Unfortunately, I can't just push it off a cliff since it isn't mine. He has a mid-90's Tahoe with the 350 Vortec. It has an unexplained loss of coolant. No leaks of any kind, not in oil as far as I can tell, but gone none the less. I was assuming he probably had a bad headgasket which was allowing cylinder pressure into the coolant system, and pushing the coolant out the resevior, but I just talked to my brother, who has a Yukon, and he said he had the same problem. I will tell you what my brother said, and see if we can figure this out together. My brother couldn't tell the difference between a spark plug, and a brake pad, so it's kind of spotty. He took his truck to a shop. The manager of the shop had been a service rep at a Chevy dealership for 15+ years, and told him... "All the 350's do that after 10 years or so. I know exactly what it is without even looking at it. The #6 valve gasket is bad. Put some oil treatment in it, and keep the coolant at a good level until you can bring it in. It will be about $380 to fix it." Keep in mind that this is hitting my ears as a third party. I assume the guy was talking about the intake manifold gasket. What do you guys think? Anyone know a good place I can get some info on it. I doubt the guy will be quick to tell me exactly what is wrong knowing I'm not going to bring the truck to him. Brandon
I helped a friend with his Chevy once. My car was 10% slower on the way home. Who says our cars don't have a mind of their own? Grady
Well ..... this (breaking down) is called "the bowtie effect". The whole "#6 valve thing" I don't understand. Do a compression test. Does it show any signs of white smoke? Could be a head gasket. Could be an intake gasket. Or possibly even a minor leak somewhere that you haven't checked. Oh yeah .... check & make sure there is no coolant in the oil! (it would be "milky" if there was)
Pressurize the system, go to you local jiffy lube or service station and ask them to pressurize the system with a radiator pump.. It will whistle where it is leaking.
Well, I found it. The heater core line comes up, and goes into the front of the intake manifold. The actual joint there is kind of hidden from view. I noticed what looked to be a little bit of coolant stain where the passenger side valve cover, and intake manifold come together. I reached over and grabbed this line, and it came out in my hand. The steel connector on the end of the hose was completely eatin away, and it snapped right off, leaving the threads in the intake manifold (This after only 68k miles). I went to the dealer, and showed him the piece I still had, and he knew exactly what it was, and said it happens all the time. The crappy thing about it was that the threads were so soft from rust that I couldn't get anything to "bite" to get them out. I ended up running a tap the same size as the connector down through them. It put some metal in the coolant system, but it needed a flush anyways, and it got the job done. Where the coolant was leaking, it was running down the seam on top of the valve cover, and the heat from the motor was making it evaporate before it could get to the ground. Yeah, the Chevy thing was my first response as well, but what are you gonna do? You can't control the type of vehicles people buy. It's funny though, I took the key back to him this morning, and he asked me if I thought I would have a chance to look at his Camaro (94 Z28 vert). Something about the heater not working, and a check engine light. His old work truck is around a 93 F-150 step-side though . Brandon
Stay clear!!! (that Camaro) I hate those cars. My fiance had one not too long ago. What a piece of ****. Just hope it's not the heater core in that car ..... you practically have to rip the whole dash out to get to it ......
Yeah, that's exactly what it was. It could have been worse though I guess. He could have had to get the entire line. I had a little rubber elbow tear last weekend that connects the PCV valve line to the back of the intake manifold on the 5.4L Triton. I had to get the entire line with valve from the dealer for $39.99 + tax. The steel disconnect on the neighbors 350 was $15. Go figure. Brandon
