Now we're at the root of the problem, why did it overheat, not because of the heater core. It may have had a bad radiator, leaking and you didn't notice it, or it might be a bad water pump, also leaking and you didn't notice it, either way, low on coolant and overheating. Very good chance you have a warped head and leaking head gasket at this point, check for water in the oil, oil residue in the radiator, and do a compression check. Go forward from there, from the way you describe it I'm pretty sure you are going to find a head gasket problem. BZ
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Bruce Labitt Sent: Sunday, April 10, 2011 7:59 PM To: [email protected] Subject: Re: Diagnosing Bad Water Pump, or Heater Core or? On 4/10/2011 7:42 PM, bill zimmerman wrote: > Late coming in on this and have not read other posts but if your problem > came after any cooling system work, hose replacement, etc, make sure you > don't have an air lock in the system, which frequently will result in no > heat from the heater while everything else functions normally. Would not > suspect a water pump problem if the motor is not overheating or signs of > leakage around the pump. BZ > Original problem - overheat - radiator cap let go - coolant everywhere. Replaced cap, added water - trouble ever since. Engine overheats. Could be air lock. How do you get rid of it? I used a coolant funnel attached to radiator cap. Attempted to squeeze hoses... Car is not level right now. Front end is on jackstands. Problem? > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Bruce Labitt > Sent: Sunday, April 10, 2011 7:22 PM > To: [email protected] > Subject: Re: Diagnosing Bad Water Pump, or Heater Core or? > > On 4/10/2011 5:25 PM, Ross Kuhns wrote: >> If the hoses are only a year old, they should come off; >> take a pair of slotted type pliers/grips and you can >> usually work them back and forth a touch as you pull - >> tool is set perpendicular to the pipe/hose. Of course >> don't squeeze too hard, those pipes are soft. If you try >> to confirm flow thru the core, make sure not to use too >> much psi, system doesn't run under too much pressure (what >> 13psi?). >> >> Ross >> >> >> >> On Apr 10, 2011, at 4:34 PM, Ken Bogart wrote: >> >>> I would flush the heater core to verify flow. If its >>> blocked and needs replacement, a temporary bypass will >>> certainly work to keep you on the road. >>> >>> >>> Ken Bogart >>> ----------------------------------------------------- >>> 96 Montego Blue FFS Coldside (His) >>> 97 Black& Tan (Hers) >>> 90 Crystal White (sons) >>> ------------------------------------------------------ >>> http://www.miatacare.com<http://www.miatacare.com/> >>> http://www.cincimiata.com<http://www.cincimiata.com/> >>> http://www.bcchallenger.org<http://www.bcchallenger.org/> >>> MiataMail.com<http://MiataMail.com> list owner >>> >>> >>> On Sun, Apr 10, 2011 at 2:32 PM, Bruce Labitt >>> <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>> I'm trying to diagnose if I have either a bad water >>> pump, or just a clogged heater core. The hose at the >>> output of the heater core has been spliced to insert >>> a GM temperature sensor in the line. [Other than the >>> temp sensor splice, the cooling system is stock.] >>> The GM sensor is reading correctly - it reads cold >>> and the heater line *is* cold. However, at the back >>> of the head, the sensor which goes to the dash reads >>> very hot (after the engine has warmed up, of course). >>> It is as if there is no flow out the back of the head. >>> >>> Things I've tried: >>> 0. Removed thermostat, put housing back. Still >>> overheats. Have new tstat, but have not installed. >>> 1. Remove GM sensor splice, and inspect the inline >>> housing. Can see daylight through the hose >>> connections. Conclusion: temp sensor housing is not >>> clogged and not impeding coolant flow. >>> 2. Added classic coolant flush tee in place of the >>> inline temp sensor. Flushed 12 gallons thru system. >>> Pretty ugly looking coolant, if I must say so. It >>> still does not quite look like clean water, but it is >>> far more water like than before. >>> 3. Put back GM temp sensor. >>> 4. Refilled with water. Installed a burp bucket on >>> radiator, ran engine. Filled bucket 1/3 way. Bottom >>> rad hose does not seem like it is full of coolant. >>> Feels like it is not uniformly hot. Tried squeezing >>> hoses, etc to burp. Not much happened with respect >>> to coolant level. Engine heated up - back of head >>> sensor showed quite warm - heater core loop quite >>> cool to the touch. >>> >>> What I'm going to do next: >>> 1. Bypass heater core. Is there an 'easy' way to >>> get these hoses off? I cut them when I replaced them >>> last summer. Are they 'welded' on by now? >>> 2. Maybe, flush core, if above works. >>> >>> Anything else? >>> >>> _______________________________________________ >>> Miatapower mailing list >>> [email protected] >>> <mailto:[email protected]> >>> http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower >>> >>> >>> _______________________________________________ >>> Miatapower mailing list >>> [email protected]<mailto:[email protected]> >>> http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower > Well, I didn't quite do things in order. I flushed the > heater core. (Pulled heater hoses, attached garden hose > with anti-backflow to one side, attached 6 foot hose to > bucket on the other side.) Nasty, but eventually ran sort > of clear. So it is NOT the heater core. Loads of water ran > through it - it does not appear to be a restriction. No > water in the cabin, either - thank goodness. > > Then I back flushed the head. In the water neck in the back > of the head - out the other pipe to the heater core. > > Hooked everything up again. Filled through burping funnel. > No apparent flow through the core. However, the thermostat > is NOT installed. > > Is the thermostat required for the heater core to get water > flow? > > I have a standard new Stant thermostat. Do I need to drill > out the 'jiggler'? Hole size? Hole is up, correct? > > Is there a good test for a water pump? Looks like I'm > running out of ideas. Carried off 50 gallons of 'water'. > What a fruitless day. > > Got insight? > > Thanks > _______________________________________________ > Miatapower mailing list > [email protected] > http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower > > _______________________________________________ Miatapower mailing list [email protected] http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower _______________________________________________ Miatapower mailing list [email protected] http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower
