Dave sorted oil pump while the mag was being sorted. Got them both back onto the bike and fired it up to continue with the fettling. Next day found a small patch of oil underneath the bike. Eventually worked out that it's pumping oil through the crank bolt. Finally had a chance to look at it today. The bolt is a new replacement and has a disc that floats back and forth. The bolt that was in the engine has a ball and spring. Not been able to find any suitable images to work out what's what. Is the new one correct, or is something a miss.
1960 model 31 deluxe.
Pumping oil
-
- Posts: 291
- Joined: Sat Jan 14, 2017 11:48 am
- Location: WEST MIDLANDS UK
- Duncan
- Member
- Posts: 2131
- Joined: Thu Jul 10, 2003 1:00 am
- Location: HAMPSHIRE UK
Re: Pumping oil
Hi Jason
Are these the parts?
The loose flap should seal when the crankcase is pressurised (pistons travelling down) and let air in when the engine is on the compression/exhaust stroke with the pistons travelling upwards, you should not get any significant oil through it. (EDIT - this description is the wrong way round, sorry for any confusion )
Is the oil coming from the engine breather behind the primary chaincase?
Are these the parts?
The loose flap should seal when the crankcase is pressurised (pistons travelling down) and let air in when the engine is on the compression/exhaust stroke with the pistons travelling upwards, you should not get any significant oil through it. (EDIT - this description is the wrong way round, sorry for any confusion )
Is the oil coming from the engine breather behind the primary chaincase?
You do not have the required permissions to view the files attached to this post.
Last edited by Duncan on Sat May 19, 2018 7:39 pm, edited 1 time in total.
-
- Posts: 291
- Joined: Sat Jan 14, 2017 11:48 am
- Location: WEST MIDLANDS UK
Re: Pumping oil
I'd say it's 025526. I have taken a couple of pictures, but haven't worked out how to load them up. But what I have noticed when the disc is out (down stroke) there's a gap visible behind it. And when in (up stroke) it would appear to close the passage. Fairly certain that it is pumping through the bolt. To be sure, I'll have to reassemble it with the case off and run it up again.
- les ward
- Member
- Posts: 380
- Joined: Mon Jan 01, 1990 12:00 am
- Location: WILTSHIRE UK
Re: Pumping oil
How long has it been left standing. Over time the sump will gradually fill with oil (wet sumping). Try draining the oil from the sump and then see if it still happens.
-
- Posts: 17
- Joined: Tue Apr 17, 2018 6:45 pm
- Location: North Yorkshire
Re: Pumping oil
"The loose flap should seal when the crankcase is pressurised (pistons travelling down) and let air in when the engine is on the compression/exhaust stroke with the pistons travelling upwards, you should not get any significant oil through it."
I'm new to AMC bikes, but I do have experience of how breathers work and I am a bit confused about the operation of the valve.
If it closes when the pistons are descending, then the crankcase will be pressurised, surely? Then, if it opens when the pistons are ascending, it will draw air into the crankcases.
In my experience, a breather's function is to expel the compressed air beneath the pistons and, as far as is possible, not allow it to suck any more in as the pistons ascend.
Or am I missing something?
I'm new to AMC bikes, but I do have experience of how breathers work and I am a bit confused about the operation of the valve.
If it closes when the pistons are descending, then the crankcase will be pressurised, surely? Then, if it opens when the pistons are ascending, it will draw air into the crankcases.
In my experience, a breather's function is to expel the compressed air beneath the pistons and, as far as is possible, not allow it to suck any more in as the pistons ascend.
Or am I missing something?
Allan.
-
- Posts: 291
- Joined: Sat Jan 14, 2017 11:48 am
- Location: WEST MIDLANDS UK
Re: Pumping oil
Not wet sumping any more. Pump has been sorted. Spoke to dave and have a few things to look at. Hopefully next week. It needs to be on the road now.
- Duncan
- Member
- Posts: 2131
- Joined: Thu Jul 10, 2003 1:00 am
- Location: HAMPSHIRE UK
Re: Pumping oil
Allan, you are missing nothing and I am a complete numpty and typed the description the wrong way round, I have no other excuse other than incompetency.I'm new to AMC bikes, but I do have experience of how breathers work and I am a bit confused about the operation of the valve.
-
- Posts: 17
- Joined: Tue Apr 17, 2018 6:45 pm
- Location: North Yorkshire
Re: Pumping oil
Hi Duncan. Please don't berate yourself! I'm grateful for your reply because it confirmed that I wasn't having a 'senior moment!'
Allan.