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Think my sleve is shot???

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B

big jilm

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  1. Bashing
How hard should it be to put the piston at TDC if you have the mill torn down... Nothing on it except the flywheel. Carb,header, and backplate all removed...

I can turn the flywheel with no resistance on both of my mills... I can here them sliding at the pinch zone but no resistance... Figures I would buy two trucks and not get a good motor in either.... They both run strong and you have a hard time turning the flywheel when they are all put together... I just keep getting high temps. I'm sure thats what killed the pinch..
I heard you can re-pinch the sleves. What would that cost and is it effective????
 
Where ya at there guru's ???? Need a little help... I think I know the answer but would like to be wrong...
 
I'm no guru but I can tell you a good broken-in engine will have little to no resistance when the head is removed. The idea of the pinch is a means to achieve a wear-in working fit for the piston sleeve so it will make compression. Compression is what you must have for the engine to run properly.
The high temps could be a number of things, if they start good hot and cold and run strong the piston sleeve are fine.
Do a search, getting a pinch is relatively inexpensive and works well if done properly.
 
Yeah, thats tha thing. Both engines run strong but they run hotttt.. Like 300 hot... I just sealed them up and will get them all tightened up in tha morning... I just can't get the temp down. Hopefully sealing them will work..

We will see. I'm broke so if they are shot I will have video posted of me blowing them up.. They will run regardless!!!
 
What are they? BTW, I know it's not the opinion of the majority on here but 300 isn't really bad. I run my Savage 25 in the mid 290s all the time. Over 6 gal and still very tight/hard to pull with a pull start.

I wouldn't want to see it over that, but it really shouldn't be hard to get it just under the 300 mark.
 
stock trx 3.3's.. I wouldn't worry too much but I can start to see the performance drop off. One run strong at about 270 and the older one was crazy the other day at 260 and stayed at that temp but I had just sealed it. I turned it off and when I started it the next day it shot straight back to 300... I have them both torn down right now..

I'm running rich at these temps also.. pretty much factory...
 
Most engines usually need small tweaks everyday to keep them tamed.

Also there is more to tuning than just adjusting the needles. Glow plugs/fuel choice will effect the tune/temps too.
 
If you have them torn down, take the piston/sleeve out of the engine and see how far the piston easily pushes into the sleeve. If it makes it flush with the top of the sleeve or further, they need pinched. If they are in good shape and your low on dough, just pinch them, $25 a piece at www.rayaracing.com.

Geez... I sound like a broken record tonight! Second or third time I posted something similar to this. Not that it isn't true, just seems like lots of folks are fighting tired engines these days.
 
funds are low these days...;)

Well I sealed and put them back together.. One is ready, Great temps and lots more power. Still have problems with one but I think I found a leak in the tank. The idle is very high and doesn't want to come down. Guess I'll be tearing this thing down again..

Thanks for the info on the pinch. I saw it before but couldn't remember who had posted it...
I'm too poor to pay for a pinch... Hard times brotha.. Thanks for the help guys..
 
With the motor out and the glow plug installed, turn it over untill the piston is at BDC, then put a good bit of after run oil in the exhaust port straight ontop of the piston. Now turn the flywheel. Watch the piston through the exhaust port, after the last window on the piston goes up look for bubbles coming down in between the piston and sleeve. They will be very visible through the exhaust port. If you see bubbles you are leaking some compression. Also with the glow plug removed the engine will turn over with little to no resistance, this is normal, most of the resistance comes from the compression not the pinch.

My 1 1/2 year old 3.3= lots of bubbles
My 2 month old .26 max= no bubbles
 

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