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Sunday, January 12, 2020

Appendix “L”: Safely Lifting your 993/964 for Servicing and at the side of the road:

Unlike the older 911 pictured here, a 993 or 964 should only be lifted by their jacking points and never by the engine case. Wearing a white dress shirt and dress shoes while working on your car is optional.

Disclaimer: The content of this document applies to the Porsche 993 (911 1995 to1998) I am not a professional automotive technician and some of the opinions expressed in this document are just that, opinions, therefore, please feel free to use this document at your own risk. Lifting a car and working on a car resting on Jack Stands is inherently dangerous, improper suspension of a vehicle can result in damage to the vehicle, injury, or death. Many times a lot can be learned by simply watching qualified professionals work on your 993.

For some, this document seems to be a long tedious read where they may consider skimming over it and focusing on the section covering exactly how to lift a 993. For safety's sake and to potentially avoid damaging your vehicle please read this document in its entirety before lifting your vehicle.  Even experienced automotive professional technicians can benefit from reacquainting themselves with safety procedures from time to time.


Lifting your 993 for Servicing:

Below are instructions on how to lift a 993 onto jack stands based on discussions with a USA Porsche dealer, factory-supplied documents, researching how others lift their cars, and the review of commercial products designed to specifically lift a 964/993. I have also added additional detail from my personal experience from a safety perspective. Lifting a car or placing any part of your body under a lifted vehicle is inherently dangerous and extreme caution should always be observed.
Definitions as applied throughout this document:
Lever Style
Jack Stand
Jacking Pont

Jacking Point: A factory-designated point on the vehicle's underbody from which a car can be lifted or statically suspended safely off its suspension for servicing without damaging the vehicle. Jacking points are designated in the vehicle's owner's manual in most cases.

Tripod/Clevis Pin
Jack Stand
Jack Stand: A non-lifting static stand designed for use on
 Jacking Points and used to
suspend a car off of its suspension for servicing. 

Floor Jack: Sometimes referred to as a Trolley, hydraulic or Service Jack or lifting jack, it is a temporary lifting jack designed to aid in placing a car on Jack Stands by lifting a  vehicle.


Saddle Cup
Saddle Cup: A cup or a flat lifting plate fitted to the end of the lifting arm of a Floor Jack or the top of a jack stand.

I have found the “3 Ton Long Reach Low Profile” steel hydraulic floor jack purchased at Harbor Freight is an ideal fit for our cars due to its ability to be slid under a car with low ground clearance. Low-capacity or lightweight racing jacks can be dangerous for lifting a 993 for general maintenance procedures.

Important Safety Notes read first:
  • Never ever service a vehicle suspended by a floor or other type of lifting jack(s) only
  • When suspending a 993 for servicing ALWAYS use jack stands that are of suitable capacity to suspend the vehicle and have large flat padded Saddle Cups/plates to mate with the jacking points on the 993/964.
  • Some jack stands Saddle Cups have a centering stud that can be lined up with the centering hole in the jacking points on the vehicle adding an additional assurance that the jack stands are positioned correctly. Use these with care as a misaligned centering stud can bend and damage a Jacking point on a 993/964 when lowering the car onto it. This can render the jacking point unusable with certain lift bars described later on in this document.
  • Do not use wooden blocks, cinder blocks, bricks, or any other item not specifically designed to suspend vehicles to suspend a car as these are known to fail precipitously with disastrous results.
  • Do not lift a Porsche 993/964 onto Jack Stands using the engine case, see factory WARNINGS further down in this document. 
  • If jacking points other than the points specified by the factory are used or the sequence of lifting is not followed the car may be damaged and unsafe conditions will result.
  • Always disconnect the battery before lifting the vehicle. I was told by an acquaintance of a situation where his friend was working on the starter with the battery attached and inadvertently triggered the starter driving the car off the jack stands and nearly killing his friend under the car.  
  • Never put your head or any other part of your body under a lifted vehicle.
  • Having a buddy on hand to observe that necessary safety precautions are taken and quickly respond to any safety-related mishaps is always a good idea.
  • Be sure to loosen and gently re-snug fasteners, such as wheel nuts or studs while the car is on the ground as applying high forces to break these free while the car is sitting on jack stands can be very dangerous.
  • Always position the car on good condition, smooth level pavement, set the parking brake, put the car in gear for a manual transmission and park for an automatic, and chock both sides, front and back, of each wheel that will remain on the ground when lifting the vehicle. This is especially critical on front axles remaining on the ground as they are not locked by the parking brake. Also use properly designed wheel chocks as they reduce the chance of inadvertent, unanticipated, and sudden slipping resulting in an unsafe lifting or servicing condition.
  • Always position the length of the floor jack squarely at a 90-degree angle to the car body when lifting so the jack can float on its wheels freely and stay properly aligned with the jacking point on the car as the car is lifted.
  • If the car is to be placed on 4 jack stands adjust the sets of front and rear static jack stands on the left-hand and right-hand side of the car to the same height and the front-to-back stand heights should be set so the vehicle sits as close to level to the ground as possible front-to-back.
  • Be aware that the car and the lifting jack will slightly shift position (roll) as you lift the car. Take this into account when slowly lowering the car onto Jack Stands.  Always check and adjust the exact position of the jack stands just before they come in contact with the Jacking Points and before releasing the vehicle onto them.
Special considerations when lifting a 993 glass-roofed Targa.
Some have suggested twisting forces can damage the roof mechanism on the Targa. For this reason, using lift bars, discussed further down on this page, is especially important. Also using the emergency jack is suspect and so these cars may best not be lifted at the side of the road using the emergency jack. One can consider just having the car flatbed towed to the service garage for tire replacement.

Warning:

Recently there has been a recall of made-in-China lever/geartooth jack stands from Harbor Freight. For me, this calls into question the safety of any jack stand where the height is adjustable via a lever and a gear tooth rack. 

ESCO Jack Stands

This is because most stands sold in retail stores come from China regardless of the brand and may have come from the same source as those purchased from Harbor Freight. For this reason, I strongly recommend using ESCO-style tripod stands that use a clevis pin to lock in the height of the stand. Also, lever/gear tooth rack stands that include a locking pin feature can be used safely. If you choose to use a Lever/gear tooth rack style stand without a pin locking feature use it at its lowest height setting where it has no opportunity to slip and suddenly give way.
Locking Pin Feature


Lifting the front of your 993 and placing it on jack Stands:
To lift the front for either side of the front of the vehicle:

This method is much like how the emergency jack is used on a single jacking point at a time and introduces twisting forces on the body during the lifting process that are relieved once both of the front jacking points are resting on stands. 
  1. Disconnect the car battery so the starter can't accidentally drive the car off the jack stands.
  2. Chock the wheels as discussed above on the opposite side of the vehicle
  3. Raise the car using a floor jack on the rear jack point, just forward of the rear wheel well, on the side of the car, you intend to lift.
  4. Then once the front tire lifts from the ground and there is adequate clearance under the front Jacking Point, just to the rear of the front wheel well, place a jack stand underneath the front jack point and;
  5. Lower that side of the car onto the jack stand very slowly.
  6. Verify that each jack stand's height adjustment is fully locked,  has been pinned into position by the weight of the vehicle, is centered on its jacking point, and is squarely positioned to the ground below and not tilted. If very gently shaken the vehicle should not wobble when fully seated on the stand. If it does move even slightly resolve the issue before servicing the vehicle.

This can be done individually for both sides of the car to get the front end completely lifted onto jack stands. In such cases work slowly and observantly to make sure there isn't any unwanted movement on the previously mounted side of the car on its jack stand when raising or lowering the opposite side of the vehicle. If very gently shaken the vehicle should not wobble while fully seated on the stands. If it does move even slightly resolve the issue before servicing the vehicle.

Rear Lifting Options:

DO NOT DO THIS:
Use the engine case to lift the rear of the vehicle to place it on jack stands. Some do this based on procedures described on p-car.com and Pelican Parts as well as in multiple places on Rennlist and other enthusiast sites. It turns out that this specific method of lifting the rear of the car by the engine case is specifically advised as NOT the proper procedure as stated in the WARNING in the owner's manual:
 

"The car must not under any circumstances be jacked up by the engine, transmission or front/rear axels this can cause serious damage to the engine on the vehicle"

When lifting the rear of the car by the engine case the added force on the engine case and engine mounts are:

    • For the Turbo 620kg or 1,367lbs.
    • For a Normally Aspirated base Carrera  1,288lbs. 
I was shocked at the considerable additional force the engine mounts & case are exposed to when lifting the rear wheels off the ground by the engine case. 

I have in the past used the engine case lifting method for my 1996 C2. I consider myself lucky to not have damaged my car. Deciding to lift the rear of your car in this way falls under the disclaimer of using this method at your own risk and really need not be done or discussed here since there are good alternative methods described below. Officially Porsche states one may only lift the vehicle by the jacking points and in their dealership shops, all 4 jack points are used simultaneously on a lift. 

Recently I had a set of lifting bars fabricated that will mate with the factory jacking points on each side of the car and run the length of the rocker panel. More detail on this approach is described later in this document.

I did quick polling of 993 owners as to how they lift the rear of their cars to put them on jack stands. One of the responses describes how to lift the car using narrow base jack stands in conjunction with a conventional lifting jack on and near the factory-designated rear Jack Points only. 
    • "As you know, the rear jack point is larger than the front so what I have done in the past (before I purchased a Quickjack) was jack around #1 in the pic. Using these jack stands and a hockey puck, I was able to set the car on the jack stands around areas #3 & 4."




DON'T DO THIS:
I also reviewed some videos on Youtube on how to lift our cars onto 4 jack stands front & back. They suggest using a lifting jack on a suspension component and then placing the jack stand under the jacking point. My view is this is problematic as the suspension components are light-alloy metal and seem to me to be nowhere nearly strong enough running the risk of bending or crushing something.


Consider doing this:
I did a little further research and found that there are specialized jack stands and adapters to specifically lift and suspend a 964/993 by the jack points only as specified by the factory. These solutions use only the jacking points meeting the factory requirement. They do however introduce twisting forces on the body much like when using the factory-supplied roadside emergency jack as the car is raised by individual jacking points one at a time. This method seems just fine if your DIY under-car efforts are limited to oil changes and occasional basic wheel-end work. If you decide that you wish to meet the factory-specified letter of the law with minimal investment in equipment lifting your car the below websites outline how to use these products:
Jack Point Stand
Rennstand

With both of the stands above it is important that the jack points on the car are in good shape and not bent. This is not a problem with the rear jacking points on a 993/964 but can be a problem when using the front points if they are bent.

Recently I read that with the Targa version the 993 lifting the car from a sigle point introduces twisting forces that may damage or put the glass roof mechanism out of adjustment. I have been unable to substantiate this however there are lifting options discussed below that do not introduce these forces.

For lifting the rear of the car I also ran across this option that uses the two rear Factory Jacking Points with a crossbar that could be used to place the rear onto jack stands while not twisting the body.

It would require a long-reach low-profile jack and maybe driving the rear wheels up on a ramp so the jack will clear the rear bumper cover. The crossbar chosen would need to span 48.5"(1236mm) on-center to reach both outer Factory rear jack points, P19 in the illustration below, or 40"(1018mm) to reach the rear platform take up position P20 in the illustration below leaving the P19 positions open to place the jack stands. 

After further investigation, it seems that a crossbar wide enough to lift by the P20 points is longer than standard for these things but can be purchased:
T3 Cross Beam Adapter



Using a pair of rocker panel bars to lift each side of the car:

Another approach using a bar with a floor jack is:
LiftBars
LiftBars in Position
They use a different approach using two bars one on each side of the car using the front and rear jacking points together where each bar is set in a pair of axel saddle style stands holding up both sides of the car. When used with Esco-style stands the ESCO jack stand axle-style replacement post is required. The LiftBars solution requires that the jacking points are not damaged or distorted. On our cars, the left front jacking point is a known weakness and is damaged on many cars. Finding someone willing to make the repair can be a challenge as most body shops do not want to do this kind of work.  The replacement front jacking point parts are 964-501-297-00 (left)964-501-298-00 (right) and will need to be welded in. The LiftBars ordering page for 993 bars describes how to check the mounting points on your car.

A front left lift point
collapsed sideways


A DIY lifting bar approach:
I fabricated a homemade version of the LiftBars out of: 
  • (2) 56" long 2"x3" x 1/4" steel square tubing purchased from a local steel supply house or even Amazon and 
  • (4) 5/8"x 3-1/2" socket head capscrew fasteners with 
  • (4) 5/8" Nylon insert Hex lock-nuts and 
  • (24) 5/8" fender washers (large outer diameter).  (5) washers to form along with the cap screw heads each of the four alignment pin /saddle cups to mate with the jack points
    Front left lift point
    after being repaired
    under the car and (1) used under each of the (4) 5/8" nuts.
  • A can of spray paint to paint the bars to avoid surface corrosion from staining your hands when using the bars. 
  • And of course, if you only have two jack stands you will need to buy two more with similar base heights to the ones you already have to lift all four wheels off the ground.
You may not find the socket head cap screws at a local home improvement store but they will have them at a fastener distributor such as Fastenal or even Granger Industrial Supply. Fabricating your own lift bars will save you about $150 over purchasing the commercial product if you send the bars out for machining and $250 if you have access to tools to do your own machining. In any event, the lift bars will be significantly heavier to handle than the commercial product so the choice is yours. 

With my DIY bars, I removed the lifting posts from my standard jack stands.

The car body jack points are captured by the head of the 5/8" socket head capscrews on the bars and the 5/8" nuts on the backside of the lifting bars are captured in the space where the jack stands posts normally fit. By doing this the car is captured by the cap screw head and the jack stand is captured by the nut on the cap screw making for positive connections that can't slip off laterally.

Maintaining the alignment of  the bar to the lifting jack cup:
Drill and tap a hole or make a slot using a nut inside the bar to add a mounting lag bolt and large OD fender washers on the underside of the bar at the point one plans to place the lifting jack. The exact position will be slightly towards the rear of the car and therefore offset to the center point of the bar's downward face. Finding the ideal position for the jack lifting point along the bar may require some experimentation through trial partial lifting of one's car. The addition of the lag bolt and washers captured in the saddle cup act as a safety measure against the bar sliding off the lifting jack's saddle cup during lifting.  



The jack point alignment studs are approximately 49" on center from each other.

If you are going to fabricate your own bars, I would measure one's specific 993's jacking point distance on the specific car to make sure it fits properly or better yet make a slot in the steel stock as I did so the exact jacking point fit can be adjusted. If one wants to get fancy 2"x3" plastic end caps can be purchased on eBay.  Another fabrication alternative is to go with 2"x2"x1/4" square tube stock so the weight of the lifting bars is reduced. I have not experimented with this, all I can tell you is the 2"x3" 1/4" tube stock is really heavy and seems like overkill.

My car is lowered somewhere between USA standard and ROW lowered height and the lift bars just barely clear the rocker panels when used with my low profile floor jack. If your car is set to a very low clearance putting the bars in place will require some adjustments.
This can be addressed by removing some of the washers that form the jacking pads on each end of the bar. Removed washers can be stored under the hex nuts on the underside of the bar. 


While lifting the car observes the jack floating on the floor to follow the bar while lifting as otherwise, the saddle cup can suddenly slip laterally off the bar creating an unsafe condition and damaging your vehicle. 

As with the LiftBar commercial product, if one of your car's jacking points is bent, it needs to be repaired before using the lift bars.

Thank you Rich C4S from Rennlist who suggested this alternative.

Bar end caps.
Distance Between Jacking points on the body 49-1/64" +/- 5/64"


ESCO axel-style post
One of the key features of using lifting bars to lift the vehicle is that unlike using a floor jack on individual factory jacking points, twisting forces are never applied to the body structure to lift the vehicle front & back. A big plus in my opinion for any 993 and potentially avoiding damage to the roof mechanism on a 993 Targa.

A related note is that if one uses side-mounted lift bars to change the oil on a 993 the plastic rocker panel cover needs to be removed before applying the lift bar to gain access to the oil tank.

In Conclusion: 
Taking into account all the options for lifting a 993 the LiftBar approach, or the homegrown version. They seem to be the winner in that they use the factory jacking points, as required in the owner's manual, and unlike when lifting individual points on the car, they do not introduce body twisting forces. This can be especially important in the case of the Targa 993. If you plan to only lift the rear sides of the car to change the oil or service wheel ends occasionally the JackPoint Jack Stands seems to be reasonable if not an optimal solution too.


Lifting your 993 at the side of the road:

The Original Equipment Emergency Jack, the jack that comes with the 993 Carrera

993 Original 
Carrera style Jack
is compact, lightweight, and extremely unsafe to use at the side of the road. 

Swapping it out with a  Turbo 993 or what seems to be an identical 996/986 scissors-style jack with the jacking point centering stud is probably a good idea for emergency use, part Numbers 000.721.711.05 or 996.721.711.00. I have not personally tested these jacks to verify the jack's saddle's stud fits in the hole on a 993 jacking point but I am sure a dealer can answer this question.  They can be purchased new online at Pelican Parts, from the Porsche dealership or used on eBay, or from a Porsche-focused dismantler. 

000.721.711.05 

Turbo Style Jack



An alternative I use is an inexpensive steel scissors jack from Walmart, Amazon, or almost any auto parts store. In this case, one will need to modify the jack by adding a short bolt, nut, and washers forming a stud that interlocks with the hole on the jacking point of a 964/993. Turns out this arrangement works for a 991 as well, go figure?
This modification of a generic scissors jack is very important as it protects the car from slipping off the jack during an emergency jacking event for the following reasons: 
  • Usually, a roadside berm is not flat, smooth, or in some cases even solid.
  • As a car is lifted the jacking point moves laterally. So when fully raised the center point of the jack-to-car interface point is no longer exactly centered over the jack's foot. This creates lateral forces that may cause the car to slip off a jack without an interface stud present.


If you found this page informative return to the main page and bookmark it for future 993-related servicing, repair, and upgrading guidance & information. If it saved you some coin consider a donation through the button on the top left margin of this page.

#Jack #jacking #lifting #stand #chock #safely  

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