Lotus Elan

Weber tuning

PostPost by: "Don Fysh" » Sun Sep 17, 2000 4:32 pm

Installed new O-rings, Plugged headlight vacuum connection, Reset points
gap.
Dwell now 60.
Idle is much better. Don't know what helped.
Problem: I can't adjust the timing because today the timing light won't
work. Worked OK yesterday. Always something.
Once I get timing set I will complete the tuning and find out if the other
problems went away. So far slow return to idle still seems to be still
there though.

Thanks to all who offered suggestions.
Don
"Don Fysh"
 

PostPost by: gobw2 » Sun Sep 17, 2000 5:25 pm

Glad to learn of your progress. Don, bringing the dwell back to spec
means the points open a bit later. This means timing willbe a bit
retarded from where it was. The significance depends on where it was, but
you may find that when yyou reset the timing you can lean the idle
mixture a tad.
If you have access to an exhaust gas analyzer and a vacuum gauge, they
would be handy now.
One other thought - if you had a vacuum leak, and balanced with it,
balance will be out with leak corrected. Rebalancing will smooth things
a bit more. Slow return to idle - the vacuum gauge can help - enginein
good shape, no leaks - if I remember right - should get about 26 at idle.
When the throttles close, vacuum should go up instantly - if it does
not, then look for reason - where is engine getting it from? sticky
throttles, leaky intake valves - too little valve clearance, another
vacuum leak? - George
On Sun, 17 Sep 2000 11:33:13 -0500 "Don Fysh" <***@***.***> writes:
-------------------------- eGroups Sponsor

Installed new O-rings, Plugged headlight vacuum connection, Reset
points
gap.
Dwell now 60.
Idle is much better. Don't know what helped.
Problem: I can't adjust the timing because today the timing light
won't
work. Worked OK yesterday. Always something.
Once I get timing set I will complete the tuning and find out if the
other
problems went away. So far slow return to idle still seems to be
still
there though.

Thanks to all who offered suggestions.
Don


The Lotus Elan mailing list is provided by the LotusElan.net
website.


gobw2
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PostPost by: "Don Fysh" » Sun Sep 17, 2000 9:54 pm

This has not been a good day.

I was merrily working away on my Webers, rebalancing, readjusting timing,
tuning, troubleshooting per all of the good suggestions I have been
receiving. I looked up and saw blue smoke coming from under the dash.

Panic time!!! Grabbed the fire extinguisher, turned off the ignition,
quickly disconnected the battery. Smoke abated. Fortunately didn't need
the extinguisher!!

Looked under the dash. The wiring loom is fried. I'm not sure what caused
it yet. I was recharging the battery at the time (2 amp setting). Could
that do it? I also had a dwell/tachometer connected.

I guess I won't be doing any more Webering for a while. I'll have to pick
up that thread again in the future.

Right now I am looking at replacing the wiring loom. Does anyone have
good/bad experience with replacement looms from US sources?

Bummed,
Don
"Don Fysh"
 

PostPost by: gobw2 » Mon Sep 18, 2000 1:14 am

yes, recharging the battery while the engine is running can cause that
and more - remember -the generator regulator is trying to control system
voltage. You are putting in power from another source, and It cannot
control. This will cause regulator contacts to
burn, possibly sticking and damaging weakest link. I am amazed that 2 amp
charger could do it though - rough guess - 5 amp or greater.
Personally, I would not buy a new harness. typically, not everything
will be damaged. The wires themselvew will still be intact, so you can
follow them to see what they do, and to get their color from an
undamaged section. This would be a good time to get a fuse block and
split off circuits. put wiper, heater fan, signals, cigar lighter,etc
on own circuits with lower rated individual fuses. As I said in a
previous reply a week ago, the 30 amp fuses are too large to protect most
of the wiring. Good time to get rid of the bullet connectors too.
go to an electrical supply house and buy THHN/MTW wire - rated 90 c .
MTW (machine tool wire ) is an oil, moisture and gasoline resistant
coating - that and higher temp rating will last indefinitely. Use
nothing smaller than 14 gauge for heater fan, wiper motor,cigar lighter,
headlights. 12 gauge is better. Wire from starter relay terminal to
fuse block should be at least 10 gauge. Wire is available in variety of
colors from house. Do NOT buy that cheap, low temp thermoplastic stuff
in auto parts stores.
You will have a better loom for only a few dollars, and you can run it
best possible way. I recomend fuse block inside car - on back side of
firewall, where you can get it , and oil/elements cannot.- glovebox area
is pretty open. Never wrap stuff tight - we derate wires when bunched up,
because heat cannnot dissapate.. worked as electrician, built a few
looms myself. Don - it's a piece of cake, really. George
On Sun, 17 Sep 2000 16:54:10 -0500 "Don Fysh" <***@***.***> writes:
-------------------------- eGroups Sponsor

This has not been a good day.

I was merrily working away on my Webers, rebalancing, readjusting
timing,
tuning, troubleshooting per all of the good suggestions I have been
receiving. I looked up and saw blue smoke coming from under the
dash.

Panic time!!! Grabbed the fire extinguisher, turned off the
ignition,
quickly disconnected the battery. Smoke abated. Fortunately didn't
need
the extinguisher!!

Looked under the dash. The wiring loom is fried. I'm not sure what
caused
it yet. I was recharging the battery at the time (2 amp setting).
Could
that do it? I also had a dwell/tachometer connected.

I guess I won't be doing any more Webering for a while. I'll have
to pick
up that thread again in the future.

Right now I am looking at replacing the wiring loom. Does anyone
have
good/bad experience with replacement looms from US sources?

Bummed,
Don


The Lotus Elan mailing list is provided by the LotusElan.net
website.


gobw2
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PostPost by: gobw2 » Mon Sep 18, 2000 1:19 am

don - one other thought - make wery sure your engine and battery are well
grounded. I run 2 braided grounds - I added second at trans mount -
shorter route, less movement and gave me better starting power. I also
added a second at battery to other chassis bolt. - I did not like voltage
drop at lotocone bolt when starter engaged - actually got warm in cold
weather starting. George

On Sun, 17 Sep 2000 16:54:10 -0500 "Don Fysh" <***@***.***> writes:
-------------------------- eGroups Sponsor

This has not been a good day.

I was merrily working away on my Webers, rebalancing, readjusting
timing,
tuning, troubleshooting per all of the good suggestions I have been
receiving. I looked up and saw blue smoke coming from under the
dash.

Panic time!!! Grabbed the fire extinguisher, turned off the
ignition,
quickly disconnected the battery. Smoke abated. Fortunately didn't
need
the extinguisher!!

Looked under the dash. The wiring loom is fried. I'm not sure what
caused
it yet. I was recharging the battery at the time (2 amp setting).
Could
that do it? I also had a dwell/tachometer connected.

I guess I won't be doing any more Webering for a while. I'll have
to pick
up that thread again in the future.

Right now I am looking at replacing the wiring loom. Does anyone
have
good/bad experience with replacement looms from US sources?

Bummed,
Don


The Lotus Elan mailing list is provided by the LotusElan.net
website.


gobw2
Fourth Gear
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Posts: 968
Joined: 25 Sep 2003

PostPost by: Donald Lee Butler » Mon Sep 18, 2000 1:44 am

Don,
The problem probably is the rubber insulation used on British cars.
The rubber rots and the wires sooner or later touch. My ?lan had the
same problem as yours but before it was 10 years old!
I once read about a MGB that the starter turned on while parked and
didn't stop until the battery was disconnected. The writer's comment
was to never leave the car in gear when up on jack stands because just
five minutes before the starter went crazy he was under it.
I found a site that deals with British wiring, some of the tips may
help you install the new harness.

http://ourworld.compuserve.com/homepage ... iring.html

Don Butler
45/9469


Don Fysh wrote:

. . . I looked up and saw blue smoke coming from under the dash.

Panic time!!! Grabbed the fire extinguisher, turned off the ignition,
quickly disconnected the battery. Smoke abated. Fortunately didn't need
the extinguisher!!

Looked under the dash. The wiring loom is fried. I'm not sure what caused
it yet. I was recharging the battery at the time (2 amp setting). Could
that do it? I also had a dwell/tachometer connected.

Bummed,
Don
Donald Lee Butler
 

PostPost by: "Roger Sieling" » Mon Sep 18, 2000 12:06 pm

I can't imagine how this silicon thing can even help much. You do realize that Webers have ball bearing on the throttle shafts, don't you? Wiggling the shafts is a trick used on carbs such as SU or Strombergs or older DCO-3 sand cast Webers, which have bushed carb bodies. The shafts and the bushingswear, causing looseness which can be felt. Biggest problem with DCOE Webers I've seen is that dirt gets trapped in the bearings or well meaning mechanics soak them in cleaning solvents which then washes out the lubricant. Then they get stiff and don't want to open and close. You might try lubing them with one of the adapters which has a grease fitting on one end and a hypodermic needle on the other. Remember that the seal outside the bearing is only a leather washer.

Roger

>> ***@***.*** 09/16/00 12:24PM >>>

Arno
I have a spare set of O rings for the intake manifold. I will try them this
afternoon. I thought the current set looked OK when I installed the carbs
and I did take care with the gap on the Thackery washers but I will try the
new O rings.

I will also try the sealing trick on the butterfly shaft seals that Mike
suggested. That sounds promising.

I'll let you know how I made out.

Thanks
Don
"Roger Sieling"
 

PostPost by: "Roger Sieling" » Mon Sep 18, 2000 12:15 pm

Another thing to check on your carbs while they are off the car is to look inside the throat, where the idle mixture needle seats. Some people who don't know their own strength could have owned or worked on your car before and I've seen DCOEs where the screws have been tightened down so much that they have broken through and there are little cracks eminating from the needle valve's hole. This makes it imposible to set right.

Roger

>> ***@***.*** 09/16/00 03:43PM >>>

One last thing on the cause of hunting idle
There could be some "play" at the linkage fitting over the butterfly spindle . The spindle is a round shaft , flattened on two oposing sides with the linkage having a similar " ovalish" hole that fits over the spindle. More often than not there is some " play" in this fit and this is often a cause for perfect balance between the carbs going astray. It helps to peen the opening in the linkages to ensure a tight fit ( oo'er !)
Arno
"Roger Sieling"
 

PostPost by: "Roger Sieling" » Mon Sep 18, 2000 12:19 pm

Check the ignition timing also. The specs in the shop manual are STATIC, meaning engine NOT running.
Roger

>> ***@***.*** 09/16/00 07:25PM >>>

Thanks for the suggestions Arno, Keith, John and Mike,

I smeared some vaseline around the vacuum tubing to seal it up but it made
no difference. A good thought though!!

I also squirted some oil around the O rings and the end connections on the
butterfly spindles. No joy.

These suggestions seem to be directed toward the hunting idle. Are air
leakage problems also possible explanations for the hesitation when blipping
the throttle and the slow return to idle after blipping?

I checked the dwell and it was 54. The manual says 60 +or- 3. Is 54 so far
out to cause a problem?

This afternoon I replaced the O rings and blew out the carb jets for good
measure. I have reassembled taking care with the Thackeray gaps. That's as
far as I got today. No time for another test run. We'll see in the morning
if I made any difference.

If not I may be looking for some Houston area twincam/Weber expert if there
is such a thing. I hope I don't have to follow Arno's lead and buy new
Webers!!

Thanks,
Don
"Roger Sieling"
 

PostPost by: Guest » Mon Sep 18, 2000 12:24 pm

Hi
Are you operating the carb. throttles by hand? If so, does the engine
shake about on its mounting as you increase the revs? If you force the
throttles shut by hand after blipping the engine does the engine speed
still not return to its rough idle? If the answer to both these questions
is yes, check the static ignition timing and if this is correct then I
suspect someone has been playing with the idle screws. Unscrew them and
clean the ends, blow out the seats then screw them gently home. Now
unscrew them about one and a quarter turns each and try again.

You may need to unscrew individual screws to get a balanced idle.

Nigel Furness
Guest
 

PostPost by: "Brian Scally" » Mon Sep 18, 2000 1:40 pm

--- In ***@***.***, "Don Fysh" <[email protected]> wrote:
This has not been a good day.

I looked up and saw blue smoke coming from under the dash.

The wiring loom is fried. I'm not sure what caused
it yet. I was recharging the battery at the time (2 amp setting).
Could that do it?

Yes it is possible that the regulator gave up/ got confused and this
happened

<snip>
Bummed,
Yep. You have our deepest sympthese (spel?)


Don

Any way my two cents worth on rewiring.

Check the regulator
Check all the instruments (tacho and voltage regulator are nost
sensitive
If you want to make up a new loom the idear of more fuses is good.
Under the dash I would suggest right angle crimps. They really
improve neatness.
As well as good cable buy GOOD crimp connectors and a propper crimp
tool.
Don't fart about with pre-insulated connectors. Crimp - solder -
clean the flux and then put the insulation over. DON'T LET THE
SOLDER WICK UP THE CABLE
Don't touch the stripped end of the wire before crimping

Unlike others here I would say that bullets are OK. any connector
that can last 30 years in a car environment and is that cheap is
excellent. Just be aware that once disturbed you may have all kinds
of problems.


Brian
"Brian Scally"
 

PostPost by: gobw2 » Tue Sep 19, 2000 1:44 am

Don - Orig wiring on my Elan was plastic insulation with color stripes in
it. looks similar to low grade TW commercial electrical wire common in
the late 1950's & early 60's. Heat causes the plasticizers to evaporate,
leaving behind hard, brittle plastic which cracks when flexed. This
wire, as well as wire I have seen in replacement looms is not very
tolerant of oil or other vehicle fluids, that is why I suggested MTW.
creating parallel circuits as the author of the wiring article suggests
is a serious violation of the national electric code, and would be
frowned upon by people in the profession. the only exception is
grounding . The code certainly does not have to be followed in an
automobile, but the practices, procedures and methods are designed to
maximize reliability, safety and trouble shooting in any electrical
system. George.

On Sun, 17 Sep 2000 21:21:43 -0400 Donald Lee Butler <***@***.***>
writes:
-------------------------- eGroups Sponsor

Don,
The problem probably is the rubber insulation used on British cars.
The rubber rots and the wires sooner or later touch. My ?lan had the
same problem as yours but before it was 10 years old!
I once read about a MGB that the starter turned on while parked and
didn't stop until the battery was disconnected. The writer's comment
was to never leave the car in gear when up on jack stands because
just
five minutes before the starter went crazy he was under it.
I found a site that deals with British wiring, some of the tips may
help you install the new harness.

http://ourworld.compuserve.com/homepage ... iring.html

Don Butler
45/9469


Don Fysh wrote:
>
> . . . I looked up and saw blue smoke coming from under the dash.
>
> Panic time!!! Grabbed the fire extinguisher, turned off the
ignition,
> quickly disconnected the battery. Smoke abated. Fortunately
didn't need
> the extinguisher!!
>
> Looked under the dash. The wiring loom is fried. I'm not sure
what caused
> it yet. I was recharging the battery at the time (2 amp setting).
Could
> that do it? I also had a dwell/tachometer connected.
>
> Bummed,
> Don


The Lotus Elan mailing list is provided by the LotusElan.net
website.


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Posts: 968
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PostPost by: "A.B. Sta. Maria&quo » Tue Sep 19, 2000 5:20 am

George,

What are "parallel circuits"?

creating parallel circuits as the author of the wiring article suggests
is a serious violation of the national electric code ....

Andres
45/8439
"A.B. Sta. Maria&quo
 

PostPost by: "Roger Sieling" » Tue Sep 19, 2000 12:01 pm

George,

The wire in Lucas wiring looms is bad, huh. When I restored my 1958 Lotus Eleven, I was surprised to find there was PVC covered wire in the original harness, compared to what I was used to seeing during this period of Englishautomotive history, which was commonly cloth insulated wire in a cloth loom. The exterior taping was deterorating badly but the actual wire insulation was still in remarkable shape. So, about a foot at a time, I stripped thetape, cleaned and visually inspected the harness, checked continuity and retaped the exterior. It has now functioned quite well in a vintage race environment for the last 12 years. As I restore my 20/22, I am considering using wire salvaged from an old MGB loom to keep the color codes I instantly know from years of experience. What would you fuse on a race car?

Roger

>> ***@***.*** 09/18/00 09:42PM >>>

Don - Orig wiring on my Elan was plastic insulation with color stripes in
it. looks similar to low grade TW commercial electrical wire common in
the late 1950's & early 60's. Heat causes the plasticizers to evaporate,
leaving behind hard, brittle plastic which cracks when flexed. This
wire, as well as wire I have seen in replacement looms is not very
tolerant of oil or other vehicle fluids, that is why I suggested MTW.
creating parallel circuits as the author of the wiring article suggests
is a serious violation of the national electric code, and would be
frowned upon by people in the profession. the only exception is
grounding . The code certainly does not have to be followed in an
automobile, but the practices, procedures and methods are designed to
maximize reliability, safety and trouble shooting in any electrical
system. George.

On Sun, 17 Sep 2000 21:21:43 -0400 Donald Lee Butler <***@***.***>
writes:
-------------------------- eGroups Sponsor

Don,
The problem probably is the rubber insulation used on British cars.
The rubber rots and the wires sooner or later touch. My ?lan had the
same problem as yours but before it was 10 years old!
I once read about a MGB that the starter turned on while parked and
didn't stop until the battery was disconnected. The writer's comment
was to never leave the car in gear when up on jack stands because
just
five minutes before the starter went crazy he was under it.
I found a site that deals with British wiring, some of the tips may
help you install the new harness.

http://ourworld.compuserve.com/homepage ... iring.html

Don Butler
45/9469


Don Fysh wrote:
>
> . . . I looked up and saw blue smoke coming from under the dash.
>
> Panic time!!! Grabbed the fire extinguisher, turned off the
ignition,
> quickly disconnected the battery. Smoke abated. Fortunately
didn't need
> the extinguisher!!
>
> Looked under the dash. The wiring loom is fried. I'm not sure
what caused
> it yet. I was recharging the battery at the time (2 amp setting).
Could
> that do it? I also had a dwell/tachometer connected.
>
> Bummed,
> Don


The Lotus Elan mailing list is provided by the LotusElan.net
website.


"Roger Sieling"
 

PostPost by: Donald Lee Butler » Tue Sep 19, 2000 1:34 pm

George and All,
As my wiring harness was changed (along with the fascia and cowl fiberglass)
before I bought the car I assumed the author of the article was correct about
the rubber. I've seen an original wire harness from an MG-TC (1947 vintage)
and it did look like rubber. Either way, a warning to all who have an original
wiring harness: Some day, sooner or later, it will fry!

Don Butler
454/9469


***@***.***e:

Don - Orig wiring on my Elan was plastic insulation with color stripes in
it. . . .
George.

Donald Lee Butler
 
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