Crucial 5ive-T

[crucialRC]

WTF!!! So it was 70 deg yesterday and I went to the park to make a run video. Truck starts out good then BAM, throttle servo horn comes off. No biggie, I pull out a screw from the receiver box switch and and throw it in the horn and I'm at it again. Then BAM, I landed a jump wrong and tumbled and bent up that beautiful aluminum wing. No biggie, just bent it out of the way and I'm back at it. Truck was handling great and the speed was awesome, even tho still a tad rich on the top end because the engine WAS still new. Then I come around a turn and out of nowhere she shuts off. Primer bulb empty, reed case was full of grass, and the pull start was hard as fuk to pull. WTF?? Long story short see below??

 

[Z.hb71]

damn ??? only thing I can think of is a leaky air filter or something. You find any grass or traces in the motor? Other than the totally fiddlesticked piston and cylinder.
Sorry to see that crucial, sucks ?

 

[crucialRC]

damn ??? only thing I can think of is a leaky air filter or something. You find any grass or traces in the motor? Other than the totally fiddlesticked piston and cylinder.
Sorry to see that crucial, sucks ?

I couldn't find anything damaged in the engine other than the piston and head. Couldn't find any debris in the crankcase?‍

 

[Z.hb71]

I couldn't find anything damaged in the engine other than the piston and head. Couldn't find any debris in the crankcase?‍

No idea then. Maybe a bad head to case seal ? although the gasket looks fine

 

[siblues]

Damn man that sucks.I am new here but I don't think the grass had anything to do with it but I could be wrong.That looks like metal to metal contact damage and the color of the piston looks good so not overheating or lack of oiling.I could be wrong though.How is the ring?

 

[Striikar]

Dang,wow and it was a FULL Moon yesterday. I wonder..
Hmmm.
Sorry though man that sucks.?

.

 

[DougStar]

NO WAY!????‍ Show me the head gasket and if you have pulled it off don't clean it??coz you be able to tell if the leak came from the head??

 

[alajeunesse254]

Damn man that sucks so bad! I really enjoyed watching the build it hurts to see this

 

[crucialRC]

Damn man that sucks.I am new here but I don't think the grass had anything to do with it but I could be wrong.That looks like metal to metal contact damage and the color of the piston looks good so not overheating or lack of oiling.I could be wrong though.How is the ring?

Definitely looks like metal contact. Ring was stuck in the groove where the battle scar was.

Dang,wow and it was a FULL Moon yesterday. I wonder..
Hmmm.
Sorry though man that sucks.?

.

Truley. ?Yeah, the damn Worm Full Moon is what they called it?

NO WAY!????‍ Show me the head gasket and if you have pulled it off don't clean it??coz you be able to tell if the leak came from the head??

Damn too late, I sprayer the crankcase with WD40 to see if there was anything still down in there. The bolts were tight as fuk tho.

Damn man that sucks so bad! I really enjoyed watching the build it hurts to see this

Appreciate it bruh??

 

[DougStar]

And the ring??‍

 

[Z.hb71]

We're Gunna need a Sean analysis on this one I think . Siblues makes a good point, doesn't really look like the grass is what did that to the piston. Maybe the carb got choked out and it got super lean ? Although I think you would notice this. What's the plane going forward mate?

 

[crucialRC]

And the ring??‍

Fukd at the damage area on the piston but still intact. I can't find anything missing. All the needle bearings appear to be there and the piston pin retainers are there. I'm lost?? I posted a pic of the gasket for you.

 

[DougStar]

Ok so gasket looks eh??? and you say the case was full of gas? ...........
Reed bolts are tight? Carb all tight??
Now don't take this the wrong way......gas was mixed right??
Case full of gas = hydro lock?‍?

 

[siblues]

How are the port covers are they sealed up nicely and have you taken a look at the inside of the covers yet?

 

[Z.hb71]

Test for air leaks on the case, carb, reed, port covers, and everything else. Maybe it was sucking air somewhere else ?
Im a bit stuck on the primer being empty why would that happen.

Ok so gasket looks eh??? and you say the case was full of gas? ...........
Reed bolts are tight? Carb all tight??
Now don't take this the wrong way......gas was mixed right??
Case full of gas = hydro lock?‍?

I'd check your gas, just to be safe ? know ur not a newbie but nuttin hurts ?

 

[Basher5iveT420]

Damnn what a bad one man.
Something foreign def got in there, just looking at that piston is painful.

Have you checked all bearings ?? I’ve seen similar damage when a small bb from inside a bearing brakes loose inside

 

[siblues]

I had a motor destroyed by aluminum shaving that came out of a threaded bolt hole so it could be something similar but if you didn't find any debris it is going to be tricky to figure it out especially if the color looks ok on all the parts.

 

[crucialRC]

Ok so gasket looks eh??? and you say the case was full of gas? ...........
Reed bolts are tight? Carb all tight??
Now don't take this the wrong way......gas was mixed right??
Case full of gas = hydro lock?‍?

Case not full of gas. I have to figure out what the fuk is going on. Maybe I'm doing something wrong with the mix?? I mix 1 gallon to the 28:1 mark, then shake up pretty good.

How are the port covers are they sealed up nicely and have you taken a look at the inside of the covers yet?

I checked them and they appear to be sealed and walls intact

Test for air leaks on the case, carb, reed, port covers, and everything else. Maybe it was sucking air somewhere else ?
Im a bit stuck on the primer being empty why would that happen.

I'd check your gas, just to be safe ? know ur not a newbie but nuttin hurts ?

Yeah, ever since I replaced the 5ive B engine I've been really paying attention on the fuel. How do you test the case for air leaks? Do I reassemble then add air thru the spark plug hole like a leak down tester?

Damnn what a bad one man.
Something foreign def got in there, just looking at that piston is painful.

Have you checked all bearings ?? I’ve seen similar damage when a small bb from inside a bearing brakes loose inside

I have checked the rod and crank needle bearings and they are there. I haven't taken the crankcase apart to check the crank bearings?

 

[Z.hb71]

Case not full of gas. I have to figure out what the fuk is going on. Maybe I'm doing something wrong with the mix?? I mix 1 gallon to the 28:1 mark, then shake up pretty good.
View attachment 56986


I checked them and they appear to be sealed and walls intact
View attachment 56987View attachment 56988View attachment 56989View attachment 56990View attachment 56991

Yeah, ever since I replaced the 5ive B engine I've been really paying attention on the fuel. How do you test the case for air leaks? Do I reassemble then add air thru the spark plug hole like a leak down tester?

I have checked the rod and crank needle bearings and they are there. I haven't taken the crankcase apart to check the crank bearings?

Pretty sure you can use air. I've never tested one so I wouldn't know. I'd also check the crank seals if they were leaking

 

[siblues]

I don't believe it was a oiling or a fuel issue in my opinion and that eliminates heat most likely considering nothing looks like it shows heat or overheating issues.That leaves assuming it was a leak that it let something in.The leak would have to be significant.I am sking could the carb filter let something big enough in to cause that damage and that's assuming it is a foreign object that caused it.Rod movemnet on the crank can cause similar damage but it would most likely be on opposite sides of the cylinder wall.