Page 8 of 9 FirstFirst ... 6789 LastLast
Results 71 to 80 of 87

Thread: 65 Lotus Seven S2

  1. #71
    Join Date
    Feb 2012
    Location
    Roswell GA
    Posts
    974

    Default

    Lookin' good
    Life happens while you're making other plans
    1995 Caterham Crossflow RHD
    1990 Miata
    2007 GMC Sierra WT
    2013 Mini (Her's)
    2014 Outback
    JOHN DEERE D130

  2. #72
    Join Date
    Apr 2008
    Location
    San Jose, CA
    Posts
    564

    Default

    Quote Originally Posted by SENC View Post
    Whew, re-installing the carbs/intake manifolds and exhaust manifolds on the pre-crossflow is a booger! I used hex key bolts rather that studs, but the angles make getting it all in place tough and getting the bolts tightened nearly impossible. I need to find some angled allen keys, or some other trick! But, they're on - will work on the linkage tomorrow, then possibly start it up.

    Attachment 17026
    very nice! Are both ceramic coated?

    I use 3 different tools to tighten those bolts: one shortened hex-key wrench with a ball end, one shortened hex-key wrench with the shalf bent at a slight angle, and one of these. I use a socket and extension on the hex keys just to be able to apply more torque.

    It also helps to have dowel pins on the intake manifolds, but it's a bit late for that. You'll want to check them occasionally as they do tend to loosen.

  3. #73
    Join Date
    Oct 2019
    Location
    SE NC
    Posts
    68

    Default

    Thanks Dingo. I've purchased a set of stubby ball-end L-wrenchs for next time No, not ceramic coated, just a coat of high-temp paint.

    Name:  20200517_105200 1.jpg
Views: 154
Size:  41.1 KB

    Reinstalled and running. Have some additional tuning to do but got it in the right ballpark for a short drive - enough to tell me I need to do some more tuning on the Elan, this Seven is exhilarating when in the gas!

    I realized I was blowing oil from the breather. The dipstick has registered a bit over the full line since I got it so may just have been overfilled. I took advantage of today's warm-up to change the oil and filter and we'll see how it does next tuning session. I'm not familiar with these pre-crossflows or this breather apparatus - does anyone have any advice?

    Name:  20200517_160522.jpg
Views: 152
Size:  50.0 KB
    Henry
    1965 Seven S2
    1969 Elan S4

  4. #74
    Join Date
    Apr 2008
    Location
    San Jose, CA
    Posts
    564

    Default

    Assuming that the engine is in basically sound condition and therefore the rings are not allowing excessive blow-by, then what you are experiencing is the oil being mechanically thrown out. The breather is directly above the eccentric lobe on the cam that drives the fuel pump.

    I've never seen a breather like that. Most kent's use a breather block and route the pcv hose out of the breather into either a catch tank, the intake, or back into the rocker cover. The latter removes 50% of your breathers though.

  5. #75
    Join Date
    Oct 2019
    Location
    SE NC
    Posts
    68

    Default

    I've been told elsewhere that the breather I have is an early one and should have an elbow on top of it that terms in a pipe (originally to the environment below the car, or preferable to a catch tank then environment). Here is a picture of the elbow:

    Name:  breather elbow.jpg
Views: 127
Size:  12.3 KB
    Henry
    1965 Seven S2
    1969 Elan S4

  6. #76
    Join Date
    Aug 2009
    Location
    Escondido, CA
    Posts
    289

    Default

    I love watching your progress.

    You might want to consider getting an extra thick intake/exhaust gasket. I too have a '62 pre X-flow with the same manifolds. I have found that with the stock gasket the manifold mounting screws tend to back out over time. The thick gaskets (approximately 3/16 inch thick) I'm using now have eliminated that issue. I get them from Ivey Engines. I also use a small O.D. washer under the screw heads from ARP. You can just see the top edge of the gasket in this picture.


    I'm very much interested to see how you handle the crankcase breather system. I've just fabricated a system for my car and installed it this past Saturday. So far it seems to be working properly with no measurable oil consumption after about 140 miles. But the jury is still out.......

    Please continue to keep us updated.
    Last edited by escondidoron; 05-18-2020 at 02:49 PM.
    Ron

    '14 Evora IPS
    '84 Turbo Esprit
    '77 S1 (deceased)
    '62 Lotus Seven S2 109E Cosworth

  7. #77
    Join Date
    Oct 2019
    Location
    SE NC
    Posts
    68

    Default

    Thanks Ron, I used a cometic gasket and know I'll need to tighten after the first few heating/cooling cycles, but hope it will be ok afterward. Will keep your thicker gasket recommendation in mind if not.

    I am curious about the black tubes protruding between the air trumpets.

    I'm also interested in the history of the carbs themselves - I recently bought a pair of Weber DCOE2s as backups that have 2B/2C numbering like yours.
    Henry
    1965 Seven S2
    1969 Elan S4

  8. #78
    Join Date
    Aug 2009
    Location
    Escondido, CA
    Posts
    289

    Default

    Quote Originally Posted by SENC View Post
    I used a cometic gasket and know I'll need to tighten after the first few heating/cooling cycles, but hope it will be ok afterward.
    I have used the Cometic gaskets and find them to be the best in my experience. In my case I found it necessary to keep a set of appropriate tools in my travel case as re-torquing those bolts was a fairly regular service item until I switched to the thicker gasket.


    Quote Originally Posted by SENC View Post
    I am curious about the black tubes protruding between the air trumpets.
    The black tubes are my homemade crankcase vent ports. I did not want to have a catch can that requires servicing and I did not want to simply vent to the atmosphere. I have attempted to design a system similar to that found on modern cars as opposed to the ancient 'road draught tube' that was originally fitted by Ford and Lotus pre 1963. However some compromises have had to be made since due to the multi-inlet-runner carburetor system it was not reasonable to tap into the intake manifold on each cylinder between the carb and the head as there is no common plenum. As a result I have vented to the air cleaners. Here are some pics of the setup and the individual pieces:


    For the front carb. Note that the one for the rear carb is similar except that the tube along the bottom is a continuous pass thru so as to be able to provide a path to the front carb.:



    And the Tee fitting to tie the various ports together:




    It's a fairly simple approach to crankcase ventilation plumbing. I have connected the port on the distributor side of the block to the right angle port on the bottom of the Tee fitting with a 5/16" I.D. hose. The back of the valve cover is fitted with a 3/8" MNPT x AN10 adapter with a 90Deg AN10 push elbow attached. that elbow is connected to the Tee fitting with 5/8" hose. the other end of the Tee fitting is connected to the plenum / port plates on the faces of the carbs. The black tubes that you noticed go into the foam air filters allowing any pumping vapor to be drawn into the carb inlets. I added a port on the back of the air filter socks by cutting / punching a hole with a sharp (knife edge) 1/2" hollow punch. The tubes are 5/8" O.D. The mis-match, along with the barb on the tubes, provides air / debris seal. The filter socks just stretch around the trumpets for mounting. They also fit nicely within the confines of the little S2 air scoop on the left side of the bonnet.

    Here is a view with the filter socks installed:


    After about 150 miles of fairly spirited driving to date the insides of the filter socks are still dry and there is no measurable oil level change in the sump. I am running a semi-dry sump setup. I did make one change to the vent system after I took these pics: I disconnected the 5/16" line that exits below the oil fill cap from the Tee fitting and connected it to a clear plastic fuel filter with a paper element. The other end of the filter is open to the atmosphere. It allows air to pass into the valve cover (or exit as the case may be). So far that appears to be what is happening as there is no discoloration of the paper element. Also, I can detect a slight vacuum on the open filter end if I put my finger over it with the engine running. I have capped off the unused branch on the Tee fitting.

    I made the parts on my friend's 3-D printer out of ABS. After printing I brushed them with a coat of Acetone to promote external layer bonding. I.e. the Acetone melts the outside of the layup together. So far the parts are are holding up to the environment. I'm concerned about both heat and fluid contact long term. We'll see. The ABS should be OK with the mineral oil that I use for engine lubrication. Serious fuel contact would however be an issue. As a precaution I applied a light coating of Hylomar Blue to the inside of the clamping flanges of the velocity stacks when I put everything together as Webers have been known to drip occasionally around the outside edges of the inlet trumpets. I also put a 1/8" wire diameter x 2" O-Ring over the trumpet flanges, on the outside of the clamp ring flange, to act as a washer for the retaining tabs. I thought this necessary as the flat base of the vent plenums would otherwise restrict the tabs from directly contacting the clamp ring outer faces to secure the trumpets.


    Quote Originally Posted by SENC View Post
    I'm also interested in the history of the carbs themselves - I recently bought a pair of Weber DCOE2s as backups that have 2B/2C numbering like yours.
    The Webers on my car came with it at the time of my purchase. Its a Cosworth 109E and according to the Register these are the proper original carbs and manifolds for the engine.
    Ron

    '14 Evora IPS
    '84 Turbo Esprit
    '77 S1 (deceased)
    '62 Lotus Seven S2 109E Cosworth

  9. #79
    Join Date
    Oct 2019
    Location
    SE NC
    Posts
    68

    Default

    Wow, that is beautiful design and work!

    My car originally came with an oil cooler (partially visible in a 1966 photo). The oil radiator that used to sit in the nose and all of the plumbing is long gone, but I have a few pictures from around 2008 that show a rather large "catch can" that was part of the recirculating system.

    Name:  7circa2008-4.jpg
Views: 70
Size:  21.9 KBName:  7circa2008-5.jpg
Views: 67
Size:  20.8 KB
    Henry
    1965 Seven S2
    1969 Elan S4

  10. #80
    Join Date
    Oct 2019
    Location
    SE NC
    Posts
    68

    Default

    Apart and cleaned up. You have to admire the simplicity!

    Name:  20200522_163043.jpg
Views: 45
Size:  73.9 KB
    Henry
    1965 Seven S2
    1969 Elan S4

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •