Monday, January 22, 2007

Bad Dreams

I had a dream last night. I had parked SoDak in a light industrial area by a scrap yard. This was so it was out of the way until I had time to fix it. When I came back a month later, someone had taken the hood, fuel pump, injectors, head, turbo, etc. I was furious, but sort of relieved because I didn't have to fix it.

Sunday, January 21, 2007

Headgasket

Well, looks like SoDak has a blown headgasket. Someone, who shall remain nameless, drove the car for an unknown period of time "in the red" on the temperature gauge about a month ago. I thought it would be OK, but evidently it is not. Symptoms...
  • When starting the car, coolant reservoir pressurizes even though the car is not warmed up.
  • Loss of coolant with no coolant leaks
  • Difficulty starting (it still starts at -5 F with no block heater)
  • Faint odor of ethylene glycol (coolant) in the exhaust
  • More white smoke out the tailpipe that usual
  • RPM-dependent heater output (my guess is that combustion gases are entering the cooling system and preventing it from functioning normally)
  • Periodic slight increases in coolant temperature (temp has always been rock-steady, again, gas pockets in the cooling system preventing proper cooling)

The definitive test for a blown head gasket is to test for hydrcarbons in the coolant reservoir using an exhause gas analyzer. Notice that coolant/oil mixing is nowhere on the list. Coolant oil mixing is NOT diagnostic of a blown headgasket as the oil cooler on this vehicle is liquid-cooled and is part of the oil filter assembly. The owner before the owner before me (a professional Volvo mechanic from Sweden no less) tore off the head to repair a "head gasket" and found that it was just fine and that the oil cooler had failed, a very unfortunate mistake...

Tuesday, January 16, 2007

Heat Contd.

I pulled both of the heater hoses off of the firewall (after I clamped off the hoses). These go straight into the heater core. I shoved a hose in there and flushed it completely, from both directions. Water flowed freely. This meant that I did not have an issue with the valve or the vacuum switch or blockage in the core. I hooked it back up and "bled" the cooling system (to get out any air bubbles). It seems to work much better now, but heat is still somewhat dependent on engine RPM. Possibly I need to replace the thermostat. It may be stuck. We'll see how it runs this week.

Sunday, January 14, 2007

The Heat is On (well, actually it's off...)

I appear to have lost about 90% of the heat in SoDak, just in time for winter finally showing up! The problem is most likely one of three things.
  • Water valve (allows coolant into the heater core)
  • Water valve vacuum switch (uses vacuum to open water valve)
  • Heater core (the water to air heat exchanger)

It is unlikely that the problem is the heater core as this problem came up rather suddenly. Fortunately, I have Martin Luther King Jr. Day off school and will spend it at The Foreign Service trying to get heat.

Wednesday, January 10, 2007

Dave's Volvo





Well, SoDak just keeps on chugging along so I guess I have to live vicariously through other Volvo owners. Dave is rebuilding his D24T and is looking for some serious power... He used a stock headgasket and stock headbolts. I'm very jealous of his squeaky clean block. Here it is with its guts removed. And now they're back in!

Something I definitely don't have the courage to do- take apart my turbocharger...

He's shooting for 140 hp :)