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engine needs fixing

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cameron

cameron

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I've got an old rc car engine.it does not start up but i was hoping i could get it working.the problems are when i pull the pull cord, it just winds in very slowly and it also sounds like there is no pressure building up in the engine because it is very easy to pull it (which would suggest a compression problem)would an engine rebuild fix it and if i do one, is there anything i should look out for.i also must mension that i have no budget.
 
Take off the pullstart, clean the one way bearing with some plastic safe solvent. Then hit it with a shot of wd-40. Get some fresh fuel, 2 new glow plugs, and charge up your glow ignitor or get a fresh battery in it. Make sure the fuel tank isn't all gummed up and try to fire it up. Just add the fuel, blow in the pipe to tank line until fuel reaches the carb and give it a whirl. You may have to open the carb to get it primed but it should fire. Then you can determine if it's needing a rebuild or not. I don't know what engine you've got or how long it sat, but if it turns, it should run.
 
2revo1maxx said:
Take off the pullstart, clean the one way bearing with some plastic safe solvent. Then hit it with a shot of wd-40. Get some fresh fuel, 2 new glow plugs, and charge up your glow ignitor or get a fresh battery in it. Make sure the fuel tank isn't all gummed up and try to fire it up. Just add the fuel, blow in the pipe to tank line until fuel reaches the carb and give it a whirl. You may have to open the carb to get it primed but it should fire. Then you can determine if it's needing a rebuild or not. I don't know what engine you've got or how long it sat, but if it turns, it should run.
Click to expand...

cheers ill give that a try

the car is about 20 years old
 
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i did that test today where you hold the flywheel and you see how long it can support the engine.it holds it for about 1 second so I'm guessing there is a big problem because the engine is meant to be able to hold for about 10 seconds.
also,what could i use as a good pull cord instead of buying one.all i have is string.could i coat it with something to make it strong
 
cameron said:
i did that test today where you hold the flywheel and you see how long it can support the engine.it holds it for about 1 second so I'm guessing there is a big problem because the engine is meant to be able to hold for about 10 seconds.
also,what could i use as a good pull cord instead of buying one.all i have is string.could i coat it with something to make it strong
Click to expand...

Ii red that you can use the cords off window blinds ;) ...i know they are plenty strong
 
when i tried to use the car today, i turned it all on but the servos showed no sign of life. i tried loads of different batteries and a battery pack and there was nothing but when we last used it it worked fine
i would really like to know what is wrong
 
cameron said:
when i tried to use the car today, i turned it all on but the servos showed no sign of life. i tried loads of different batteries and a battery pack and there was nothing but when we last used it it worked fine
i would really like to know what is wrong
Click to expand...

did you check all the wires and plugs ?? maybe something is not making contact somewhere .....I'm guessing ...since its an old car ..it must have radio cristals ...maybe that the problem ...take them out and put them back ..maybe they are not making good contact .....

i dont know much about cristals ...i never used them..i have the 2.4ghz radio
 
its fixed now.I'm up to the stage of starting it now.does anyone have any tips so that i would find it easier to start it and it would start quicker

just to let you know how old it is,the one way bearing isnt in the pullstart.i have to remove the pullstart then remove a plate then the one way bearing is there,it is not in the pullstart
 
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Preheat the engine with a hair dryer or heat gun, make sure the piston is at bottom dead center before you try to crank it.
 
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I AM SO ANGRY the one way bearing seems to of just broke over night:OMG: it is not catching on the shaft anymore and like i said i have no budget so i dont have anything i can do :headscratch: :headscratch: :headscratch:
 
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Spray it out really good with nitro cleaner or carb and choke cleaner. Brake cleaner works too. It should grab if it isn't broken.
 
Not knowing your engine - is it possible that you installed the owb backwards and that's why it's not catching?
Try cleaning it again - and clean the shaft too.
I use nitro balster or denatured alcohol for this task, but use what you've got handy.
I also use some owb oil that I got about 10 years ago instead of wd-40, but a number of folks here use wd-40.
Only use a little of it though - it may be slipping because you used too much.
Test it out before you reassemble - it should catch when you spin the shaft clockwise.
If it's properly installed and doesn't catch, it's probably broken.
If that's the case send a photo of the owb - maybe someone can identify a replacement part for you.

At this point in it's life it's unnecessary if this that you heat this engine up with a heat gun or hairdryer.
You do that with a new engine that has a lot of compression.
Your engine looks long in the tooth and from your description to be down on compression.
BTW - Your engine looks to be about 10 to 15 years old - give or take.

Assuming that you've reassembled it and it's turning over nicely, all you really need to do is:
A. Prime it to the point that the fuel reaches the carberator.
You can prime it like 2revo1maxx described or use the plunger primer on the tank.
If it's been sitting around for a long time, I would make sure that the carb isn't gummed up to the point where the fuel won't flow properly through the HSN.
B. Turn on the controller and receiver.
C. Plug the ignitor onto the glow plug (make sure it's charged/has a fresh battery)
D. Pull on the pull-starter with short but quick tugs (your string is only so long and you don't want to break the pull-starter). It should show some signs of life.
 
well i tried to start it but when i put fuel in it, within 5mins the fuel would somehow get to the owb, cover it in fuel no matter how much fuel i put in it and make it keep slipping.on a good note though, when i got a chance to try and start it,it burned fuel but for some reason the car didnt actually start and also smoke came out of the carburetor and not the exaust which was unusual.any suggestions on why the car didnt start,the fuel always got to the owb and thy smoke came out of the carb

btw does anyone know how i could unblock the hsn the fuel can't seem to get to the carb
 
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There's several ways...
You can always try putting denatured alcohol (dna) into the fuel line and/or tank and blowing or pumping (priming) it through.
To see if that works pop the air filter off and open the barrel like you're giving it gas. The dna should be making its way (spraying) into the venturi.

You can also unscrew the HSN and see if it's gunked up inside there.
Remember where it was before you messed with it so you can reset it.
Clean the HSN and banjo fitting as well as the inlet port that sprays the fuel into the venturi. You may need to pull the carb and simply soak it in dna

As I mentioned, I'd use dna or nitro blaster as both do a nice job of desolving deposits.
I've tried automotive carb and choke cleaners, but in gunked up engines they seem to leave residue behind and I end up having to clean that out with dna anyways.

If it's blowing smoke back through the carb, my guess is that your piston/cylinder has no compression and it's escaping back out the intake side of the engine. Might also be that the owb is installed backwards (?) - just guessing...

BTW - If you're thinking that the HSN is clogged, how is the fuel getting all over the owb?
 
well I'm sure the hsn is blocked because if i try to prime it i blow really hard and it feels blocked and the fuel doesn't move through the line
also fuel gets on the owb because the owb is inside the engine i put fuel in the carb to prime it that way, it gets to the piston then goes somehow to the bottom of the engine where the owb is
btw i can't put the owb inside the wrong way because it has a notch on one side that the botton of the piston ataches to to make it spin

does anyone think that it is not worthit sorting this car out because i have another car which is my older brothers .the problem on there is the pull cord needs the spring recoiled which i can do the owb needs a good clean and he is missing a front axle.
however he has a big problem that his exaust has a missing screw which makes the engine have a huge air leek does anyone have any suggestions on how i could seal it or should i get another screw for it or should i stick with the older car
 
Do not dump fuel in the carb. When you blow into the exhaust line you should try holding the throttle open a bit. The fuel should flow through. Make sure to stop priming once the fuel reaches the carb.
 

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