Car rolling when in gear after driving on track

[Alicks]

Lol dan people are struggling to understand. My car is always fine when I leave it in gear. Compression holds the car. Regardless of it being first, second or reverse. The point people are missing is that it's fine normally, I drove in from a lap of ring. And compression didn't hold my car.
Forget what gear I had it in or which way the slope was. It holds normally, but didn't after a lap of the ring. All I wanted to know was if anyone had any other thoughts as to weather it may be thin oil, hot clutch? Not what your driving instructor told you when you had lessons!!

 

[Alicks]

Thanks El boomo, someone actually applying mechanical knowledge at last.

 

[nellly]

when it was rolling forward was it smooth or was it stop start as it keeps fighting the compression on the engine when the crank turns

 

[Alicks]

It was pretty smooth. No jerking or anything just a very smooth run over the compression. Which in my head makes me think more clutch. I just questioned it because it's literally done no more than 6000 miles and it was a genuine honda one. Although I do drive it hard and quite a bit had been on track

 

[Mark_teg]

If it drives it won't overcome the clutch on a slope.

I don't think there's anything to worry about!
As long as it drives fine, just use a brick/chock in future..

 

[emmsyDC5xx]

Thanks El boomo, someone actually applying mechanical knowledge at last.

People possibly didn't understand your posts..
People were genuinely trying to help with what they thought you were asking..
You LOL at the people who took the time to respond and genuinely try to help because it wasn't the right type of reply or 'mechanical' knowledge for you or what a driving instructor told them....

Nice!

 

[Alicks]

My point was I didn't ask what gear should I leave my car in on a up slope or down slope. Again I still stress that I can't see what difference it makes other that gear ratios etc. I said it happens after being on track, after everything has heated up. Apologies if my reply offended anyone, i never intended too but no one has applied any knowledge to these theory's they're suggesting.

 

[dave7368]

haha.. i can't believe you're worrying so much about an issue that you say doesn't bother you...

 

[Coldfuse]

Are you all drunk or something? the car won't roll when it's in gear regardless if its 1st 6th or reverse... The engine's compression will not allow it.

When i was at my folks house before i moved out, their drive was a pretty steep slope and i would always park in nose first because of the orientation of the driveway. I would often leave the Teg in 1st after a quick drive and leave the hand brake off.

Ultimately, Alicks, i would say that it is a weird problem. Does it stop rolling again when you have left it to cool down again for 30 mins or so?

 

[davidpingu]

http://www.toyotanation.com/forum/149-10th-gen-corolla-2nd-gen-matrix-general-discussion-forum/397134-help-my-car-rolls-while-gear.html

Have a look at this. I read a few others too and everyone agrees that it's compression that holds the car so I think your own assumptions were right to be honest or near enough. I think it's a combination of the hot oil being thinner and it still being fresh in the cylinders.

As it drains back down to the sump through the cooling process it will be slightly harder to turn the engine.

 

[C&S Evo7]

hmmm,

the reason you should select reverse when facing up hill is to prevent the engine turning the wrong way, you should NEVER turn an engine the wrong way, as the cam chain and tensioner system is not designed to be "pulled" from the long side of the chain (its a bit difficult to explain) it needs to be driven in one direction only, sometimes there are mechanically driven pumps etc in the system too.

why your car was able to roll down forwards when in gear (any gear would work except reverse) really is a mystery to me, i dont think the oil would make any difference as you still have the same compression on a hot engine (certainly enough to stop the car) my only suggestion would be a very hot clutch which allowed it to slip.

 

[El_Boomo]

hmmm,

the reason you should select reverse when facing up hill is to prevent the engine turning the wrong way, you should NEVER turn an engine the wrong way, as the cam chain and tensioner system is not designed to be "pulled" from the long side of the chain (its a bit difficult to explain) it needs to be driven in one direction only, sometimes there are mechanically driven pumps etc in the system too.

why your car was able to roll down forwards when in gear (any gear would work except reverse) really is a mystery to me, i dont think the oil would make any difference as you still have the same compression on a hot engine (certainly enough to stop the car) my only suggestion would be a very hot clutch which allowed it to slip.

That's the way I've always thought. The suggestion was to select reverse downhill which I think is what rattled cages.

 

[Topgeezer]

Hopefully it's not a lack of compression allowing it to turn over easier when in gear?

T.G.

 

[Saint Matt]

If compression was low enough for that then it wouldn't run, or at least wouldn't run very well at all.

 

[Alicks]

It still runs fine, I'm not loosing oil so it was
Thinking more hot clutch. It's made a groaning noise since I've got back so guessing it's glazed over or something