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how long do you let your fiero warm up in the cold by fierobrian
Started on: 01-10-2004 03:45 AM
Replies: 40
Last post by: Rainman on 01-16-2004 10:17 AM
fierobrian
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Report this Post01-10-2004 03:45 AM Click Here to See the Profile for fierobrianSend a Private Message to fierobrianDirect Link to This Post
i was just thinking about how long do you let your fiero warm up on the cold days.I let my 86 se v-6 warm up for about 3-5 min depends how cold.JUST WANT TO SEE WHAT OTHER PEAPLE DO
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Report this Post01-10-2004 03:55 AM Click Here to See the Profile for GTDudeDirect Link to This Post
Well, it NEVER, EVER gets as cold here as it does there, but I usually wait at least until the starter has stopped spinning..............LOL......seriously. DO AS I SAY...NOT AS I DO!

Phil

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Report this Post01-10-2004 03:56 AM Click Here to See the Profile for FierobsessedSend a Private Message to FierobsessedDirect Link to This Post
I let it warm up till the guage moves, usually about 10 minutes, or until the idle comes down
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Report this Post01-10-2004 06:56 AM Click Here to See the Profile for Old LarSend a Private Message to Old LarDirect Link to This Post
When I lived in the cold climate, I let the car warm up for maybe a minute, or until I cleared off all the snow and thawed out the windows.
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Report this Post01-10-2004 07:31 AM Click Here to See the Profile for 2farnorthSend a Private Message to 2farnorthDirect Link to This Post
Depends on how cold. It's -26 on thermometer here this morning, so I'd warm up any car for about 10 min before trying to move it. At +10 I'd only do about 5 min.

Dave

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Report this Post01-10-2004 12:08 PM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreDirect Link to This Post
I use Mobil 1 and don't worry about warm up. Warming up just wastes fuel. Fuel is too bloody expensive to waste. I just keep my gloves on the first mile or three untill the interior warms a bit. If it wants to run rough at the first traffic light, which is only a half mile, I just knock it out of gear until the light changes.

If it snows, or especially if there is ice on the car... Then I do let it warm... That releases the ice without scraping what can damage the glass.

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Report this Post01-10-2004 12:12 PM Click Here to See the Profile for ElectrathonClick Here to visit Electrathon's HomePageSend a Private Message to ElectrathonDirect Link to This Post
Letting a cold car sit running to warm it up is very hard on the car, but I do agree it is nicer to start out the drive in a warm car. I am a machanic and I personally only let it run as I am scraping the ice off.

I am in Oregon now but grew up in Alaska, the usual recomendation was to let it warm up no more than a couple minutes, but always long enough for the oil preasure to build (the oil preasure thing may sound strange but when it is really cold it can take a little while to build oil preasure).

When you first start out just drive it gently for a few miles.

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Report this Post01-10-2004 12:33 PM Click Here to See the Profile for jscott1Send a Private Message to jscott1Direct Link to This Post
 
quote
Originally posted by Electrathon:

Letting a cold car sit running to warm it up is very hard on the car, but I do agree it is nicer to start out the drive in a warm car. I am a machanic and I personally only let it run as I am scraping the ice off.

Back when I lived in a cold climate this was my opinion. I only let it warm up if I had to clear snow off it, otherwise I got in and drove immediately.

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Report this Post01-10-2004 12:46 PM Click Here to See the Profile for TugboatSend a Private Message to TugboatDirect Link to This Post
As long as you're not doing holeshots out of your driveway, it shouldn't make too much difference. Just take it easy until it warms up. Revving an engine too much with cold oil is hard on the pump drive. I used to know a guy with a Honda 600 that his wife and daughter would rev cold and it would eat the teeth off the pump drive gear.

GL

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Report this Post01-10-2004 01:02 PM Click Here to See the Profile for GARY TUCKERSend a Private Message to GARY TUCKERDirect Link to This Post
90% of engine wear occurs within two minutes of cold engine start-up....hot or cold weather...have you ever seen an an enlarged view of piston and ring angle differences when hot and cold? I think if you had you would at least warm up for a few minutes in the popper way...SORRY IF THIS SOUNDS OFFENSIVE! but it is true!

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scrabblegod
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Report this Post01-10-2004 02:01 PM Click Here to See the Profile for scrabblegodSend a Private Message to scrabblegodDirect Link to This Post
I let mine warm up for 10 min when it is below 20 degrees.
3 days ago, My wife got in my car and took off for work. I was sitting in her car with the window iced up.
She pulled out of the driveway and nailed it. As she went down the road, I see a trail of oil behind the car. I take off after her in hers with my head out the window so I can see where I am going. By the time I catch her, she has made it the 6 miles to work.
It seems the high pressure (pegs both gauges at 80psi) from the cold oil blew one of the oil lines off the cooler. There was no oil in the engine so I ran to the store and got 5 quarts. I poured it in and started the car. All of the lifters where collapsed and it took about 2 min before all the clicking was gone. I should add that my wife is deaf, so she never heard the noise (she is also unobservant of the gauges). Drove it and it still has good pressure and no noise. I guess I am lucky there because I have only had the engine in the car for 2 1/2 months and will not have the new engine built for a couple more months.

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Report this Post01-10-2004 02:44 PM Click Here to See the Profile for rogergarrisonSend a Private Message to rogergarrisonDirect Link to This Post
1 minute at the most. They warm up a LOT faster driving than sitting. Hasnt caused me any problems. All my cars have well over 100 K.
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Report this Post01-10-2004 03:42 PM Click Here to See the Profile for ED's85GTSend a Private Message to ED's85GTDirect Link to This Post
3 to 5 minutes. I have never liked to 'start and go" i believe that it is rough on motors.

Ed

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Report this Post01-10-2004 06:22 PM Click Here to See the Profile for ryan.hessSend a Private Message to ryan.hessDirect Link to This Post
 
quote
Originally posted by ED's85GT:
3 to 5 minutes. I have never liked to 'start and go" i believe that it is rough on motors.
Ed

I think so too... I think cold engines have larger clearances (pistons, bearings), and is why most knock a little if it's really cold. That's why I don't want to stress the engine if it's really cold out.

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Report this Post01-10-2004 06:36 PM Click Here to See the Profile for TryxalonClick Here to visit Tryxalon's HomePageSend a Private Message to TryxalonDirect Link to This Post

10 minutes seems excessive.

"long enough to clear the snow"?? I would think this would be right. Somewhere between 30 seconds and 3 minutes. Just enough time to make sure everything is operating properly -- just like in warm weather.

It seems to me that "Idle" is the least correct of all engine operations: running, but not 'working'. Of course, until the engine reaches normal operating temperature, I 'take it easy' ... smooth shifts, graded speed transients, trying to take care of the car and make sure it is running as it should be ...

But I do that ALL the time.


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Report this Post01-10-2004 06:55 PM Click Here to See the Profile for jstrickerSend a Private Message to jstrickerDirect Link to This Post
Let it warm up until it idles smoothly and you know the fluids have all gotten circulated well, then drive easily until the temp gauge starts to move. Any more than that in a gasoline powered vehicle is just wasting gas if the temps are above about 15°F or so. If it's colder than that, I let it warm up for a minute or so, then treat it gently until I see the temp start to come up. You might as well be driving slowly and getting SOME miles per gallon as letting it sit and idle and getting 0 miles per gallon.

John Stricker

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Report this Post01-10-2004 07:00 PM Click Here to See the Profile for Hairy_FieroSend a Private Message to Hairy_FieroDirect Link to This Post
.

[This message has been edited by Hairy_Fiero (edited 05-12-2004).]

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Report this Post01-10-2004 07:06 PM Click Here to See the Profile for MastermindSend a Private Message to MastermindDirect Link to This Post
 
quote
Originally posted by Electrathon:

Letting a cold car sit running to warm it up is very hard on the car.

This seems like a contradiction. Would you and all that agree please tell us why you believe letting a car warm up is worse than driving off right away?

BTW I'm talking about cold winter weather.

[This message has been edited by Mastermind (edited 01-10-2004).]

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Phil86SE
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Report this Post01-10-2004 07:40 PM Click Here to See the Profile for Phil86SESend a Private Message to Phil86SEDirect Link to This Post
 
quote
Originally posted by Old Lar:

When I lived in the cold climate, I let the car warm up for maybe a minute, or until I cleared off all the snow and thawed out the windows.


Ditto!

I do that every morning

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Report this Post01-10-2004 07:48 PM Click Here to See the Profile for jstrickerSend a Private Message to jstrickerDirect Link to This Post
I don't advocate long warm ups as I think they do nothing but waste gas. But that doesn't mean I just hop in the car and go blasting off when it's below zero out.

An engine's clearances change with temperature. The more out of the normal range the temperature is, the more the clearances change. Additionally, in spite of multi viscosity oil, oil is very stuff when you're talking about well below freezing temperatures. If you rev the engine too much, you're really loading your oil pump and system. In very cold weather, I've seen oil filters burst and oil pump drive shafts shear off because of high rpm operation immediately on start up. I even saw a hydraulic pump housing rupture one time on a cold morning. The relief valve in the pump can be inadequate in very cold temperatures to control over pressure.

The engine also relies to a smaller extent on oil splashed onto the cylinder walls and piston pin area. When an engine is first started, that oil isn't there in normal quantities and when it's colder it takes a bit longer for them to get lubricated. Oil is sent to the top end through a variety of means on different engines but on GM engines that's typically through the push rods. Those openings aren't very large and cold, heavy oil doesn't get to the top end as quickly as it normally will.

FWIW, I warm my engines pretty much the same in the summer or winter unless it's VERY cold (below about 15). I start them, let them idle until the idle smoothly, then drive them gently until the temp gauge starts to move. By the time the water temp is high enough to start moving the gauge, the internal components are getting pretty close to normal operating temperature.

John Stricker

 
quote
Originally posted by Mastermind:

This seems like a contradiction. Would you and all that agree please tell us why you believe letting a car warm up is worse than driving off right away?

BTW I'm talking about cold winter weather.

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Report this Post01-10-2004 10:34 PM Click Here to See the Profile for silver86seSend a Private Message to silver86seDirect Link to This Post
hi i wait til the guage moves to "c" and then move the vehicle, also you need some heat to defrost windows, how can you see where your going..
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Report this Post01-10-2004 10:43 PM Click Here to See the Profile for TaurusThugSend a Private Message to TaurusThugDirect Link to This Post
i turn the car on and when it stops then extremes in idel 2k then 500 then i drive off unless im REALLY in dire need to get to school then i start it and when i can keep the car on and in gear i start driving

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Report this Post01-10-2004 10:50 PM Click Here to See the Profile for LandoSend a Private Message to LandoDirect Link to This Post
It's beginning to get cold here in the Midwest, thus I will let it warm up enough to give the fluids enough time to circulate and get warm...that takes about 5min or so. Most of the time I'll wait until I get some form of heat out of the heater or until my teeth stop chattering . Pontiacs have great heaters!
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Report this Post01-10-2004 10:57 PM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreDirect Link to This Post
Mobil 1's pour point is below even Exxon Mobil's own crude based oils. Pour Point is tied directly to how fast oil pumps up in cold weather. Mobil 1 is in the first column and Exxon Superflo in all others. This data is directly from Exxon Mobil and is tested to industry standards.

Don't get me wrong... the oil is getting heavy above it's pour pount. It's just that oil with a lower pour point is thinner at that same temperature.

This table also shows why you don't want 20W-50 in cold weather... All those numbers should scare you.

code:
Typical Properties 
Mobil 1 Superflo-->
SAE Grade 5W-30 5W-20 5W-30 10W-30 10W-40 20W-50
Viscosity, ASTM D 445
cSt @ 40º C 56 47 62 70 96 172
cSt @ 100º C 10 8.3 10.4 10.4 14.1 19.0
Pour Point, ºC -45 -30 -30 -33 -33 -21

Exxon Superflo
Mobil 1 5W-30

If you don't see full oil pressure within a couple seconds of starting or the pressure peaks way above range... you've got problems beyond oil viscosity. I've tried to explain that before but people just don't seem to get it. Very low and very high oil pressure is NOT normal under any conditions.

[This message has been edited by theogre (edited 01-10-2004).]

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Report this Post01-10-2004 11:50 PM Click Here to See the Profile for ditchSend a Private Message to ditchDirect Link to This Post
 
quote
Originally posted by Electrathon:

Letting a cold car sit running to warm it up is very hard on the car,

When you first start out just drive it gently for a few miles.



This struck me as odd. Why would driving off on a cold engine be better than letting the fluids get going a bit and then driving off?

I think that after sitting all night, pretty much all of the oil in my car has settled to the oil pan. I would think you should start it up and let the oil get thru the system a minute (under no load) instead driving away and putting a load on everything before it's well lubricated.

Dave


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Report this Post01-11-2004 12:09 AM Click Here to See the Profile for 2000RagTopSend a Private Message to 2000RagTopDirect Link to This Post
Any vehicle I drive in the winter, I allow to warm up for just a min or two. Then I drive slow till the engine warms up completely.

Now , The biggie, that most people forget about is the rest of the drive train. That has to warm up also before exerting a little
HP on it.

In the summer time when I drive my Vette, it takes a good 5-6 miles of driving before the transmission/differential are warmed up
I’m able to get a digital temp reading on my tranny/differential. I’m really amazed at how long it takes for this to warm up.

I can only imagine how long it would take if it were 0 degree out…………….”let your drive train warm up also”

-Michael

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Report this Post01-11-2004 12:22 AM Click Here to See the Profile for Fastback 86Send a Private Message to Fastback 86Direct Link to This Post
Well, it doesn't get far below 32* F very often in the winter, or any other time, so its not a huge problem.

Quite simply, I'm always running late unless its something really important, so I usually just start it and it warms up for however long it takes for me to clear the windows and put the face on the cd player and put it in gear. Then I go.

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Report this Post01-11-2004 12:25 AM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreDirect Link to This Post
again... It should only take a second or two for the engine to reach full oil pressure. Unless the engine has sat for days to weeks, there is enough oil film on most parts to be fine for that length of time. Unless there is a problem with the oil pump, the engine is building oil pressure while cranking even before it starts. Even that small amount of pressure helps charge the system for once the engine starts.

Lifters that are working right will pump up within a couple engine rotations after recieving oil pressure. (Doesn't even have to be full pressure.)

Oil won't completely drain from an engine for quite some time if at all. All OE for oil filters for Fiero have anti drain valves in them. It is nearly imposible to drain a mounted filter. It's not so easy to drain them off the engine without punching a hole in the can.

Unless it is below 0F I wouldn't warm up any vehicle for long. Not more than a few minutes even then. (I used to live in Upstate NY. I do know cold.) As noted, I run Mobil 1 so I worry about it even less than I would with crude based oil.

The only time I leave a vehicle run longer is when it is covered in heavy ice. It is better to get some heat in the glass than to fight with a scraper/claw to get thru it. Safer too... I've seen windows break more than once from that. Scraping ice can generate way more stress on a panel than people think. Once you get the glass started heating the ice will release from the bottom and you can push the whole mess off. sometimes you can push it off as a single sheet if you can get it cracked at the edges.

Coolant is a non issue. If the coolant isn't moving instantly then it's frozen and you have way worse problems to deal with.

Unless you have an old engine... the ECM knows what the coolant temp is and runs the engine accordingly. Many newer cars also know the oil temp of both the engine and transmission as well. If you are having problems running an EFI motor in cold weather something is wrong with it.

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Report this Post01-11-2004 12:32 AM Click Here to See the Profile for 2000RagTopSend a Private Message to 2000RagTopDirect Link to This Post
Any vehicle, it doesn't matter if it's winter or summer "Let your tranny/differential warm up!!!"

-Michael

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Report this Post01-11-2004 08:52 AM Click Here to See the Profile for LS1swapClick Here to visit LS1swap's HomePageSend a Private Message to LS1swapDirect Link to This Post
I don't drive my Fiero in the winter any way, but in my daily driver I let it warm up about five to ten. It takes that long for the windows to clear regardless. Plus it is nice to go to work in a warm vehicle rather than a cold one. I have even thought of putting in a remote starter. I do run mobile one in it too. Even on a new car you will hear the lifters rattle ,and knock for a few seconds with regular oil. I don't think it uses that much gas for the 5-10 minutes of idling. If you really want to do it right get a block heater. I have one on my diesel. Instant heat right from start up
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Report this Post01-11-2004 09:17 AM Click Here to See the Profile for SilverStarFieroSend a Private Message to SilverStarFieroDirect Link to This Post
I wish I had a block heater. It's COLD up here.

I've gotta let it heat up for about 5 minutes before I'll drive it in the winter.

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Report this Post01-11-2004 10:18 AM Click Here to See the Profile for ManiMackSend a Private Message to ManiMackDirect Link to This Post
I was -20 here the other day! I would never just jump in my Fiero and drive.

It was difficult to get the car started, my ignition lock was so cold (with the rest of my car) that it was hard to turn the key!

So yeah I run my car about 3-4 mins before I drive it, its nice and warm by that time and its out of Cold Idle mode.

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Report this Post01-11-2004 02:43 PM Click Here to See the Profile for rogergarrisonSend a Private Message to rogergarrisonDirect Link to This Post
Soon as you have oil pressure, its safe enough to go. Theres also sort of a fail safe built in. Try to floor a very cold engine and it wont go anyway. you will just get coughs and sputters until it warm enough to accept it.
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Report this Post01-12-2004 11:09 PM Click Here to See the Profile for iluvmacsClick Here to visit iluvmacs's HomePageSend a Private Message to iluvmacsDirect Link to This Post
It seems that although all of us have a very fuel inefficient car, we're all concerned about wasting gas by letting the car idle for a few minutes. A properly operating engine uses very little gas at idle, and more than 80% of the gas combustion energy is devoted to heating the block (or radiator, depending on how long it takes the metal to warm up).

My point, only that if you're concerned about gas, drive a more efficient car, and that if you want to prevent damage, give the engine a minute to transfer some heat to the oil.

If the temp gauge moves before you drive, you wasted time and fuel, because by the time the coolant reaches operating temp, everything metal up to an inch outside the cylinder is at operating temperature.

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Report this Post01-13-2004 08:44 AM Click Here to See the Profile for dguySend a Private Message to dguyDirect Link to This Post
 
quote
Originally posted by fierobrian:

i was just thinking about how long do you let your fiero warm up on the cold days.I let my 86 se v-6 warm up for about 3-5 min depends how cold.JUST WANT TO SEE WHAT OTHER PEAPLE DO

Well my answer may not count 'cause only my wife's Fiero stays out in the winter (i.e. it's hers I'm driving, not mine ), but how long we let any of our vehicles warm up when it's cold out depends upon how cold "cold" is. Seriously.

I'll wait until the defroster is able to keep at minimum the bottom half of the windshield clear before leaving the driveway. Under most circumstances I have... reservations about not being able to see where I'm going.

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-d.

1985 2M6 SE, poly'd and Koni'd (his)
1984 2M4 all stock... so far (hers)

[This message has been edited by dguy (edited 01-13-2004).]

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Report this Post01-15-2004 11:51 PM Click Here to See the Profile for Jeff of NCSend a Private Message to Jeff of NCDirect Link to This Post
I'm with the orge on this one. When a car is at idle the pump is not putting out as much volume. so it is hard on an engine to idle when warm or cold as far as letting the drive train warm up how is it doing to warm up when the car is not moving? Just start it check oil pressure, and drive easly for a few miles.
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jstricker
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Report this Post01-16-2004 12:32 AM Click Here to See the Profile for jstrickerSend a Private Message to jstrickerDirect Link to This Post
Regardless of how inefficient the car/engine is, it's doing better than when it's sitting and idling. At that time, it's getting 0 mpg. It can't get any worse than that.

John Stricker

 
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Originally posted by iluvmacs:

It seems that although all of us have a very fuel inefficient car, we're all concerned about wasting gas by letting the car idle for a few minutes. A properly operating engine uses very little gas at idle, and more than 80% of the gas combustion energy is devoted to heating the block (or radiator, depending on how long it takes the metal to warm up).

My point, only that if you're concerned about gas, drive a more efficient car, and that if you want to prevent damage, give the engine a minute to transfer some heat to the oil.

If the temp gauge moves before you drive, you wasted time and fuel, because by the time the coolant reaches operating temp, everything metal up to an inch outside the cylinder is at operating temperature.

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Report this Post01-16-2004 12:48 AM Click Here to See the Profile for jstrickerSend a Private Message to jstrickerDirect Link to This Post

jstricker

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I didn't read in Ogre's posts that he said that at all.

The oil pump in any engine we have in a Fiero (even swaps) is a positive displacement pump. It will put out exactly the same amount of oil VOLUME at a given rpm if the oil is hot or cold. What will change is the pressure and that will vary for any given engine with the true viscosity of the oil being pumped. Some engines with a lot of tight clearances will have very high oil pressure, some that are older or just looser will have less pressure.

There are three things that determine what your oil pressure is. First, it's pump capacity vs. bypass. The initial bybass is your clearances in your bearings (rod, mains, cam). After that it's the amount of controlled leakage of oil that gets sent to the top end which, in a 2.8, is 12 fixed orifices in the pushrods and leakage past the lifters. The second thing is the viscosity of the fluid (in this case oil) that's being pumped. Since the pressure is determined by how fast things "leak by", the thicker the fluid the less can "leak' in any given time period. The third is the bypass, or relief, valve in the oil pump itself. This is set to open and bleed off more pressure after that pressure reaches a certain point.

Regardless of pressure, if there is sufficient oil to immerse the pickup, the pump will be moving the same amount of oil, of all intents and purposes. That's why you can see a pressure increase with a high volume pump, it is pumping more oil but the leakage rate past the bearings and other controlled leaks is the same at a given pressure. To push more fluid out of a fixed hole, you have to increase the pressure.

When you think this all through, it isn't any "harder" on an engine to idle it than it is to drive it UNLESS you have an oil system problem to begin with in the form of a weak pump or excessive bearing clearances. In THAT situation, you may not be able to maintain enough pressure to properly lubricate all the parts.

When it does get very cold, though, you have this positive displacement pump that is now going to build more pressure because not as much oil is going to get pushed by the bearings due to higher viscosity. In that case, if you rev the engine up excessively you will open the relief valve. If the viscosity is high enough that the bypass can't bleed sufficient oil out to lower the pressure to a safe level, then you run the risk of shearing a pump shaft (since power required to drive the pump is directly proportional to the pressure developed), blowing a filter cannister, or finding another weak link in the system.

Personally, I watch the revs pretty closely when the temps get below about 15°F until I'm sure the oil has begun to warm up. Beyond that, it'doesn't do much good to sit and wait on it for very long.

John Stricker

 
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Originally posted by Jeff of NC:

I'm with the orge on this one. When a car is at idle the pump is not putting out as much volume. so it is hard on an engine to idle when warm or cold as far as letting the drive train warm up how is it doing to warm up when the car is not moving? Just start it check oil pressure, and drive easly for a few miles.

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Pyrthian
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Report this Post01-16-2004 08:18 AM Click Here to See the Profile for PyrthianSend a Private Message to PyrthianDirect Link to This Post
My Fiero I let warm up until the idle kicks down - cant wait to drive it much more than that....
I had a VW Rabbit Diesel way back, and that thing got me in the habit of looong warm-ups. But, right now, I drive my Suburban thru the winters, and I let it sit & warmup at least 5 mins. If I can, I'll let it sit & warm up to the point it melts the windshield ice. Fortunatly it warms-up quick, and will melt the windshield ice between 5-10 mins.
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Report this Post01-16-2004 08:21 AM Click Here to See the Profile for TugboatSend a Private Message to TugboatDirect Link to This Post
Also, there's almost no strain on an engine at idle.

GL

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