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HPI RS4 engine

HPI RS4 engine

Old 03-19-2014, 10:54 PM
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Hello,
I was given a HPI RS4 2nd hand from my bro who lost interest. I know the car sat in a gargage drawer for over a year or 2. I started to break down the RS4 for a good cleaning, but noticed the main purple gear doesn't turn (refer to pic), and crank cord won't budge. Any suggestions? Could the engine be locked up?(is that even possible)
Please be patient as I'm a complete newb to the RC scene.


Thank you
Attached Thumbnails HPI RS4 engine-rs4engine.jpg  
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Old 03-20-2014, 09:30 AM
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Originally Posted by Rec0n
Hello,
I was given a HPI RS4 2nd hand from my bro who lost interest. I know the car sat in a gargage drawer for over a year or 2. I started to break down the RS4 for a good cleaning, but noticed the main purple gear doesn't turn (refer to pic), and crank cord won't budge. Any suggestions? Could the engine be locked up?(is that even possible)
Please be patient as I'm a complete newb to the RC scene.


Thank you
What you have here is an engine that had nitro fuel residue left in it and the oil gelled up and seized it. You can take a heat gun/hot blow dryer and heat the engine up to free it. Once you do that, you will need to take it apart and thoroughly flush out the crud and check the interals for rust. If there is no rust, especially in the bearings, you are fine. Just lube the parts up with after-run oil, re-assemble the engine and go from there. If the bearing are pitted and/or rusted, you will need to replace them are you will have other issues with the engine down the road. The same will be true if the crank and rod are pitted and/or rusted (check the bushings in the rod ends for pitting). Be careful when taking the pullstart mechanism off the back of the engine as not to let the coil with the recoil spring pop/fly out of the pullstart housing. If it does, forget trying to recoil the spring and get all that stuff back in the housing, just buy a new pullstart unit.

Last edited by JLock; 03-20-2014 at 11:08 AM.
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Old 03-20-2014, 11:47 AM
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What he said. Also, the purple thing isn't a gear, it's the flywheel. It should NEVER EVER touch anything else.
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Old 03-20-2014, 10:18 PM
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The basics of trying to run an engine that has not been in use for years would be throw out the old gas and change the fuel line.
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Old 03-20-2014, 10:18 PM
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Always use fresh gas!!!
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Old 03-20-2014, 10:19 PM
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One more thing when your done using it throw away the gas.
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Old 03-20-2014, 11:54 PM
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I just use a plastic syringe with a bit of fuel tubing on the end to suck excess fuel out of the fuel tank, so I can reuse it later. I make sure not to squirt it back into the bottle of fresh fuel, though.
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Old 03-24-2014, 08:34 PM
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Remove glow plug,see where piston froze, if at or near tdc, last time it ran it was not stored a bdc. Use ARO , LET IT SOAK 30min. Use pair of channel lock, grab around the flywheel, and turn the opposite direction the pull srart. This will not put so much stress on connecting rod and bearing. Once it breaks loose you can probably use you pull start. Then you can decide what you want to do.
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Old 04-05-2014, 09:34 PM
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The one-way bearing in the pullstarter will prevent you from rotating the crankshaft backwards. Geezatec's suggestion will only work if you temporarily remove the pullstarter first.
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Old 04-06-2014, 04:24 AM
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engine will be just fine unless there is internal damage. A buddy of mine has a .40 os airplane engine sit for 10 years and was all seized up. We took CRC spray lube or wd-40 and got the engine to free up and we took it all apart and cleaned everything with wd-40 piston rod sleeve crankcase crank. It had some rust on the components and we just cleaned it up. polished everything up and got the engine running. we preformed a breaking for the engine to make sure the engine was ok and just make sure everything was seated in. Then we flew the plane. He put about 2 1/2 gallons threw it before the plane crashed.

unless there is physical damage to the internal engine components don't worry just clean the entire engine up and start it up.
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Old 04-09-2014, 08:38 PM
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I still have one of these, was my first r/c car ever, bought it in 1997 with the HPI .15FE Nitro Fail...

I ended up putting a .12cvrx OS engine in it which was a smaller engine and ripped a whole mess harder than the .15...

I haven't ran it in 10 years though.

the kit itself was nice, needed all the upgrades like two speed and everything. Let me know if you need any help with the car, I know it inside and out.
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