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Stall then no start

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flandersander

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my tmaxx starts fine cold then it stalls once it gets to about 100 dagrees. And it won't start again. it bogs right before it stalls. whats wrong?
 
well I bought it used and am not sure how long it has been since he changed the sleev and piston. how do you test the compression?

Edit: that was a stupid question u use a compression tester. what kind of price am I looking at for a compression tester? Or is there a different way?
 
easy.. turn the fly wheel.. you should feel some resistance (compression) after you get it heated up and it cuts out.. check your compression again (heat causes metal to expand thus making a bigger gap between piston and sleeve) if it is easy to turn flywheel then it is losing compression
 
u mean If I can just spin it over? as if i had the glow plug out? I will do that but not until tomorrow. it dark outside. or can I test it cold? cuz there is lots of compression when its cold.
 
flandersander said:
u mean If I can just spin it over? as if i had the glow plug out? I will do that but not until tomorrow. it dark outside. or can I test it cold? cuz there is lots of compression when its cold.
Click to expand...

umm.. leave glow plug in.. but yes.. kind of.. it could have weak compression
 
ok i tried it but am unsure what it means. I can turn it but it is not super easy. in fact i can't turn it with a bent finger. it has to lock. not sure if that helps but it is way tighter than without a gp.
 
flandersander said:
ok i tried it but am unsure what it means. I can turn it but it is not super easy. in fact i can't turn it with a bent finger. it has to lock. not sure if that helps but it is way tighter than without a gp.
Click to expand...

thats a good thing.. now after it stalls out.. do that same test as soon as it happens..
 
ok I will tell you tomorrow. but if it has that much cold then wouldn't the piston and sleeve both expand? or would it make that much of a difference?
 
usually in an engine the piston will expand more than the sleeve once it gets up to temp. Pistons are engineered to expand and take up the clearence between the piston and sleeve. The sleeve is pressed into the block limiting the amount that it can expand.
 
So it will have MORE compression than cold? So its not that? Then why does it stall out?
 
Sounds like a lean issue. Usually when you start it cold you'll have to turn up the idle because it's really rich. My buddy had the same problem as yours and his HSN was way too lean. Once it warms up it gets too lean to run.
 
yeah it does seem like it is getting not enough fuel. I will try both right away and report back in like an hour.

ok well I tried it. And there is a considerable less ammount of compression when it is warm. So do I need a new piston and sleeve? Also why is there less compression when warm? it makes no sense to me.
 
Ok well I tried it and it has substantially less compression. Sorry if this has been posted already. What next? do I need a new piston and sleeve? Or can i do something about it? What about pinching the sleeve? What is that?
 

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