HT5 Oil Pump

[Ian.Hamilton]

Hi fellow members, can anyone advise?
A part of my ongoing HT renovation I decided to take of the oil pump as heard this can be troublesome and all parts be checked for cleanliness and movement. This I did {but not very well}. When removed and stupidly without thinking laid it aside to come back later to find a pool of oil. I duly cleaned this up and think I disposed of one of the ball bearings AND this is the question "Should there have been two on the engine face as one was held in its recess and I am assuming there should be two? if so does anyone know what Dia they are and indeed if there are two would they be the same diameter. Would the club have this sort of thing? finally for now!! would it be better to replace the pump for a new one if they are such problematic things. Again any help much appreciated
Regards all
Ian

[dave.owen]

The oil pums generally give no trouble, when the pump is removed oil drains from the oil tank. See diagram balls go in from underside.check draganfly for parts.

Dave

[will_curry]

Ian,

Read the notes under 'Timing case' on the Draganfly website for single engines.

I'll echo what Dave says about pumps and trouble. Issues are almost always due
to dirty oil. All my Ariels including my HT are running on their original pumps. HTs
generally don't do that many miles compared to roadsters although they can be
quite difficult miles and the engines don't need oil pressure nor do they need that
much oil being roller bearing engines.

It'll only be a matter of time before our administrator moves this thread to four stroke
technical help.

[Ian.Hamilton]

Thank you both for your help and information, I will have a look at this with fresh eyes. what I am not really understanding is, When I took the pump off the casing there was a ball in that casing? I will take the pistons out and check if both balls are there.
Again m thanks Guys much appreciated.
Ian

[Simon.Gardiner]

Ian - the singles may have one or two additional ball valves -placed in the timing cover, as 'backups' in case of failure of one of the pump valves.
(There's an Ariel Service Bulletin about these which may help further - see no. 125 in the doc repository here:
http://www.arielownersmcc.com/members_o ... index.html )

(And with admin hat on - topic moved to 'technical help'....)

SG

[JohnnyBeckett]

hi i would buy a new pump from Morgo that gives a better flow and return and oil pressure , ( the heart of a engine is the oil and pump )

[Vincent.vanGinneke]

There is one ball in the timing chest in the delivery line.
This ball is spring loaded and is being held in the timing chest by a small round hollow plug that has a 'ridge' across to not let it being flush with the oil pump body . On the 'inside' e.g. the side that holds the ball, it has a camfer .
But, the ball with spring and plug it is not needed , Ariels with a oil pressure gauge need the ball for maintaining pressure in the oil line going up to the valves.
Without the ball, oil still goes up but a gauge wont work.
correct me if I am wrong but I think Ariel did not fit this arrangement in the early fifties only to re-fit the arrangment again later in the fifties.
I have this small plug (somewhere...) if I can find it I make a picture.

found it in my pc...

as you can see, first the spring goes in, then the ball and last is the plug

[david.anderson]

Apart from the plug, ball and spring in the delivery oil way, as posted above by Vincent, post 56 Ariel used a loose ball and spring behind the oil pump in the return line as a back up in case of failure of the oil pump. Details are in the link posted by Simon as well as the modification necessary to the timing case for pre 56 singles to use this setup. I would always recommend fitting the back up systems to both delivery and return oil lines. I have experienced 2 separate return oil failures in 50 years of riding my VH. In each case just a bit of grit under the ball and stopping the suction. On the first occasion a friend was riding behind me and noticed my bike spraying oil, and covering him. With the return oil not being pumped to the oil tank my VH had wet sumped and was pushing oil out the crankcase breather. I pulled over, quickly realised the problem, removed the oil pump roadside and was going again within a few minutes. Years later on the second occasion however, with the return oil not working and lubricating the top end, the exhaust valve seized in the guide in the open position, stopping the engine. I then fitted the back up ball and spring to the timing cover, and modified the timing cover all my pre 56 singles to fit the back up ball and spring.
David.

[Ian.Hamilton]

Again my thanks to every one, I don't think I made myself too clear on my original post on the oil pump. Just to clarify, I was not talking about the two balls contained within the oil pump body but another which seemed to be behind the flange on the pump itself. Thankfully you Gurus picked up what I meant and have provided me with good information. I now know there is only one ball (not two as I had feared) also there should be a spring and a plug which I will now look at.
I sure am glad I joined the AOMCC and appreciate the help you guys have given me.
Best Regards
Ian

[paul.jameson]

Please study the Service Bulletin mentioned in Simon Gardiner's post, along with David Anderson's post.