Known and Active Forum User
VOC Member
I received the replacement plungers from the spares company to try again, I removed one, cleaned out the tap with brake cleaner and fitted the new plunger (dry this time without any oil as initial lubricant). It has been a week now and the action is nice and smooth and not too stiff to operate.

I put the "faulty" plunger that I removed in a jar of petrol to see if there was any effect on the seal, both measuring the diameter and also a visual inspection. There has been no discernible change after a few days.

In summary I can only conclude that the extreme stiffness of action was due to the petrol reacting with the fine coating of engine oil (for initial lubricant) to form some sort of very sticky substance which prevented easy operation.

In my opinion the new plungers are very good product for the price that solves the ewarts/ethanol issue. The only stipulation is to ensure that taps are cleaned to remove any internal residue, ensuring no sharp edges inside from drillings etc and to install the new plungers dry.
 

LoneStar

Well Known and Active Forum User
VOC Member
I could see these working when the outlet of the tap is in the horizontal position but not in the vertical with a bottom outlet. Surely the petrol would leak between the vertical ribbing of the O rings?

Good point, but they do work. Without actually checking, I think the offset between the inlet passage (angled backwards) and the outlet creates an area in the plunger bore for an O-ring to seal all the way around its circumference, thus sealing.
 

Nigel Spaxman

Well Known and Active Forum User
VOC Member
There is a grease called EZ Turn that you can get from Aircraft Spruce. It doesn't wash away with gas. It works great on the taper type fuel taps to keep them operating smooth.
 
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