Overheating 3.3 with HSN almost 5 turns out

[mrmattyp]

Hey Guys, need a little help here. I've searched coutless fourms, and still have an overheating problem. New to this, but have a very good understanding of this tuning thing, but still new

Outside temp here is 45F. with the factory needle setting my 3.3 gets to 300 degrees after burning about a quarter tanks.

right now my HSN is 4.75-5 turns out. LSN is 1.5 out. Up untill my last HSN adjustment out, its been overheating consistanly. It seems to be not too bad now, its at about 270, but thats still a lil high no?

Earlier i stripped my carb (long story) and have since rebuilt it. I didnt replace neither of the orings since it only had about 6tanks through it. I'm pretty sure the carb is seated properly. I sprayed a little wd40 at the join to see if it was sucking in air, and i dont think so.

So now the temps are at like 270, after 6-7 minutes run time. I still think that it will climb though witha few more high speed passes.

Its obviously very slugish being that rich. . . but any leaner and it will over heat.

I'm going to replace the o rings and reseat the carb.

Any suggestions.? Thanks in advance. These fourms are great, I've gained alot of knowlage just surfing them since christmas when i got the truck.

Matthew

 

[charliejp]

You may have an air leak. Check your fuel tank o-ring. When it's running, can you see little air bubbles in the fuel line?

 

[mrmattyp]

yes, i noticed a few, also in the back pressure line too.

The i check the oring on the tank, looked like a good seal.. . . I'm going to double check it

but a few times there were no air bubbles at all, just once or twice i noticed it. and it wasent when it was running

o ring is good nice and tight on the gas cap. . . . . .

other than the fact taht it may be sucking in air from somewhere, which i will find eventually, is there any other reason why it would be running so hot in such cool ambient temps, and with such a rich mixture?

 

[Cupooterluvr]

The 3.3 is almost made to have airleaks, I think. Even if you can't tell, it's probably there.

You'll want to seal the backplate and carb neck with sensor-safe RTV/gasket compound. Make sure all the head bolts are snug and that the shim under the head isn't bent. Replace the glow plug gasket.

Another problem is that if the LSN is too lean, the engine will run hot. Try richening that after leaning the HSN back to factory and see if it helps.

Buy new fuel lines (you should always keep a yard or so of it in your pit bag anyway) and put teflon tape in the threads of the fuel filter if you have one. Tighten the screw on top of the tank so that you need to press on the tank lid slightly for it to close completely.


EDIT: didn't see the post above this one, sorry :\

 

[mrmattyp]

new fuel lines, ill grab them tommorow. i inspected them, but could be a pin hole. I have a fuel filter in place, it has no threads but the have both ends of the fuel line tie wraped to the filter.

Thanks for the help, ill keep the updates comming.. Thanks for the assistance guys. . . .

 

[mrmattyp]

ok so i tightened the gas cap oring and i think it had a a bit to do with it. i was able to lean it out the HSN and richened the LSN. temps around 250

250 is ok from what i understand.

thanks for the help, guys, when i get a little more experience under my belt i will be glad to help other as well. This is what makes fourms work!!

Matthew

 

[rowdy18]

sounds like your piston and sleeve might be worn. i just had the same problem with a 2.5 and thats what it was.