Overheating Continues - Page 2

immortal_suby · #16 08-25-2006, 04:44 PM

Quote:

Originally Posted by SSSVX

Did you change your thermostat and see if it made any difference? How did you end up knowing it was your headgasket? When you had that problem, is your temp going up on driving up hills and coming down when driving down hills??

thermostat was the first thing I changed. Also changed coolant. Tried a water wetter. Water pump was new from last timing belt change. Bubbles in the tank proved it was a headgasket. I never did an HC test though.

cbx-man · #17 08-29-2006, 09:31 AM

I had a similar problem once. The root problem was the failing water pump. Coolant was leaking out the weep hole (check that first) and being replaced with air. The air filled that cross over pipe between the halves of the engine. After replacing the pump I un-did the top rad hose and pulled off a heater hose on the left side of the motor and put a garden hose to each side to "pressurize" it and force the air pocket out the rad hose. Cured the problem. I thought it was a head gasket as well, but it wasn't!

TomsSVX · #18 08-29-2006, 09:40 AM

Dan, the reason your gauage is jumpin is because of gases in the coolant... I can almost gaurentee(sp??

) That if you go to open you rad cap a little just after it made a run to red, there would be an enormous pocket of gasses coming out of the rad cap, not coolant.... Same thing happened to the silver... thats why I changed motors

Tom

shotgunslade · #19 08-29-2006, 11:12 AM

Getting much more experience with this phenomenon. First of all, most of the time the temperature gauge sits on the normal position. Acceleration doesn't seem to affect it, nor high revs. The other day I drove from my house to Newark Airport, about 45 miles. Everything normal, until I slowed down and got off the turnpike. Then it started to creep up. Creeps up to red, then suddenly, drops like a stone back to normal. This is the standard behavior, for no reason, it will start to creep up, will touch red, then drop quickly back to normal. Tried to see if anything could make it drop back. At first, I thought taking a tight turn made it drop, because I took a tight turn when it was hitting red, and it immediately dropped. Then, I thought turning the heater on was causing it to drop, because it would start to heat up, I would turn on the heater, then suddenly it would drop. I entertained other scenarios, but the one thing that is common to all, is that when the temperature gauge rises up to the redline, something happens and the temperature drops back to normal. In my experimenting, I was typically doing something or observing something that was coincident with the start of the drop, which was also coincident with the gauge touching the redline. I'm thinking it's not the things I'm doing or the things I am seeing, but merely the fact that it reaches a certain level of overheating and then it goes back to normal. I'm going to have the thermostat replaced as soon as I can get it to the shop.

TomsSVX · #20 08-29-2006, 02:05 PM

Dan, this is exactly what I was experiencing as well. The reason it jumps up is because of an air pocket in the cooling system. once the coolant reaces the sensor where there is extremely hot air, it will drop the temp gauge back down to what the coolant is actually at. These gases in the radiator are more than likely exhaust gases pushed into the coolant through a small leak in the head gasket. Sorry for the bad news and I would still suggest getting it to the shop for a thermostat replacement but I am truely afraid that the worst case scenario is truth and your HG has a small leak and is bound to get larger as time goes on

Tom

shotgunslade · #21 08-29-2006, 02:31 PM

Just hope I can get 2 more track days with it before it goes into surgery over the winter time. Will go ahead and change out the thermostat.

TomsSVX · #22 08-29-2006, 04:25 PM

I drove my silver for 6 months after I realized my HG leak. mine was small just like yours sounds so I think u can get a little more time out of her

Tom

shotgunslade · #23 08-29-2006, 05:04 PM

I just pulled up to the house and the temp gauge was on one of it's little spikes, so I quickly opened the hood, and opened the cover to the coolant overflow tank. There was steam in it. Sounds like your diagnosis is correct. I wonder if this is related to the overheating problems I've always been having to a greater or lesser degree on the track.

Yesterday, it was just fine when I was on the freeway and only spiked when I slowed down. The one time it really boiled over at the track, the coolant was boiling out of the overflow tank. I don't think the engine could have gotten that hot just in the couple of minutes from when I was running at high speed on the track (and temp gauge was fine) until when I pulled into the pits. So, just on the face of it, it would seem the leaking is worse when stress is taken off the engine after a period of high energy running.

My only problem is that the symptoms have escalated. It is now exhibiting this behavior around town. It's getting worse. Will it blow out completely on the track?

Anyone had any catastrophic head gasket failures?

immortal_suby · #24 08-29-2006, 07:06 PM

Quote:

Originally Posted by shotgunslade

I just pulled up to the house and the temp gauge was on one of it's little spikes, so I quickly opened the hood, and opened the cover to the coolant overflow tank. There was steam in it. Sounds like your diagnosis is correct. I wonder if this is related to the overheating problems I've always been having to a greater or lesser degree on the track.

Yesterday, it was just fine when I was on the freeway and only spiked when I slowed down. The one time it really boiled over at the track, the coolant was boiling out of the overflow tank. I don't think the engine could have gotten that hot just in the couple of minutes from when I was running at high speed on the track (and temp gauge was fine) until when I pulled into the pits. So, just on the face of it, it would seem the leaking is worse when stress is taken off the engine after a period of high energy running.

My only problem is that the symptoms have escalated. It is now exhibiting this behavior around town. It's getting worse. Will it blow out completely on the track?

Anyone had any catastrophic head gasket failures?

mine went on like this for years slowly getting more frequent. pulled the engine before it got catastrophic. I suppose eventually it will completely let go or melt your radiator.

TomsSVX · #25 08-29-2006, 07:32 PM

Quote:

Originally Posted by immortal_suby

mine went on like this for years slowly getting more frequent. pulled the engine before it got catastrophic. I suppose eventually it will completely let go or melt your radiator.

Or crack your plastic rad... don't forget, exhaust gasses come with the pressure that pushed it in the coolant to begin with. you can pop hoses or blow open radiators if it builds too much

Tom

SSSVX · #26 08-29-2006, 11:56 PM

what is your mileage now? 90k++? Why don't you do a radiator flush and change out the t'stat and see if it keeps having the same problem...
Will be sorry to see if it's the HG problem. Wonder how much it will cost to do this job...

dcarrb · #27 08-30-2006, 06:15 AM

Just a novice guess here, but if you value the motor, maybe you should consider not driving the car any more than absolutely necessary until this problem is resolved. With coolant boiling out the overflow, nevermind that, as others have mentioned, your radiator is liable to let go (I had this happen on a Legacy), but at those temperatures, you've got one very unhappy engine there. Repeated, hard driving with temps spiking into the red is begging for way more trouble than a head gasket failure.

dcb

shotgunslade · #28 08-30-2006, 06:50 AM

You're right. I'm taking it in next week. Bite the bullet. Do what needs to be done. Fortunately, I'll be traveling next week, so probably can drop it off for a 3 day rest-stop.

shotgunslade · #29 09-07-2006, 01:54 PM

Just heard from the shop. they say it's not the head gasket. Said there was an issue with hoses. (They were only 6 months). Anyway, HC sniffer test negative. No evidence of head gasket problems. We'll see. Watkins Glen a week from Monday

SVXRide · #30 09-07-2006, 02:13 PM

Quote:

Originally Posted by shotgunslade

Just heard from the shop. they say it's not the head gasket. Said there was an issue with hoses. (They were only 6 months). Anyway, HC sniffer test negative. No evidence of head gasket problems. We'll see. Watkins Glen a week from Monday

Dan,

My initial reaction is to question this....everything you've described doesn't appear to point toward "an issue with hoses" -- hoses will either burst or collapse, and 6 month old hoses shouldn't be collapsing....

Looking forward to additional info from the shop.

-Bill