This piston sleeve worn?
12-10-2017, 06:27 PM
#1
This piston sleeve worn?
Hey guys, so taking apart my 3.3 and noticed my piston doesn't have free moving. Seems to get getting stuck going near the top of the crank shaft. I can't seem to figure out the issue other than it may be my sleeve but it doesn't look worn out so not sure. Here's some pictures, all help appreciated.
12-10-2017, 06:48 PM
#2
Tech Master
iTrader: (8)
you can usually tell when it needs to be replaced because you may have erratic running, may not even start but the tell tale sign is when you move the flywheel with your finger and the piston reaches the top of the stroke, it should have a good tight pinch, to the point its feels like its stuck but then comes back down. If its reaching the top and then coming back down with little to no resistance, your piston and sleeve is worn.
12-10-2017, 07:01 PM
#3
Awesome, yeah so mine feels like it's almost getting stuck, to the point I have to put a little muscle for it to go complete 360 degree turn.
Also, this sleeve is one mother f'er to get out and put back into the crank. I mean like very very hard even with lubrication.
Also, this sleeve is one mother f'er to get out and put back into the crank. I mean like very very hard even with lubrication.
Last edited by CBren32; 01-09-2018 at 01:29 PM.
12-10-2017, 07:37 PM
#5
I would agree. Ensure the piston and cylinder is oiled when turning it over without the head on it and glow plug installed. The Traxxas 2.5 and 3.3 have cast pistons - don’t turn these engines over with the cylinder dry/void of oil.
12-10-2017, 07:38 PM
#6
you have ruined that sleeve and piston by prying with tools around the top,bottom and inside the ports.
the piston also has a huge gouge on the one side i can see,
In the future,if you want to take the engine apart, leave the flywheel on the crankshaft and stick a zip tye or something softer than metal inside the exhaust port, then use your hands to spin the flywheel against the ziptie to allow your sleeve to come up so you can grab it. looking at the damage you have done to that sleeve, your better off starting over i would guess. That sleeve and piston looks ruined.
the piston also has a huge gouge on the one side i can see,
In the future,if you want to take the engine apart, leave the flywheel on the crankshaft and stick a zip tye or something softer than metal inside the exhaust port, then use your hands to spin the flywheel against the ziptie to allow your sleeve to come up so you can grab it. looking at the damage you have done to that sleeve, your better off starting over i would guess. That sleeve and piston looks ruined.
12-10-2017, 07:41 PM
#7
12-10-2017, 07:43 PM
#8
you have ruined that sleeve and piston by prying with tools around the top,bottom and inside the ports.
the piston also has a huge gouge on the one side i can see,
In the future,if you want to take the engine apart, leave the flywheel on the crankshaft and stick a zip tye or something softer than metal inside the exhaust port, then use your hands to spin the flywheel against the ziptie to allow your sleeve to come up so you can grab it. looking at the damage you have done to that sleeve, your better off starting over i would guess. That sleeve and piston looks ruined.
the piston also has a huge gouge on the one side i can see,
In the future,if you want to take the engine apart, leave the flywheel on the crankshaft and stick a zip tye or something softer than metal inside the exhaust port, then use your hands to spin the flywheel against the ziptie to allow your sleeve to come up so you can grab it. looking at the damage you have done to that sleeve, your better off starting over i would guess. That sleeve and piston looks ruined.
12-10-2017, 07:46 PM
#9
you have ruined that sleeve and piston by prying with tools around the top,bottom and inside the ports.
the piston also has a huge gouge on the one side i can see,
In the future,if you want to take the engine apart, leave the flywheel on the crankshaft and stick a zip tye or something softer than metal inside the exhaust port, then use your hands to spin the flywheel against the ziptie to allow your sleeve to come up so you can grab it. looking at the damage you have done to that sleeve, your better off starting over i would guess. That sleeve and piston looks ruined.
the piston also has a huge gouge on the one side i can see,
In the future,if you want to take the engine apart, leave the flywheel on the crankshaft and stick a zip tye or something softer than metal inside the exhaust port, then use your hands to spin the flywheel against the ziptie to allow your sleeve to come up so you can grab it. looking at the damage you have done to that sleeve, your better off starting over i would guess. That sleeve and piston looks ruined.
12-10-2017, 07:58 PM
#10
Good catch on the tool marks. Doubtful it’s ruined, but it sure doesn’t look pretty. Advice on hard liners to remove - USE HEAT and some solvent like acetone!! Soak the case in acetone for 10 minutes, drain, and heat up good and warm. The liner should slide right out. These engines’ liners’ have a slip fit. When clean and free of varnish, they should slide it easily.
12-11-2017, 06:50 AM
#11
Tech Apprentice
Late to the party here, but yea you need a new piston and sleeve, when I removed my piston sleeve I first used a zip-tie between the piston and exhaust port, next I used a cheap heat gun from Harbor Freight to heat the case really well, then I used to pliers (very carefully not to warp the sleeve) to pull it out, It caused a tiny bit of scratching but nothing major.
12-11-2017, 08:02 AM
#12
As stated, your best bet is a new PSR. Considering how cheap they are, its better safe than sorry. These Motors are complex little machines, and the better condition they are in, the better they run. All those nick's etc. on your sleeve even on the bottom of the skirt, if the brass yields there / chips / breaks, you will need a new motor altogether.
12-11-2017, 09:00 AM
#13
Tech Master
iTrader: (25)
As stated, your best bet is a new PSR. Considering how cheap they are, its better safe than sorry. These Motors are complex little machines, and the better condition they are in, the better they run. All those nick's etc. on your sleeve even on the bottom of the skirt, if the brass yields there / chips / breaks, you will need a new motor altogether.
That sheet will buff out.
12-11-2017, 09:19 AM
#14
Haha, thanks for all the help guys. Thought it was a goner when trying to take it out, couldn't get it out so decided to hulk smash it. Oh well, not the end of the world. I'll just replace the sleeve, but I honestly think the piston should be fine. Still falls on it own weight, so nothing built up. There was a very minor scratch, but other then that doesn't look worn in the least. Thanks.
