3100 overheating and heater not working

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Guest

3100 overheating and heater not working

Postby Guest » Sun Mar 16, 2003 2:07 am

I have a 3100 Monte (used to have a beretta though!) and it started to over heat, and I noticed the heater was blowing very cold air.  Popped the hood and saw the coolant was boiling up in the resevoir.  Figured thermostat must be stuck shut.  Changed that (pain in the ###!  whoever designed the therm on the 3100s should be sentenced to life changing them!).  Still had the same problem.  Bled the system using the bleed screw (just opened it until it was giving out pure coolant instead of spurts of air and coolant (50/50)), and it was fine for about a day.  Next day, same problem developes, and I noticed the resivoir tank overflowing and bubbling!  I opened the bleed screw again and it was just shooting out tons of air, I left it open for a long time and it continued to just give out air!  (needless to say the tubes from the radiator to the thermo isnt that pressurarized).  One more thing I noticed, this might not have anything to do with anything but sometimes when this is happening if I floor the car from a stop to around 75 mph the problem goes away (temporarly), unfortunately thats not an option all the time.

Any input would be appreciated!  Oh and thermostat was put back correctly and everything (correct direction), fans work.  Question being why would the system keep building up air?



Guest

3100 overheating and heater not working

Postby Guest » Sun Mar 16, 2003 10:07 am

Low on coolant, and was blocked by an air pocket. May have a bad head gasket, or is loosing coolant into the oil through the intake gasket. Any mayonaise looking stuff on the underside of the oil fill cap? If yes, coolant in the oil. If white looking smoke comes out the tail pipe and really never goes away, head gasket.



Guest

3100 overheating and heater not working

Postby Guest » Sun Mar 16, 2003 12:15 pm

JC, thanks for the reply - my low coolant never came on, and the res was always full (now it even overflows).  Im going to bleed it again and hope it doesnt come back again.  Interestingly I had the mayonaise looking stuff on the oil fill cap, but the oil wasnt foamy, so I figured its just condensation since it is freezing over here.  Would a a bad intake gasket cause the air pockets to form though?  And for bleeding the air out, would you recommend using the bleed screw that is right before the thermostat as the haynes manual suggests, or could I just open the radiator cap and let it run?  (the bleed screw takes forever!  Thanks again!



Guest

3100 overheating and heater not working

Postby Guest » Sun Mar 16, 2003 1:12 pm

all it takes is 1 bad overheat and those aluminum heads will warp to hell. did you drain your oil to see what it looks like?



Guest

3100 overheating and heater not working

Postby Guest » Sun Mar 16, 2003 9:27 pm

couple things, makes no difference if it's foamy or not, intermix is intermix, and that spells a ruined bearings. If you're using the pink antifreeze, (dexacool) then it might be clogging the system. The "boiling back" is probably from a bad head gasket blowing back into the cooling system.



Guest

3100 overheating and heater not working

Postby Guest » Mon Mar 17, 2003 2:04 am

JCZ26, I believe you are right, I do have a blown head gasket (I didnt want to admit that).  I have been using the dexacool - but I think the main problem is the head gasket causing the boiling back as you said.  Ive done all my repairs myself, but I dont think I can handle the head gasket, looking through the haynes manual, it seems like a major pain in the ### - oh well, mechanics have to make a living off something :rock:

Anyways thanks for your help!



Guest

3100 overheating and heater not working

Postby Guest » Mon Mar 17, 2003 8:10 am

Beware though, you MUST replace the head bolts when changing the heads or head gaskets. The bolts stretch, and will not torque properly if you reuse them. Reuse may lead to uneven torque after warm up, resultinging in head warping, and even worse, I've seen it where a bolt has broken due to reusing the head bolts.






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3100 overheating and heater not working

Postby stang&2Birds » Tue Mar 18, 2003 2:30 am

Quote (JCZ26 @ Mar. 17 2003,08:10)
Beware though, you MUST replace the head bolts when changing then heads.

I got mine from Advance Auto.  They where pretty cheap and a brand name.


Joe -- 94 Olds Achieva Quad 4 HO ; 92 Olds Achieva Quad 4 SOHC; '69 Firebird 350 ; '77 Olds Cutlass (Yes, I have *4* GM cars. :)).  86 TBird & 86 Mustang GT with Cobra brakes & ABS.
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Guest

3100 overheating and heater not working

Postby Guest » Tue Mar 18, 2003 7:20 am

Quote (stang&2Birds @ Mar. 18 2003,02:30)
Quote (JCZ26 @ Mar. 17 2003,08:10)
Beware though, you MUST replace the head bolts when changing then heads.

I got mine from Advance Auto.  They where pretty cheap and a brand name.

That's cool, but I spend the extra money from the dealer, this way if it breaks, I can blame gm if something goes wrong, and fight for a new motor. He, he, scream enough they usually give in, better than bad publicity. :laugh:  :laugh:



Guest

3100 overheating and heater not working

Postby Guest » Tue Mar 18, 2003 10:13 am

A friend is doing it for me for pretty cheap - $450 - that is if the head isnt warped or anything though.  :)



Guest

3100 overheating and heater not working

Postby Guest » Sat Mar 22, 2003 7:30 am

$450 isn't cheap. The head gasket is 15 bucks each (recommend doing both), the intake set is 50 if the car is 96 or newer, and the bolts are about 22 bucks per side. Most friends help out and say, you pay for the parts, I'll fix it. ???



Guest

3100 overheating and heater not working

Postby Guest » Sat Mar 22, 2003 8:20 am

i did my head gaskets in two days... man it was a pain in the ### but it wasnt hard... and i never let my car overheat so i didnt warp the head, i noticed the smallest leak before it ended up causing a overheat.  The car ran fine except for when it sat warm, it would spray coolant into a cylinder and when started it would stop leaking, but man there was a cloud of smoke.  But its all better now, and i have a new set of heads thanks to JCZ26 ready to go on :) plus a 3400 top end, now i just need head bolts since i didnt replace those last time.  :D



Guest

3100 overheating and heater not working

Postby Guest » Thu Apr 17, 2003 2:43 am

Thanks everyone for your advice!  Got the head gasket changed and everything seems to be fine :)  Now a new problem has arisen though - When I take the oil cap off, there seems to be I think its called "blow by," steam comes out (only when the engine has been running for a while).  Is this a big deal?  I hope not!  :rock:




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