912 speedometer cable
(July 2012 Pano): How do you replace the speedometer
cable in a 912?
David Seeland: If you are lucky, just the core of
your speedometer cable is broken and you can just replace the core.
Check for a broken core by attempting to pull it out at the
speedometer end. If it is broken pull the other end out at the
speedometer drive at the front of the transmission. Insert the
new core from the rear, reconnect and you are probably done.
If you need to replace the whole cable, access to the inside of the
tunnel is needed: remove seats, rear tunnel cover, gearshift,
handbrake but not handbrake cables, and front tunnel cover.
Open the clips holding the cable in the tunnel at the brake and
shifter holes. Remove the grommet where the cable enters the
interior from the trunk and pull the cable out of the hole at the
rear of the tunnel. Put the boot from the rear of the tunnel
onto the new cable from the speedometer end of the cable, then
insert the cable at the rear of the tunnel after taping the knurled
knob used at the back of the speedometer to the end of the cable.
Route through the metal clips and bend them back down. Be
careful so that the speedometer cable doesn't interfere with the
shift rod or clutch cable in the tunnel. Don't kink the cable
while installing. Reinstall all the stuff you removed.
While you are there check the white nylon bushings on the shifter
and shift rod.
912 battery problem (April 2012
Pano): I have a '66 912.
The battery does not get recharged when driving. The car will
run once jump started by rolling forward and popping the clutch.
However, after it is shut off, there is not enough juice in the
battery to start it. I have purchased several voltage
regulators and replaced them. I have also checked the
generator and the brushes seem to be OK. I have purchased a
second ignition switch and that does not change the problem. I
checked the fuses and cleaned all of the corrosion seen. I
have also replaced the starter motor and insured all connections
were clean.
David Seeland: It seems that your car either has a
bad battery or a bad generator. If you don't have one,
purchase an accurate digital voltmeter. In addition, I
recommend a digital voltmeter that plugs into the cigarette lighter
that allows you to monitor the charging system as you drive, I
bought mine from GoWesty. They are all precise, reading to
tenths or hundredths of a volt, but not necessarily accurate.
A fully charged 12v battery, that has sat overnight so that the
surface chare has dissipated, should read 12.6 volts. If it
reads 12.0 volts it is only 25 percent charged. Have you tried
to charge your battery with a battery charger? Does your 912
start after charging the battery? If you have been having this
starting problem for a long time, then you car's battery many no
longer be good as they don't like being deeply discharged for long
periods of time. Use a battery terminal cleaner on the
terminals, on the inside of the ground strap terminal, and on the
inside of the positive cable clamp. Charge the battery and
take it to a parts store and they will check it. A 12v
generator should put out nearly 14 volts, read across the battery
terminals, at 2000-3000 rpm. Try applying a little pressure to
the brushes while the engine is running to see if the voltage
increases. If it does, the brushes may be too short and should
be replaced.
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1968 912 fuel pump (October 2011
Pano): I have tried
several over-the-counter electric fuel pumps (bypassed the
mechanical pump) with poor reliability. I drive the car only
on "sunny Sundays" and want to be able to get fuel to the
carburetors without having to crank the engine a long time to
operate the mechanical pump to fill the float bowls sot he engine
will start.
David Seeland: Rather than using the electric pump
full time, use the electric fuel pump to fill the carburetor float
bowls and then run the engine using only the mechanical pump.
Filling empty float bowls will take less than 60 seconds. The
pumps will work fine in series. Place the electrical pump
close to the tank. Pumps are better at pushing rather than
pulling. Zims Autotechnik has a momentary on/off/on switch for
use with an electric pump and also sells a 12v Pierburg low-pressure
pump that does not need a pressure regulator for full time use.
Zims also has a 5-8 PSI 6v pump that will need a pressure regulator
to get the pressure down to 2-3 PSI. I have had, and heard of,
more problems with pressure regulators than with pumps. I
recommend a Holley pressure regulator that is available from
Pegasus. NLA has a 6-12v electric pump. For those
of you with 356s, there are electric pump installations available
online at 356registry.com/techinfo. This website has general
and safety information that will be valuable to 912 owners too.
While you have the fuel system apart it would be a good time to add
a large metal fuel filter available from Zims and others under the
car, particularly if you have a plastic filter after the pump and in
the engine compartment as many cars do.
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1976 912E shocks (September 2011
Pano): My car
has the original Boge shocks and struts. I had the car lowered
by a Porsche mechanic for an occasional autocross. He
explained how he did it with the torsion bars. The ride for
the street has become very stiff, bone jarring in fact.
Do I need new shocks and struts, or do I need to raise the ride
height back up a bit. Right now the distance from the floor to
the lowest part of the car at the front suspension is about three
inches -- right under the gas tank. OR a combination of both?
I also run a 50 series tire instead of the original 65 series.
David Seeland: I think you are right about raising
the height because it appears that your shocks are bottoming out.
Racers use front struts with raised spindles to lower the front
without bottoming out the shocks. To avoid bottoming at the
rear, shorter rear shocks would be necessary. Stiffer torsion
bars both front and rear (22 front and 29 rear) would help stiffen
the suspension and keep the tires flat when autocrossing and
paradoxically make the care more comfortable on the street because
the suspension would bottom less, or not at all. Anti-sway
bars front and rear would also help. Lowering the car by
itself without any other suspension improvements slows the car while
autocrossing (no suspension compliance at all when the shock is
bottomed out) and makes it uncomfortable on the street. If all
these modifications sound expensive, they are, and the least
expensive way to improved autocross times (after improving the
driver) is to get some R-compound tires on a set of extra rims.
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1969 912 cleaning carpet (July
2011 Pano): How do I clean the charcoal/Perlon
carpet in my 912? There are no spots, just embedded soil.
John Paterek: I washed my original 1952
America Roadster wool carpet with cold water Woolite. The
pieces were soaked in it then stretched out to dry in the sun.
The carpet is still in the car 29 years later. I feel it will
remove most of the soil you are concerned about without any harmful
chemicals.
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1969 912 oil consumption
(June 2011 Pano): I have a 912 with 120,000
miles since an engine rebuild at 83,000 by [the late] Harry Pellows.
There is no smoke but the engine either uses or loses one quart
every 100 miles. Factory specifications indicate one quart
every 300 to 400 miles. What do you recommend?
David Seeland: I think Pellow used lots of NPR big bore
kits and those do not last as long as stock Mahle pistons and
cylinders so the NPRs could be worn out. I once had a Corvair
engine in a 23-windo VW bus that suddenly began consuming a quart
every 100 miles and it didn't smoke either. The air cleaner
had slipped partially off while driving around the Four Corners area
on dirt and gravel roads. The carburetor throats were coated
with red dust and the rings and cylinders were worn well beyond
reasonable tolerances in only a week. If the onset of your
problem was sudden then you may have broken rings -- unless you have
spent a week off road with mesh air filters. Before you have
somebody rebuild the engine, have leak down and compression checks
done. Look at the plugs for evidence of oil fouling.
Park on clean concrete or cardboard to check for drips.
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912 oil cooler replacement
(January 2011 Pano): I rebuilt my 912 engine 19
years ago and have been vintage racing the car for some time.
The oil temperature seems too high to me. Do you think one of
the new, probably more efficient, aluminum coolers that replace the
original cooler would help?
David Seeland: Yes, it should cool better than
a stock cooler and be less likely to crack the case because of the
lighter weight. However, if you haven't cleaned the cooler by
removing the fan shroud in 19 years, your engine's present oil
cooler is almost certainly clogged with oily dirt.
Furthermore, the tops of your cylinder barrels probably have enough
dirt to grow carrots (if carrots liked oily dirt). I would
remove the engine, the fan shroud and cylinder sheet metal and
carefully clean the cooler and cylinders and reinstall the sheet
metal. After cleaning, the engine oil temperature should be
substantially lower under similar circumstances. If it still
isn't cool enough, then try the aluminum cooler. Try to
eliminate as may oil leaks as possible, particularly pulley leaks
that spray oil into the engine compartment air. Otherwise the
engine oil temperature will soon be back up again, because the oil
cooler and cylinders will collect more oily dirt. I have a
mild 356 race engine with about 45 hours that had cracks in the
bellows area of the pushrod tubes, so I removed the sheet metal and
heads to replace the tubes. I wouldn't have expected it, but
the cooler on my engine was at least ten percent blocked by dirt
although the cylinders were clean. The engine still ran at
less than 210F under race conditions in 96F ambient conditions, but
it has a fairly large front cooler in addition to the stock cooler.
If 45 hours will partially clog a cooler, think what 1000+ hours
will do. Keep the cooling surfaces clean by minimizing oil
leaks and by cleaning under the engine sheet metal every two or
three years.
TOP
912 engine gasket set (December
2010 Pano): I am about to start putting my
engine together. I have a gasket set that is around 9-10 years
old. Is it wise to use that ld a gasket set or should I
purchase a new one? Are newer gasket sets for the 912 really
new or have they been in the parts distribution system for a short
or long time?
David Seeland: I wouldn't worry
too much about the age of the gasket set because most 356s [912s] on
the road have gaskets that old in them and the gaskets have been
heat cycled many times and still seal just fine. Yours have
led a cool plastic-wrapped existence and should be fine. That
said, buying new Viton crank and pulley seals would be a good thing
as they are much better than the stock seals. New gasket seals
really do seem to be new as the packaging keeps changing.
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Tire size for 1968 912
(February 2010 Pano): I have found two responses to
tire questions that seem to be contradictory: I think a 195x60 tire
would be closer to a stock 165x15 tire diameter and should feel
better. If you have a 5.5x15 or 6x15 wheels, I recommend
185/70 or 195/65x15 tires. I have 6x15 original Fuchs wheels
(part number is 901.361.012.06) and am thinking about 195/65/15
tires. Should I go with the 60 as the middle number? I
was told by other sources that no modifications to my car (1968 912)
need to be done and that the tires should have no clearance
problems.
David Seeland: I don't know what tire the 195/60
was being compared to. If you want gearing to remain stock,
then tire diameter should be stock, about 25.25 inches. You
might want smaller for more acceleration or you might want larger
for better fuel economy. The other parameter you should
consider is rim width. There is a range of tire widths that
are acceptable for each tire size. Your six-inch wheels are
too wide for 165/80x15 stock tires so you must choose a wider tire
to fit your six-inch rims. I have recommended 195/60 because I
like the improved acceleration and the visual relationship between
the tire and the wheel well on the lowered car. A 50-series
tire on a stock height car looks strange. The tire has to fit
the rear wheel well without rubbing. A 195/65 is closer to
stock diameter and should fit. Spacers and longer studs are
sometimes necessary depending on the wheel offset. Mounting
one tire and trying it on the rear might be wise. Compromises
on size are sometimes necessary if a satisfactory tire is not
available in the size you prefer. The 15-inch tire is not as
widely used as it once was and choices are fewer.
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912 transmission
(October 2003 Pano): Can you tell me which
transmissions were used in a 1969 912? Is it the 901?
David Seeland: A 1969 912 uses a
magnesium-case 902 transaxle, either a four-speed or a five-speed.
A 901 transaxle from a 911 will have the same gear rations and will
fit a 912 without modification. Magnesium-case transaxles have
a bigger pinion bearing than the earlier aluminum case transaxles.
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912/912E Comfort
(July 2006 Pano): I guess I am old school at heart.
For the most part I subscribe to the idea that most of the great
cars were pre 1972 when the smog regulations started in earnest.
Last week I drove a 1976 912E for the first time and was totally
blown away by the difference in comfort level (from my '69).
The cabin feels much more spacious, seating is much lower and the
elbow room with two aboard is much better. Jake Raby calls the
912E the ultimate touring car and now I understand his infatuation.
These cars are no ready to become smog exempt here in California and
seem to be modestly priced. Are maintenance costs any better
or worse than their older brothers when used as a daily driver?
David Seeland: A I have heard of amazing
long-lived 912E engines. They were designed some 20 years
later than the 356 engine of the original 912 and have improvements
in many areas. Full-flow oil filtration is a big improvement
that preserves main and rod bearings. The fuel injection is
very reliable. Hydraulic lifters could easily be installed
without complete engine disassembly to eliminate valve adjustments.
Parts are less expensive and easier to find because it is a VW
engine for the most part.
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Karmann bodied 912
(Pano): On the driver side doorframe is an ID label.
This label is marked "Karmann." What does this mean? Are
any marked "Porsche?" On earlier 912s this plate had chassis
serial number and paint code. On 1969 models only the paint
code appears, why?
David Seeland: Karmann was a German body
manufacturer that Porsche and VW (the Karmann-Ghia) used from time
to time. Karmann [almost] only built non-sunroof coupe bodies
for the 912. The remainder of the 912 coupes, Targas, and
[almost] all sunroof coupes were built by Porsche who by 1965 owned
[the former] Reutter [body factory], the source of the majority of
356 bodies. My guess is that the ID plate did not say Porsche
because that would be unnecessary. In 1969 Karmann was still
providing bodies so I don't know why Karmann wasn't on the ID plate
unless you have only looked at Porsche-built cars and that is not on
the ID plates as I have surmised. I would appreciate a phone
call from anybody that has "Porsche" on a 912 ID plate. [Commencing
with 1969 model year vehicles sold in the USA, the chassis serial
number/VIN was required to be visible under the windshield, lower
corner drivers side.]
TOP
912E Engine Miss (July
2011 Pano): I have replaced the air-flow
meter, manifold intake hoses, the spark plugs and have replaced the
points with electronic ignition. The car still misses at
around 3500 rpm. Could you suggest what I should check next?
David Seeland: There are still some
ignition components that you haven't replaced: ignition cables and
plug ends, coil, rotor, and distributor cap. Check your
battery voltage to be sure the charging system and battery are good.
Check the voltage after letting the car sit overnight. The
reading should be 12.6 volts for a fully charge battery. Try
to determine which cylinder is missing by disconnecting one plug
wire at a time. The miss will disappear when the missing
cylinder is disconnected. I suppose the miss could be a lean
miss and unrelated to spark. Buy another injector and replace
the injector on the cylinder that was found to be the culprit.
If all this fails you might need to take it to a shop that has an
ignition scope, and knows how to use it.
TOP
912E Fuel Injection Hesitations
I've got a problem with my [912E] fuel injection that can't be
so unique or complicated that someone hasn't previously diagnosed
and solved it. I'm experiencing intermittent gas starved
hesitations, bucking, when accelerating (especially through the
gears when reaching about 3200rpm) If I back off it smooths out.
Ed Mayo: A lot of "could be's" on this, the
injection is basically the same as the 914 1.8 series. A good
starting point (pun intended) is to absolutely verify that the
ignition points are correctly gapped and not bouncing due to a weak
spring or improper installation. The ignition points are the trigger
for the injection vs. engine RPM. I have also seen this problem due
to weak spark plugs. These can be difficult to track down, but you
gotta start someplace, do the easy ones first! Chris
Powell: I agree with Ed, and would add that another common
problem is faulty seals on the oil cap. Another easy place to look.
After that, all tune-up specs should be verified, along with fuel
pressure and delivery volume.
TOP
Related and Relevant Topics:
Fuel for 356B
(March 2012 Pano): What type or grade of gasoline
should I use on [a] 1961 356B Super? All gasoline in my state
is mandated to have 10 percent ethanol. What precautions do I
have to take, if any, in terms of the engine performance?
Someone suggested adding tetraethyl lead, but that is no longer
available in this country. Also what should be done about long
term storage of gasoline/ethanol in the tank? What could or
should be done to prevent rust, etc? I am not even sure if the
carburetor parts or others in the fuel system of this old class are
resistant to ethanol.
 David Seeland: I expect you are not going to
use this as a daily driver. I would buy unleaded race gas for any
non-catalyst car that will likely be driven very little. It
costs about twice as much as premium but has no alcohol and does not
go bad as rapidly as ordinary gas. It wouldn't hurt to add
Sta-bil to the gas. Keep the tank full to avoid condensation.
The valve seats are hardened steel so lead is not necessary.
Replace all the cloth-covered rubber fuel line. You don't want
to soak the interior in gas or have an engine fire. New German
hose that looks exactly like the original is still available from
most of the 356 parts suppliers. Don't forget the three-inch
section between the carbs behind the fan shroud.
TOP
Steering Rack
(October 2012 Pano): I'm refreshing a 1971 911T that
sat for 20 years. I notice the steering rack has dirt
accumulated around the areas adjacent to the boots. Should I
inspect this more carefully? Do you recommend that I remove
the unit and check inside the boots? If it is leaking, does
anybody rebuild it? They are about $1000 from Performance
Product, and that's a rebuilt unit. I'd like to keep as many
parts of the car original as possible. It looks like I'm going
to have to replace everything that's rubber.
David Seeland: I'd say all you need to do is remove the
rack and clean it with degreaser. Then remove the spring
clamps and pull back the boots. It will probably still be
clean inside; if so just replace the boots and spring clamps and you
should be good to go. So far I personally have yet to see one
of those racks wear out. Not saying it can't happen, I just
haven't seen one yet. What you more likely do need to replace
is the rubber coupler between the rack and the steering shaft.
Those do wear out.
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Touch up Paint
(December 2012 Pano): I have a signal red 356SC.
It was repainted in '95 to a very high standard. The color
match with the original un-repainted panels is exceptional. I
know there isn't touch up paint available through Porsche for my
car, but was wondering if there is color available that is a close
match to signal. Regardless of how careful I am, I get an
occasional stone chip .
David Seeland: Take a hinge cover to an automotive
paint store and have them match the a pint in acrylic enamel.
It will be very expensive. Red is one of the more expensive
paints ($400/gallon). Get a half pint or whatever minimum they
allow. There are websites that sell paint to code but I think
your car is too nice for an almost match.
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