Lotus Elan

Cylinder head oil breather pipe

PostPost by: William2 » Fri Dec 22, 2017 6:20 pm

I have modified the oil breather pipe that comes out of the rear of the cylinder head such that it no longer connects to the carb airbox. I have fitted a right angle copper pipe and connected a length of rubber hose that ends just below the chassis cross member. Am I correct in saying that this tube expels air/gas rather than sucking as I have not currently fitted any gauze filter on the end?
William2
Fourth Gear
Fourth Gear
 
Posts: 943
Joined: 20 Jan 2013
Location: West Sussex

PostPost by: vincereynard » Fri Dec 22, 2017 6:29 pm

Out of interest - why? There would be suction in the airbox, although I seem to recall the original twinks were open to atmosphere.
vincereynard
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1217
Joined: 12 Jan 2015
Location: amersham

PostPost by: Foxie » Fri Dec 22, 2017 8:29 pm

William2 wrote:I have modified the oil breather pipe that comes out of the rear of the cylinder head such that it no longer connects to the carb airbox. I have fitted a right angle copper pipe and connected a length of rubber hose that ends just below the chassis cross member. Am I correct in saying that this tube expels air/gas rather than sucking as I have not currently fitted any gauze filter on the end?


You are correct in saying it blows. More or less, depending on the condition of your piston rings !

However these days it would be considered environmentally friendly to run it to an oil catch tank. I improvised one from a 250ml brake fluid bottle filled with Brillo pads. It sat between the airbox and the pedal box. :)
68 Elan +2, 70 Elan +2s
User avatar
Foxie
Fourth Gear
Fourth Gear
 
Posts: 969
Joined: 20 Sep 2003
Location: Wexford, Ireland

PostPost by: englishmaninwales » Fri Dec 22, 2017 8:53 pm

William2 wrote:I have modified the oil breather pipe that comes out of the rear of the cylinder head such that it no longer connects to the carb airbox. I have fitted a right angle copper pipe and connected a length of rubber hose that ends just below the chassis cross member. Am I correct in saying that this tube expels air/gas rather than sucking as I have not currently fitted any gauze filter on the end?


This is the standard arrangement on both the S3 Elans I have owned (and probably on S1-2 cars too - it was the arrangement on my father's Mk 1 LC). The 90 elbow is rubber with a steel tube located at its lower end at the gearbox. As above, it blows crankcase gases.
1966 Elan S3 Coupe
1994 Caterham 7
englishmaninwales
Fourth Gear
Fourth Gear
 
Posts: 521
Joined: 26 Jul 2013
Location: Ruthin North Wales

PostPost by: mbell » Fri Dec 22, 2017 9:03 pm

Foxie wrote:However these days it would be considered environmentally friendly to run it to an oil catch tank. I improvised one from a 250ml brake fluid bottle filled with Brillo pads. It sat between the airbox and the pedal box. :)


The environmental concern is as much about the fumes exiting the engine block as the mess of the oil. Hence why it's rooted to the engine so the fumes can be burnt on the later standard setup.

Of course that's not great for cylinder number 4 and the system is marginal if the engine isn't in tip top shape.

Personally plan to keep the standard setup but thinking about how to improve it's performance by modifying the out let location in the air box.
'73 +2 130/5 RHD, now on the road and very slowly rolling though a "restoration"
mbell
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1673
Joined: 07 Jun 2013
Location: Austin, TX (UK Ex-pat)

PostPost by: billwill » Sat Dec 23, 2017 12:24 am

The messages and photos in my topic from this point on:
lotus-elan-f19/getting-ogu-roadworthy-again-t26101-75.html#p176701
show my use of standard plumbers parts to modify the breather to use a catch tank.

The catch tank is a cyclists aluminium drinking bottle readily available for ?1 in Poundland etc.

I use a turkey baster with an extension pipe on the front to suck out any collected oil, but so far I have only seen oily water.
Bill Williams

36/6725 S3 Coupe OGU108E Yellow over Black.
billwill
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 4723
Joined: 19 Apr 2008
Location: London UK

PostPost by: Craven » Sat Dec 23, 2017 12:48 am

Something about a DuckBill in my motorcycling days.

140167.jpg and
Craven
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1092
Joined: 14 Sep 2013
Location: south coast uk

Total Online:

Users browsing this forum: No registered users and 13 guests