New head, plus problems. learn from my mistake

[einekatze]

I have recently repaired a 2001 Daewoo Nubira SE 2.0 DOHC. The job started as a simple diagnostic and turned into a job taking up the last six months of my free time. The initial symptoms this car had was a whining upon start up, very similar and easily mistaken for a screaming power-steering pump, which the owner continued to drive on thinking it was so. The car developed a loss of power suddenly and then completely quit on the owner. All electrical items continued to work, including the starter, with no avail to starting the engine. The verdict on the failure was a, by this time, completely destroyed idler pulley within the timing case.The idler was actually so bad there were scraps of mangled plastic throughout the cam gears. Being that this is an interference motor I was instinctively worried, but due to cost constraints, replaced just the pulley and timing belt, reassembling the timing case (as the motor mount goes through the timing case) and hoping for the best. No sympathy on the first fix, and my fears were confirmed by a compression test. The valves had been bent beyond reasonable tolerances, and a new head had to be ordered, along with every gasket on the upper end and new spark plugs. Four hundred and sixty dollars in parts later and 6 hours labor in, the car now had a new head. The car ran for a week like a Swiss watch, then suddenly developed a very nasty coolant leak, and in order warranty my own work I demanded the car not be driven untill I fixed this issue as well. The car was leaking quite regularly from the water jacket on the passenger side of the intake manifold. I was fairly sure this was due to worn bolts and mating surfaces that were not flush. However, there was obviously some pressure issue that forced the simple aluminum seal to fail. Being that the coolant pump bearing was very solid and the was no moisture in the timing case, nor a drip from the bleeder hole in the pump itself, I did a simple thermostat check and found it had malfunctioned. I am really not sure why you cannot buy the thermostat alone for this model Daewoo, as it does come out of the housing, however, there seems to be a conspiracy to make us buy the entire housing.
Let us review here. We now have a brand new top end, with fresh Felpros all the way round, and a fresh thermostat. Before wasting time, labor and RTV on the leaking return jacket, I decided to see how the leak had changed.The leak had slowed to an off beat drip, however there was now coolant leaking from the timing cover. The point of least resistance had now moved to the Worn, but previously functional coolant pump. At this point I being to rip my hair out, knowing I had to enter the timing case once again. Two of the three coolant pump mounting bolts (t6) had been stripped out previously making the already tight space constraints more difficult as an easy-out is now in order. To add insult to injury, the water pump had welded itself into the block and required a ten pound crow bar to budge. The new pump went in smooth, sealing well with no leaks. Being well aware of the labor involved in breaking into the timing cover, I ran the car with it off (attached the motor mount skipped the cover) whilst I bled the air out of the coolant system and heater core. The heat had actually become better then that of my 09 Chevy, for as much as that pains me to say.
At this point I begin to celebrate as the car has been running for forty minutes with no leaks. I decide to reassemble the vehicle, including the 14 7mm bolts in the wheel well, and set her down. She ran well as I let her idle before the first drive after this repair, but as soon as she had been driven a mile she developed another ugly leak, though I felt it was not the same leak as before, as the point where the coolant ended up was not consistent with the last leak. The engine light came on upon the next start up and was revealed as a multiple random misfire. I brought the vehicle back and preformed a pressure test on the coolant system. A new leak has developed in the return line that runs under the intake manifold. This is actually amazing news compared to my initial fears, that because the coolant system now had proper pressure, as a new car would, that the rear of the head gasket had now blown out.
Being that it is now quite cold outside I decided to add extra coolant as the level had dropped so much once again. After adding and starting the vehicle, the misfire code had gone away. The hose was replaced and the misfire code has yet to come back. The moral of this article I suppose, would be to continually check the weakest component of the system as problems develop or persist, and never buy a Daewoo. The only thing I have ever know them to make was a stereo, and not even that remained original in this car. I hope this may help and amuse many of you on this site and if anyone has some information on a thermostat for this car that is sold without the housing, please do not be afraid to private message or an E-mail regarding the subject. Enjoy and good luck fellow Daewoo mechanics.

[benzino]

good work hahaha

could have done with some gaps in the text though

and i don't think you can tell people on this forum not to buy daewoo... it's too late

[Puddle31]

i dont' know where you are, but in the states you can buy a thermostat without the housing. when my plastic housing broke, i went to Pep Boys, the auto parts store and asked them for a thermostat for a '00 Lanos. That was all the had, the thermostat. I took it out and did some jury rigging and got home, and then had to order the housing and the thermostat. I got the metal one so I won't have to go through that again. That suggestion came from the guys on this site.

i am sure you can order just the thermostat. they had them in stock in the store.