How bad is it to redline your engine?

[Bigdon]

Hi. I was wondering how bad it is to redline your engine, and stay in there for about 5 seconds? The only reason I am wondering is that last night me and my friend were driving down the highway, and decided to open up my car. I had hit the redline and believe I stayed there for about 5 seconds. After that the engine sounded like it had something rattling inside of it, and smelled like it was hot. Now today it wont even start. Any help would be appreciated.

[Plasma]

It's definitely not a good thing. You could very well have broken something. When you say it doesnt start, what happens when you turn the key? Does it try to turn over at all? Does it make any noise, do lights come on?

[Bigdon]

It's definitely not a good thing. You could very well have broken something. When you say it doesnt start, what happens when you turn the key? Does it try to turn over at all? Does it make any noise, do lights come on?

When I try to start it the motor wont even tun over. The warning lights for oil pressure, electrical system, hot transmission fluid, and check engine come on. My friends dad thought by listening to it last night (when it was able to turn over) that it might be a timing belt, I might have broken a rod, or warped the engine.

[Plasma]

If the lights come on and it doesnt turn over, (some kind of ticking noise?), a possible quick fix would be to find the starter (under the car somewhere) and whack it a few times with a hammer. That might save you a lot of time and money. Make sure you hit it pretty hard. If that doesnt fix it, did it rattle more when you were accelerating, or was it constant? It doesnt sound like a timing belt, because it would still try to turn over even if that was broken, and the same with all of your other predetermined symptoms

[Wakesetter03]

What year is your car??
Most modern cars have a limiter at the redline which stops the engine from doing damage.
When you don't have a limiter and have it on the redline, it's called valve bouncing. You could have done some serious damage. The timing belt shouldn't be effected by redlining it, it's usually internal damage. Seals, rods, valves, whatever.

Strange that your car wouldn't have a limiter though. I've had mine off the limiter multiple times (it revs fast) and it hasn't done any damage at all.

[Bigdon]

What year is your car??
Most modern cars have a limiter at the redline which stops the engine from doing damage.
When you don't have a limiter and have it on the redline, it's called valve bouncing. You could have done some serious damage. The timing belt shouldn't be effected by redlining it, it's usually internal damage. Seals, rods, valves, whatever.

Strange that your car wouldn't have a limiter though. I've had mine off the limiter multiple times (it revs fast) and it hasn't done any damage at all.

My car is a 2001 Subaru Legacy. It revs up to 8000 rpms, but I only touched a little over 7000 (where the redline starts), and was doing about 115 mph. I know I've done something, but I'm not sure how bad it is. I know I'm probably screwed though. I've only had the car for about a month.

When I went back and checked on it the oil was low, anti freeze was completely empty, and the battery is really carotid.

If the lights come on and it doesnt turn over, (some kind of ticking noise?), a possible quick fix would be to find the starter (under the car somewhere) and whack it a few times with a hammer. That might save you a lot of time and money. Make sure you hit it pretty hard. If that doesnt fix it, did it rattle more when you were accelerating, or was it constant? It doesnt sound like a timing belt, because it would still try to turn over even if that was broken, and the same with all of your other predetermined symptoms

It rattled more when I was accelerating. Its getting towed to my place today sometime, and might get looked at this week. Its a 2001 Subaru Legacy, and the engine is so complicated to look at, I'm not sure where to begin.


-merged double post. -Emerald Dream

[Wakesetter03]

Hmm... An 01 Subaru should definitely have a limiter.
Did you make sure you check your fluids before you redlined it?
I'm presuming you have a 2.5i NA. The thing with boxer engines is, you need to keep the oil level up.
When they get low in oil and you drive it hard (be it corners or just accelerating) the oil surges. It can cause major engine damage and even can cause the motor to seize.

Subaru's are a fantastic car that will run forever, but servicing is absolutely necessary and driving it hard without proper servicing is a recipe for disaster :(

Flat motors (boxers) burn oil, it's a characteristic of the motor. If it was low on oil and youve had a surge, prepare your wallet... :(

As to where to look, look first for oil leaks. If you can't see any seals leaking oil, drain the oil. You'll be able to tell from the oil whether a head gasket went or what.

[esby]

5 seconds is a little long to bash the limiter. But I love watching other people do it haha. Especially if its something like a ported rotor.

[JackOfClubs]

There must have been some deep problem with the engine for it to just pop by doing that. I've run my car low enough on oil (granted its a straight-4 Honda, but still) that it entered limp mode. However before that I still revved the piss out of it on an almost daily basis, with no issue. It has 233,000 miles on it, and engine wise is near perfect; I near redline it every day. It should take a lot more than one high speed run to ruin an engine like that.

[fast8]

Its really bad to do that bc u have the piston up against the vale heating it up moveing as fast it can u could bend a value

[Cooper197]

On a Subaru lik that, you're probably cooked. It won't actually rev to 8000, maybe 7250 max. Bent valves are VERY likely. If I were you I would post something on a Subaru Legacy forum, the one I use is www.sl-i.net. Its all. Legacies. The guys there have helped me before

[Bigdon]

Thanks everyone for your help! I'm having someone look at it hopefully tomorrow to see whats wrong for sure. If it is bent valves, how much would it be to repair it, or would it just be easier to get a different vehicle? And if I try to get rid of it, what should I (Or would) I ask for it/get for it?

[LifeOfLove]

Thanks everyone for your help! I'm having someone look at it hopefully tomorrow to see whats wrong for sure. If it is bent valves, how much would it be to repair it, or would it just be easier to get a different vehicle? And if I try to get rid of it, what should I (Or would) I ask for it/get for it?

Did you find out what it is yet?

I'm pretty sure you can re-do the top end to solve the problem if it is valves, I'd imagine it would run somewhere between $1,000-$1,500. Don't really know for sure though, haven't had to do that one yet, may not even be fixable for all I know. What you ask/get for it depends on the rest of the car. Generally it's difficult to get more than $1,000 for a car that doesn't run and drive. However things like leather interior in nearly perfect shape and a dentless/hardly scratched body can make it worth some money, still though, hard to get more than about $1,000.

[Bigdon]

Did you find out what it is yet?

I'm pretty sure you can re-do the top end to solve the problem if it is valves, I'd imagine it would run somewhere between $1,000-$1,500. Don't really know for sure though, haven't had to do that one yet, may not even be fixable for all I know. What you ask/get for it depends on the rest of the car. Generally it's difficult to get more than $1,000 for a car that doesn't run and drive. However things like leather interior in nearly perfect shape and a dentless/hardly scratched body can make it worth some money, still though, hard to get more than about $1,000.

The guy finally looked at it the other day. He said I blew the engine. $2-3000 to repair. Idk if it'd be worth it or not?

[Cooper197]

The guy finally looked at it the other day. He said I blew the engine. $2-3000 to repair. Idk if it'd be worth it or not?


Yeah....so honestly on a 2001 I would only have the engine replaced if I could do all the labor. Really you are talking $1,000 ish in parts for one of those, that's about what it cost for one of mine a couple years ago that's a 1999. Really it's your choice. You lose big if you bail on it now, but you could almost get a different one for that price. However, you know this car now, and a new engine would mean virtually zero mechanical issues on a car that would otherwise have very few anyway. So it comes down to what you want. $2,000 seems on the money for an engine swap. On a 2001 Legacy, I wouldn't pay $3k for it. No freaking way. For somebody experienced, it's about a 5-6 hour job as long as you are just replacing it with the same engine, which I'm sure you would. That makes it just out, and in. Plain simple, cheap. If it's more than $750-$850 in labor, you're probably over paying a bit.

[Richee]

I don't think it is a good thing for your car.. I would not do it that much.

[JIntrepid]

depends on the make, model, age of the car

[mrmee]

It can be absolutely terrible, like you just blew up your engine. Have fun with that one.

[ATOMICskittles]

It depends on three things:
1. Engine design
2. Transmission
3. Age
By engine design I mean the design of the engine's capability. For example, my parents' 2004 ford expedition is designed to the point that you really don't need to rev it to make power, at 2,000 rpm, it make practically all it's HP and torque. Then you have my parents' 2013 Ford Explorer where it makes its peak power and torque at the redline and urges you to rev. And even GM's pushrods have to rev, a lot, in order to make more power.
For transmission, some vehicles my make and model have a set amount of gears (older have 4 gears and newer have 6 or even 8!) and some makes have transmissions that learn specifically to the driver. ex. My parents' 2013 Ford Explorer
And age is pretty self-explanatory, older vehicles tend to have more limits than newer ones.

[ATOMICskittles]

It depends on three things:
1. Engine design
2. Transmission
3. Age
By engine design I mean the design of the engine's capability. For example, my parents' 2004 ford expedition is designed to the point that you really don't need to rev it to make power, at 2,000 rpm, it make practically all it's HP and torque. Then you have my parents' 2013 Ford Explorer where it makes its peak power and torque at the redline and urges you to rev. And even GM's pushrods have to rev, a lot, in order to make more power.
For transmission, some vehicles my make and model have a set amount of gears (older have 4 gears and newer have 6 or even 8!) and some makes have transmissions that learn specifically to the driver. ex. My parents' 2013 Ford Explorer
And age is pretty self-explanatory, older vehicles tend to have more limits than newer ones.

[daniel 2014]

Ok look none of these kids can diagnose your car over this forum. You need to take your car into the school autos class or a service vented and ask if you can have your cars cumputer scanned with a scan tool. That should at least help lead to what the problem is. Stop waisting your time on this site.

[Bigdon]

Ok look none of these kids can diagnose your car over this forum. You need to take your car into the school autos class or a service vented and ask if you can have your cars cumputer scanned with a scan tool. That should at least help lead to what the problem is. Stop waisting your time on this site.

I had taken it in to a garage last month, and I had blown it. It barely made it the 15 or so blocks to get there, and pretty much died. I had basically melted the cylinders and seized the engine

[daniel 2014]

Then I would take it back to whoever fixed it then and tell them to fix what they did wrong...

[Cook my Sock]

I don't think a seized engine can be fixed without it costing a lot especially if the pistons have friction welded to the cylinder block.

[Bigdon]

I don't think a seized engine can be fixed without it costing a lot especially if the pistons have friction welded to the cylinder.

Thats why I ended up scrapping it. The garage I took it to said it would be $2000 to rebuild it, or $3500 for a new motor. I just got a different car.

[Cook my Sock]

Won't be doing that again.

[billys-big-gun]

Congrats on a locked up motor. @low oil and no anti freeze to cool it the whole motor is junk, there is no rebuilding it it would have to go to the machine shop to see if they can shave the block straight if there is enough material left for a shaving , but doing a rebuild on a locked up motor that was servely over heated is far more money than a new motor with labor and parts but that sucks. i check all my fluids every time i get gas and never had any problems good luck with your next car oh yea what did you get?

[Bigdon]

Congrats on a locked up motor. @low oil and no anti freeze to cool it the whole motor is junk, there is no rebuilding it it would have to go to the machine shop to see if they can shave the block straight if there is enough material left for a shaving , but doing a rebuild on a locked up motor that was servely over heated is far more money than a new motor with labor and parts but that sucks. i check all my fluids every time i get gas and never had any problems good luck with your next car oh yea what did you get?

I'm gonna check fluids every time now or every other time I get gas now, and not drive as fast as it can go. The shop I took it to said they could do a rebuild, but no guaranteeing on how long it'll last. But I ended up getting a 1996 Subaru Legacy Outback.

[PinkFloyd]

It sounds like you could have warped the engine. I'm not an expert though. Take it to a shop.