cbaker65
RCTalk VIP
Those videos were all the 3.3... and not hitting throttle at all.
Is this the idle gap? View attachment 119782
what is the best way to see if piston/sleeve is worn out?
LOL....the way you described how the engine was reacting!
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Those videos were all the 3.3... and not hitting throttle at all.
Is this the idle gap? View attachment 119782
what is the best way to see if piston/sleeve is worn out?
I mentioned a couple posts back how to check the piston/sleeve for pinch (that's for checking if it's worn out):Those videos were all the 3.3... and not hitting throttle at all.
Is this the idle gap? View attachment 119782
what is the best way to see if piston/sleeve is worn out?
You could try taking the piston/sleeve out and check the pinch. Might just be wore out and your getting a lot of blow by when it's running.
If you can easily push the top of the piston out of the sleeve, the pinch is likely pretty bad and only gets worse when the sleeve warms up and expands.
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ahh saw it didnt have the head protector so though twas the 2.5.Those videos were all the 3.3... and not hitting throttle at all.
Is this the idle gap? View attachment 119782
what is the best way to see if piston/sleeve is worn out?
Yeah, I just cleaned the top of the piston with DA, then put a line on it with a permanent marker to line it with the sleeve pin.ahh saw it didnt have the head protector so though twas the 2.5.
yes that is the idle gap, that looks more or less about right where it sits, and @olds97_lss on the previous page had a good explanation of how to check the wear on the piston/sleeve, pop them out and see how far you can push (do not force, just give it a bit of pressure) the piston into the sleeve. make sure the piston is close to the correct orientation of how it was when you took it out. i.e. intake cut out in piston is pointed towards the intake ports of the sleeve. (these are mass produced and not all the time perfectly round.)
if you do go for an engine replacement, i would also look into a dynamite .19 mach 2, they are right around 110$ and i hear many many good things about them. i have heard that the factory LSN settings are a bit lean though and should be adjusted (i can't recall what the correct ones are but I'm sure google can help you along, if not i might be able to track down where i saw that.)Yeah, I just cleaned the top of the piston with DA, then put a line on it with a permanent marker to line it with the sleeve pin.
If it is worn out, for the cost of a piston/sleeve (and when replacing that you should do the con-rod), you will likely not be far from the cost of a new 3.3, which will also have a new carb, new bearings, new crank journal... etc.
Here is a photo of putting slight pressure on piston....You could try taking the piston/sleeve out and check the pinch. Might just be wore out and your getting a lot of blow by when it's running.
If you can easily push the top of the piston out of the sleeve, the pinch is likely pretty bad and only gets worse when the sleeve warms up and expands.
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had an engine doing this, piston/sleeve were worn out. ran strong until it would die after about 3-6 minutes then would try stalling and dying then wouldnt restart until it cooled off all the way. is a chance you may be able to get them re-pinched.
the 2.5 engine, to me it sounds in the first video the idle is racing then on the bottom one it sounds like it is running rich and stalling out. what does your idle gap look like? was it changed between the two videos or where you giving it throttle at all in the first and or second video?
how hot is the engine getting? playing with the throttle, can you keep the truck running?
*if you are at factory settings* the mixture should be very rich, try leaning the HSN about 1/8-1/4 turn, see if that helps. remember to run some WOT passes between needle adjustments to clear out the Crankcase.
Lol can never have too many pictures.Here are the photos (sorry if I take too many of them)of the engine taken apart as far as I could today...are those burn marks on the sleeve normal??
View attachment 119784View attachment 119785View attachment 119786View attachment 119787View attachment 119788View attachment 119789View attachment 119790View attachment 119791
So you saw my video.....lol......I forgot to mention a bearing was messed up on the clutch bell, I have ordered new ones they are the metal type...do I need to grease those?That almost goes plum through the sleeve!.....?
So you saw my video.....lol......I forgot to mention a bearing was messed up on the clutch bell, I have ordered new ones they are the metal type...do I need to grease those?
Thanks, for my next trick I will take apart the 2.5 and see what that looks like now that I have more knowledge.....Lol can never have too many pictures.
much as i hate to be the bearer of bad news, that piston/sleeve to me looks about done for, as far as the pinch. once the sleeve warms up the piston will be free to go up even further increasing clearances between the sleeve and piston thus loosing compression that much more.
as far as the burn marks, that seems to be on the more high side of normal to me. usually see them, but that i have seen not quite to that extent.
Thanks wasn't sure about grease someone online mentioned servicing them more often than the rubber sealed ones that's all. gonna disassemble the 2.5 and if that is in the same condition I will either do the swap of the 2.5 to 3.3 upgrade thru Traxxas or get the Dynamite Mach 2 that someone mentioned and still try to get the 3.3 repinched have to find somewhere to do that tho.The clutch does not have nothing to do with this matter ,but no ,I wouldnt think that you need to grease any bearings!
If you insist on trying to keep this engine ,the alternative route that you can go ,is to have the sleeve repinched ,an
if all else fails ,you only lose 20 or 30 bucks!
I had an engine repinched ,an it still runs good to this day!
Thanks wasn't sure about grease someone online mentioned servicing them more often than the rubber sealed ones that's all. gonna disassemble the 2.5 and if that is in the same condition I will either do the swap of the 2.5 to 3.3 upgrade thru Traxxas or get the Dynamite Mach 2 that someone mentioned and still try to get the 3.3 repinched have to find somewhere to do that tho.
Today I let it warm up and then got it into my yard with help from the wife...ha....(it is too much for me to carry with the controller and starter on my own I forgot to mention I am in a wheelchair so I always have to wait for help when I want to run it) It ran for a bit probably a total of 5 minutes I never went full throttle but then it obviously overheats and I will have to wait a while to run it again. Sorry for the long video I do not know how to edit them yet....And don't pick on my Dog (Peanut Butter)....HA
I won't, In fact went out this morning to adjust the slipper (not mine) the trucks...HA....engine cranks but will not start even with new glow plug the light on my starter indicated glow plug not igniting....:-(, So another time I will remove engine and check it for any damage that might have been caused by yesterdays "run"No ,it is not right!
Your engine is running fine ,the clutch or something is slipping very badly causing the engine to over rev causing the
heating problem ,you should not keep running it like that!....