Proper engine warm-up - Page 2 - 986 Forum

MNBoxster · 01-10-2006, 02:18 PM

Hi,

To be sure, there are advantages to leaving a Manual Car in Gear when Parked... but there are also some disadvantages.

If you park the Car for an extended period, the Clutch/Gearshift Mechanism can sieze. It's usually a lot more work to disengage a stuck Clutch/ Linkage than it is to engage it if it siezes.

Add to this, if parked on the street and left in gear, should someone hit you, even slightly, it can damage the Clutch and/or Linkage even though it may not effect the bodywork too much, especially with Urethane Bumpers.

I am not advocating using either method, because Handbrakes are also notorious for failing, not because cables stretch as had been suggested by some others, but because if the Brakes are HOT (and therefore expanded) when you apply them, as they COOL off, they contract, loosening their grip on the Discs, and can then slip.

For me, parking on the Street, I put the Car in Neutral, set the Handbrake, and turn the Front Wheel into the curb if on level ground or facing downhill. If facing uphill, I turn the Wheels away from the curb. This way, the Drivetrain is protected and the odds of the Car running up the curb are minimal. Hope this helps...

Happy Motoring!... Jim'99

underDAWG · 01-10-2006, 02:58 PM

Quote:

Originally Posted by MNBoxster

If you park the Car for an extended period, the Clutch/Gearshift Mechanism can sieze. It's usually a lot more work to disengage a stuck Clutch/ Linkage than it is to engage it if it siezes.

Hmmm.... I am not sure if you have rebuilt a clutch or manual gear box before. The above does not makes much sense. …..and no punch intended. Sorry.

The clutch (clutch plate) is always engaged either you are in neutral or in gears. The only time the clutch is disengaged is when you depress the clutch pedal. Therefore, this is no chance to increase the seizes that you are talking about.

Quote:

Originally Posted by MNBoxster

Add to this, if parked on the street and left in gear, should someone hit you, even slightly, it can damage the Clutch and/or Linkage even though it may not effect the bodywork too much, especially with Urethane Bumpers.

Have you seen any damage directly resulted from this practice? I would like to know.

Clutch and gearbox are probably the strongest components in a vehicle. They have to be because they have to handle the torque generated by the engine. If another vehicle hits your car hard, the traction of your tires will break before it will damage your tranny. If it indeed damages your tranny, I guess you have more things to worry about than tranny. I hope this will clear up somewhat.

Cheers.

Brucelee · 01-10-2006, 05:15 PM

"With all the well known int shaft issues, maybe RMS and cylinder sleves I just wonder if this is a result of improper warmup"

No, these are design issues well known by Porsche.

01-10-2006, 05:15 PM

it seems that all the post cover the issue, switch on and drive away slowly until warm, by the way this applies to every vehicles.
on switching off i would recommend to leave the car idling a little especially after tracking or hard driving, i had a flood coming from the engine once while tracking because i switch the car off immediatelly, apparently there is an overflow for the coolant and with the pressure it just open and run out, any ideas on this subject?

deliriousga · 01-10-2006, 05:35 PM

Quote:

Originally Posted by underDAWG

The clutch (clutch plate) is always engaged either you are in neutral or in gears. The only time the clutch is disengaged is when you depress the clutch pedal. Therefore, this is no chance to increase the seizes that you are talking about.

I think Jim is talking about the fact that if the car sits for a long period of time (say a couple of weeks or months) it's possible for the gears to fuse if any type of corrosion occurs inside the gear box. The fact that the pressure plate is pushing the gears together in the same spot for a long period of time combined with condensation would give it that chance. I never think about this because I live where we can drive it all year long every day so that's not a problem, but I can see how it could happen if you store it or only drive it occasionally.

Quote:

Originally Posted by olly986

it seems that all the post cover the issue, switch on and drive away slowly until warm, by the way this applies to every vehicles.
on switching off i would recommend to leave the car idling a little especially after tracking or hard driving, i had a flood coming from the engine once while tracking because i switch the car off immediatelly, apparently there is an overflow for the coolant and with the pressure it just open and run out, any ideas on this subject?

Tracking's a different issue. The engine gets so hot you should let it cool down some by idling so all of the fans are still running until the engine gets back down to normal temp. Same thing if you're in the upper end of the temp scale when driving. If the engine is really hot and you just shut down, all of the heat builds up and has nothing pushing it out so you can cause blown hoses, cracked coolant reservoir, etc.

MNBoxster · 01-10-2006, 05:35 PM

Quote:

Originally Posted by underDAWG

Hmmm.... I am not sure if you have rebuilt a clutch or manual gear box before. The above does not makes much sense. …..and no punch intended. Sorry.

The clutch (clutch plate) is always engaged either you are in neutral or in gears. The only time the clutch is disengaged is when you depress the clutch pedal. Therefore, this is no chance to increase the seizes that you are talking about.

Have you seen any damage directly resulted from this practice? I would like to know.

Clutch and gearbox are probably the strongest components in a vehicle. They have to be because they have to handle the torque generated by the engine. If another vehicle hits your car hard, the traction of your tires will break before it will damage your tranny. If it indeed damages your tranny, I guess you have more things to worry about than tranny. I hope this will clear up somewhat.

Cheers.

Uh...

OK... Let's see...I have totally rebuilt and restored numerous of my own Cars - 1963 Jaguar E-Type (Engine and Tranny), 1959 Triumph TR3 (Engine and Tranny), 1962 Volkswagen Beetle, 1966 Mustang Fastback Hi-Per (Engine and Tranny), 1969 Lotus Elan SE Twin Cam (Engine and Tranny), 1970 Lotus Europa Twin Cam Special (Engine and Tranny), 1985 Lotus Turbo Esprit (Engine and Tranny). And these are just my personal Cars. I did all the work except the requisite Machining. And 2 of these Cars went on to become National Concours d' Elegance Winners and have all seen Track Time.

In addition to this, I maintain and run my own Formula Vee Car in SCCA Club Events and have helped Friends rebuild 6 more Lotus Esprits, a 1968 Lotus Elan+2, a '69 Corvette 454, a '70 Buick Gran Sport Stage 1 455, and have built both a Birkin Seven and a Caterham Seven.

4 years ago, just for ********************s and Giggles, I went to school and earned an ASE Automotive Technician Certification. Oh, and somewhat relevant, but perhaps unrelated, I hold an SCCA National Competition License and am a former US Navy Certified Test Pilot. I also have an MS in Materials Science and an BS and an MS in Aeronautical Engineering.

So, perhaps you are correct, I may be a little limited in my knowledge and experience compared to some.

If you leave the Car in Gear, you can quite easily cause damage to the Drivetrain if the Car is struck. You are correct that the Clutch is engaged except for when the Pedal is depressed, but I was referring mostly to the linkage, you simply put greater emphasis on the Clutch which leads me to believe that perhaps it is you who don't fully understand the concepts here...

Happy Motoring!... Jim'99

PS So far as having seen a Rear Impact damage the Drivetrain which was in Gear - YES - A friend's Esprit was bumped rather mildly in a Parking Lot. The sudden jolt to the Drivetrain broke a Tranny Mount and shattered the Pilot Bearing from the Primary Shaft to the Crank. We had to rebuild the Bottom end after pulling the Crank to have the receiver machined and an insert pressed into the Crank to accept a new Pilot Bearing. Cost - $850 Parts and 22 MH Labor, in addition to a new Rear Valence and Paint (which would have been required anyway from the impact)

underDAWG · 01-11-2006, 09:58 AM

If you put it this way, I must admit that I really don’t understand the concept. You win!!! Please forgive me for stepping on your toes. It is totally out of line.

I apologize to everyone that I have misled you. Please do not put in gear when parking because it may break your tranny mount, connecting rod or and transaxle. Along the some logic, it may be wise not to apply hand brake either because it will put extra stress on the bumper when other bumps into you. Ooop, I spoke too much again.

MNBoxster · 01-11-2006, 10:41 AM

Quote:

Originally Posted by underDAWG

If you put it this way, I must admit that I really don’t understand the concept. You win!!! Please forgive me for stepping on your toes. It is totally out of line.

I apologize to everyone that I have misled you. Please do not put in gear when parking because it may break your tranny mount, connecting rod or and transaxle. Along the some logic, it may be wise not to apply hand brake either because it will put extra stress on the bumper when other bumps into you. Ooop, I spoke too much again.

Hi,

You probably would have been safe to simply let it go after the 1st sentence... You might have overlooked my statement that I am not advocating any particular practice, but rather described my own and the reasoning behind it...

Happy Motoring!... Jim'99

rbennett · 01-11-2006, 10:48 AM

Hay, how about those New England Patriots!!

Brucelee · 01-11-2006, 01:21 PM

Quote:

Originally Posted by underDAWG

If you put it this way, I must admit that I really don’t understand the concept. You win!!! Please forgive me for stepping on your toes. It is totally out of line.

I apologize to everyone that I have misled you. Please do not put in gear when parking because it may break your tranny mount, connecting rod or and transaxle. Along the some logic, it may be wise not to apply hand brake either because it will put extra stress on the bumper when other bumps into you. Ooop, I spoke too much again.

There is an old expression worth remembering.

"Sarcasm is cruel wit!"

Lets all just remain calm and friendly!

RandallNeighbour · 01-11-2006, 02:11 PM

You know what I love the most about the back and forth sarcasm and arguing on this particular thread? I'm not in the one causing trouble this time!

BTW - I am a neutral with hand brake guy myself unless I'm on a hill, and I rarely park on hills in Houston, Texas. We do have very steep hills though. They are called overpasses.

Brucelee · 01-11-2006, 03:12 PM

I always get out and place a chock under the right front tire.

bhduxbury · 01-11-2006, 06:03 PM

"chock" . . . lmao!!

rbennett · 01-11-2006, 08:32 PM

Quote:

Originally Posted by Brucelee

I always get out and place a chock under the right front tire.

WTH is a "chock"

trogdor · 01-11-2006, 09:21 PM

Quote:

Originally Posted by MNBoxster

I am not advocating using either method, because Handbrakes are also notorious for failing, not because cables stretch as had been suggested by some others, but because if the Brakes are HOT (and therefore expanded) when you apply them, as they COOL off, they contract, loosening their grip on the Discs, and can then slip.

This is exactly right. I remember a friend in college who would park his car in his mom's driveway (very slight incline) and only use the handbrake. It would hold the car fine for a few hours but more than once we came outside to get in the car and it was sitting in the middle of the road...

Brucelee · 01-12-2006, 07:13 AM

Quote:

Originally Posted by rbennett

WTH is a "chock"

Block or metal wedge!

underDAWG · 01-12-2006, 07:44 AM

Quote:

Originally Posted by Bruce[QUOTE=Brucelee

I always get out and place a chock under the right front tire.

Are you being funny or sarcastic? It is a fine line, you know?

cheers.......

underDAWG · 01-12-2006, 07:47 AM

It is a beautiful day. Let's have some fun.

Quote:

Originally Posted by MNBoxster

You probably would have been safe to simply let it go after the 1st sentence... Jim'99

Man..... You are really in love with yourself, aren’t you? Dr. know-it-all. Ooop, sorry you only have a master degree. Mr., right?

Dr. underDAWG

Biz-z Z · 01-12-2006, 08:03 AM

Been up all night long. Too tired ot read thsi thread or check for speling mistakes. Are we at DEF-CON 2 yet?

(j/k)

MNBoxster · 01-12-2006, 08:10 AM

Quote:

Originally Posted by underDAWG

It is a beautiful day. Let's have some fun.

Man..... You are really in love with yourself, aren’t you? Dr. know-it-all. Ooop, sorry you only have a master degree. Mr., right?

Dr. underDAWG

Well...

Oh Never Mind... waste of Time and Bandwidth... I'm done here...

Happy Motoring!... Jim'99