Hey guys.

The last time I used my Duratrax Evader ST I crashed it into a bush, flipped it, and broke the rear suspension tower. I left the engine running until it was out of nitro, and left it on the table. I told myself that I would put after run in it later when I got home from work. Well, here we are almost two months later, and I just realized that I forgot to put in after run oil.

Is there reason to suspect that my engine has suffered substantial damage? Or should one time of forgetting not hurt the engine? Is there anything I should do, aside from putting the oil in now, that I should do to check the health of the engine?

I am worried I may have just ruined the engine.

Any thoughts on this issue would be helpful. Thanks.

I never use it other than as an assembly lube if I am putting an engine back together. I've had engines sit for 20 years in a drawer, and start right up.

Most modern fuels have after-run oil in them...well, I'm not sure if it's "most", but none the less even if your fuel doesn't, once the alcohol evaporates, it leaves an oil residue on things.

Most internal engine parts won't rust as they arn't steel. They can corrode, but I've never seen the inside of an engine corroded before. The bearings can rust, but usually have enough fuel residue (oil) on them to prevent that for a long time.

The biggest issue I've had with long term storage is a gummed up carb. Even though the tank was run dry, this fuel residue can gum up a carb pretty quick. Sometimes that makes it hard to start, but often it will start, but not run very well until the residue (gum) is washed away by the new fuel going through it.

None of this is to say after-run-oil is a wasted effort, but I certianly don't think a few weeks, or even a few months, without it will hurt anything.

ARO is WAY overrated....

OK, I say that cuz for years I ran Sidewinder fuel, which is high in oil.. But I mean, what, %13 oil compared to the %11 Tornado I run now or whatever... Insiginificant...

Don't worry about it.. I do use it, but only if I know they'll be sitting for a long time. And more for peace of mind to cover any doubts than any real belief that it'll make a big difference..

Don't sweat it..

I never use after run oil. I have an Axial .28 Spec 1s, and it has about 8 gallons on it now and has only seen after run oil a handful of times. The ONLY time i use ARO is when I know the engine is going to be sitting for a few months without running. However, if its in the house, and not out in a cold garage where it is subject to temperature changes, it should be fine anyways. You havent hurt anything at all. No need to worry. [8D]

Eric

Thanks for the information. It really helps put my mind at ease. Wouldn't want to have to replace the motor just yet.

I thought After Run was mandatory, but your posts lead me to believe otherwise. Thanks.

The manuals will say that you MUST put after run in just so that they won't get sued over saying that you don't have to do it. I never use after run because you don't need to do it!

I stopped using after run oil in the mid 90's, no problems. I don't think there is anything wrong with using it. I don't think it hurts anything either. If you're going to store a car for a very long time then it wouldn't be a bad idea. I store mine over the winter with no after run oil and they're just fine the next season.

aro isnta have to or die. i use it when i know its going to sit for a week or two. just because it makes it easier to start after sitting. but it wont hurt the engine not using it. lots of people use to much of it. to much will cause a compression lock and ruin the glow plug

Im sure your ok, thats not too long.
Does your engine spin over ok ? if so...Fire it up and go!

I've never used any and I've never had any problems with engines rusting up. But that's probably because I make sure to run them out of gas when I'm done. Or pinch the line and run them dry that way. I would be more concerned with whether the crash itself damaged the engine than I would if it was gummed up or something. If it spins freely and has good compression it should run just fine.

A bigger concern for me rather than ARO is ensuring I set the piston to bottom dead center after every run....

you use good fuel, run it dry and disconnect the hose from the tank and your safe. i never had a engine gum or rust, even letting one sit 2months still attached to a full tank of fuel.

after run is always good for long term storage, dry starts, break ins and if you want a extra level of protection for your high end motor, not nessisary for the most part.

Thanks for all the reply's. Now comes this question...what happens if I used to much after run oil. How do I clear the engine if it locks? Or just clear it out before it even has the chance to lock when trying to turn it over?

I guess I won't be using after run anymore then. Based on all of your reply's.

Thanks again.

flip it upside down with the glow plug out and crank it

I've had engines sit for 10 plus years with no ARO and fuel left in the tank/engine/carb. All I had to do was take it apart, clean out the gunk, put in a new glow plug and run. That engine is now over 20 y/o and still runs fine.
If I know one will sit for a month or so I'll use ARO but if I miss adding it I'll just do the clean up needed and run the engine.

Pull the GP and turn it overa few times. Pop the olug back in and fire it up.

Once in a while I will used after run oil (WD-40), but not all the time. You'll be fine.

You don't even have to flip it. One good, solid rip of the pull starter will shoot whatever's inside the engine a good three or four feet straight up.