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Engine rebuild

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Whatever dude comparing a full size car engine to a nitro engine is apples to oranges. So that's not a valid argument. The 4.6 runs fine just the way it is on it's original crank bearings. So there for I did not waste money on parts I did not need. Not mention the 2 TRX 3.3s that I rebuilt for a couple of friends of mine. Also there is nothing wrong with rebuilding a low end nitro engine just for the experience of learnig how these engines work and what goes on inside of them.
 
cwal1774 said:
Whatever dude comparing a full size car engine to a nitro engine is apples to oranges. So that's not a valid argument. The 4.6 runs fine just the way it is on it's original crank bearings. So there for I did not waste money on parts I did not need. Not mention the 2 TRX 3.3s that I rebuilt for a couple of friends of mine. Also there is nothing wrong with rebuilding a low end nitro engine just for the experience of learnig how these engines work and what goes on inside of them.
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You got lucky, that's all there is to it. Most people wouldn't risk a new p/s with used bearings.....Not to mention, used bearings can also lead to a worn block.
 
It's not luck it's called if it ain't broke don't try to fix it. I have done this numerous times with several nitro engines. They have all worked fine. Now if the bearings are bad when i tear them down then yes I will replace them. If they aren't then I see no need in spending much needed cash on parts that are still in good working order. You guys do things your ways and I will do them mine. Fair enough?
 
Just because you've had good luck with used bearings doesn't mean it's sound advise. It's rolling the dice. You ever wonder how these engines would've run with new bearings? It'd drive me nuts thinking about it.:) Bearings are crucial to tune and engine life. No reason to chance it.
 
PSHHH! Again I will say whatever dude. Nope they all ran pretty much the same as they did when they were brand new. Huh imagine that.
 
cwal1774 said:
It's not luck it's called if it ain't broke don't try to fix it. I have done this numerous times with several nitro engines. They have all worked fine. Now if the bearings are bad when i tear them down then yes I will replace them. If they aren't then I see no need in spending much needed cash on parts that are still in good working order. You guys do things your ways and I will do them mine. Fair enough?
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Can we just leave it at that ^^? Just different opinions here I think.
 
Fair enough.

---------- Post added at 9:05 AM ---------- Previous post was at 9:03 AM ----------
laton7 said:
Can we just leave it at that ^^? Just different opinions here I think.
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Different opinions yes, but I think most people would agree that it's also bad advice to use old bearings with a new rebuild kit.
 
I agree with new bearings to be safe but when your tight on cash there isnt much you can do. Even a few more $$ matters when your broke. So i call it smart to replace bearings if you can afford the few extra bucks and if not then do what you gotta do to keep playing.
 
Rebuilding a motor due to wear without replacing the bearing is pointless. However I have replaced a p/s before due to damage on the piston and then I did not replace the bearings. If the engine has 5+ gallons on it and you dont replace the bearings then you have not really rebuilt the engine you have simply replaced two wear items and left two that are still worn out.
 
The bearings weren't worn out they still felt like new. Kind of hard to wear out bearings that are constantly lubed by the oil in the fuel. Unless then engine is run extremely lean or the air filter is not properly cleaned and oiled. I tend to run a little on the rich side and keep my air filter clean and oiled.
 
Sorry bud but that just simply isnt correct. Bearings are a wear item end of story! Just becuase they feel good doesn't mean they are good. That doesn't mean you can't get by without replacing them it just means that they do wear and at some point will fail if not replaced.
 
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add 5 dollers and get the Piston Pin Retainer Set HPI 1142 to go with your piston,rod and cylinder , If I had little to spend and having withdraws from lack of bashing I to would reuse bearing and just replace these 3 things then again I would allso think about sending it out to get pinched for $25+shipping
 
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joshman1204 said:
Sorry bud but that just simply isnt correct. Bearings are a wear item end of story! Just becuase they feel good doesn't mean they are good. That doesn't mean you can't get by without replacing them it just means that they do wear and at some point will fail if not replaced.
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Sorry bud seems i did get by without replacing them because the engines still runs like champs. Besides what do you care they're not your engines or your money. They're mine I didn't advise anybody to do things my way I just asked why spend money replacing parts that are still in good working order. You guys are acting like I punched your mothers in the face or something.
 
joshman1204 said:
Sorry bud but that just simply isnt correct. Bearings are a wear item end of story! Just becuase they feel good doesn't mean they are good. That doesn't mean you can't get by without replacing them it just means that they do wear and at some point will fail if not replaced.
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Well they haven't failed yet, still work pretty good. Just because they are used doesn't mean they are bad either or mean I'm wrong for reusing them. What do you mean that's not correct? Does the fuel not have oil in it? Does that oil not help lubricate the bearings? Does that mean I shouldn't clean and oil my air filter? Does that mean that running too lean doesn't cause engine damage? Does that mean I should change the wheel bearings in my Jeep everytime I put on a new set of tires or new brakes pads? Or put new crankshaft and con rod bearings in everytime I change the oil and filter? I don't know you guys are all experts and I'm the Idiot so you tell me.
 
about the bearing thing..


i just stripped down my 10+ gallon thunder tiger.21 pro and its like new inside, little burn marks on the exhaust port on the actual sleeve which is normal i think? bearings have no play and are very smooth.....sleeve still has a slight pinch too :)

i stripped it down to the crank case, cleaned every thing except the bearings ( kept them lubed ) and when i reinstalled i covered everything in 2 stroke oil ready for when it will be run again.

i feel if its a cheap motor and the bearings have no play, front bearing isnt leaking and are both rolling very smooth.....i feel no need to change them.

if its a costly motor, say $200+ spare no expense!

i will check it all in 4 gallons time but again, if they are ok, they are ok.

as said previously ( a lot ) most consider doing the bearing change ( usually I'm guessing when they have worn there sleeve/piston out) which is there perocative but those same guys cannot tell us folk who decide not to that its a terrible tragedy and our engines are doomed ( the end is nigh kinda crap ) because thats utter b/s. if the engine is well looked after and tuned well, they will out last any component in the engine....dont forget they are high speed bearings.

i agree its bad advice to give advice on keeping used parts in a fresh built engine but its also bad advice to tell people how to look after there engine if they have had success with the way they do things......agree to disagree and be done with it.


:D


Edit: spelling.
 
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Here's the thing with bearings:

Bearings have cages in them. The cage's job is to keep the balls spaced apart. When the cage fails, like they do, the balls get grouped together and the whole bearing fails very quickly. Alot of the cages I've seen in nitro engines are plastic, and they can break with extended use, even if there are no signs of wear. That means any used bearing could fail, especially under the stress of a new piston and sleeve set.

I wouldn't consider rebuilding a cheap engine anyway. For the more expensive engines, only a fool would skip out on some cheap bearings.
 

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