Oil not returning?

specifications, colours, contract nos, variations etc
Posts: 99
Joined: Tue May 26, 2015 5:47 pm

Oil not returning?

Postby Michael.Brown » Mon Jan 29, 2018 5:53 pm

Hi all,

I may a problem with the W/NG at the moment, and am after some advice. When I took the bike out for a short test ride before purchase I removed the oil cap and noticed that very little oil if any was returning, just air and the odd splutter of oil. The bike ran fine and the engine was, and still is very quiet.

However now I have the bike home I have been checking and fettling a few things and since then, whenever I have started the motor I have seen no return. The oil tank was overfilled so I removed sufficient oil to drop the level to about one inch below the return opening at the top of the tank.

Should I take the bike for a run and then check the return or should I investigate first?

If the latter what is the sequence of checks you would recommend I carry out?

1942 Ariel W/NG
1960 Ariel Arrow
1960 Ariel Leader

User avatar
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 1104
Joined: Wed Mar 23, 2011 10:05 pm
Location: swindon

Re: Oil not returning?

Postby dave.owen » Mon Jan 29, 2018 6:36 pm

Is the delivery side working, shown by the bike wetsumping when running,.
Are the oil pipes the right way round.
Pm me your phone number I'll talk you through a few checks.

AOMCC Treasurer

Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 3422
Joined: Tue May 10, 2011 9:42 am
Location: Victoria.. Australia.

Re: Oil not returning?

Postby nevhunter » Mon Jan 29, 2018 10:27 pm

It's a pretty small amount of oil going around with those small pumps. They always pump some air as the return (scavenge) pump is much bigger than the supply pump. You don't need to fill the oil tank. Half full is plenty but it won't affect the action, and it never gets hot. Normal action is to pump a bit after say 20 seconds running at the most and then it splutters with a bit of oil and a lot of air.. that's normal. You can tip a 1/2 cup of oil down the exhaust rocker box and let it settle and after 15 minutes start the engine and observe the "extra" oil returning, It should pump a more solid steam till the excess is returned. Nev

Return to “W/NG Technical”

Who is online

Users browsing this forum: No registered users and 1 guest