no...one is in a 96 z and the other is in a 95 z... I am still thinking it is possible that there is something else going on with your car other than a gasket/warpage issue. Having hope is not always denial..

 

You could be right. It may simply be impeller problems with the water pump. Hopefully there are no warping issues, but I've not had good luck getting one that hot before.

 

Hmmmm. I suppose I'm putting a new waterpump on it either way, so a few hours spent doing that before I strip the entire engine down couldn't hurt.

Even a water pump isn't in the budget for a while either though. I'll remain hopeful though! And possibly stay in denial as well, just as a secondary measure...

 

I agree Eric..but there is always that odd ball miracle exception on rare occasions... I sure do look forward to seeing the resolution to the issue.

 

Scott,

In watching your video I think I see the problem.

You have the hose on the neck of the radiator and the hose just below the neck reversed. The one on the neck should go to the coolant overflow tank and the one just below the neck should go to the water pump or the vent tubes coming from the heads(can't remember where and mine is tore down right now). That is why you are filling the overflow tank up. Hehe, there is the leak. If overheating didn't hurt it, you will be set to roll.

 

I. Love. You.

Ok sorry I missed your call am cooking dinner but will check it out before bed and report back!!!

It's been that way for a year though!?! In other words, when I put the motor back in it last spring I must have flipflopped them? So... well in any case I'll report back!

 

Yes..you are right Eric. Good catch..see miracles do happen.

 

OK so yeah it's official, I Love ACE1252!!!

And the Internetz.

And youtube.

That was an impressive catch, dude, I stood there all day thinking "Why the hail is it spitting all over the place???" and didn't even catch it.

So, we filled it up again and drove about 10 miles with the A/C on and it never got over 180 degrees.

I'm still not sure why it just started acting up though. I put the radiator back in it in March 2009 and drove it all last summer...

But I'll take it!!! Will report back in a few days to make sure it continues to perform well...

 

Yeah, the video clearly shows the line in the wrong place. I guess I should have watched it.

 

Oh sheesh shoebox, you're SO out of my fan club!!! Which sucks, since thus far there aren't any members except ME!!!

And hey when did you become 'shoebox'? Is my old guy memory failing me, or weren't you shbox?

(I don't get out to the Internet much, just when I need something. Just like family!!!)

 

I was shoebox before shbox. Same person. I had to use shbox for my website, since the greeting card company had already used the name I wanted.

In this case, I guess the video was important. No one would have suspected the hose reversal (though, I have seen people do it before), especially after having driven it that way for so long. The hose port in the top of the radiator neck always goes to the recovery tank.

 

OK so it's all over but the crying. Oh wait I did that too. I guess it's completely over...

Ran fine for another 24 hours or so. 30 miles in stop and go traffic in the blistering heat here. Cool as a cucumber, never got over 180. I even ran the bejeebers out of it a couple times, smooth and cool.

Sitting in the drive waiting for the kids to buckle up, it starts idling lumpy and immediately the SES light comes on, and even flashes for a while. I've never seen it flash.

Immediately the temp goes from 180 to the moon. I mean like so fast that I kinda questioned if the gauge was on the fritz again. Straight up to 260. Pulled it into the garage and haven't started it again.

The 'new' code is 300. "Random misfire". So I'm assuming the head gasket gave out and is now dumping coolant into the cylinders?

Also noteworthy though is that it intermittently sets codes 410/1415/1416 to the extent that I've been ignoring them. Earlier in the year it was only 410/1416 and I replaced the passenger side valve, and that helped for like a week. Then it began setting the 1415 too, in addition to the 410/1416.

Only understanding the chemistry of that circuit at a vague level, I'm wondering if it has been getting a small amount of coolant in the combustion for quite a while, and is only now leaking to the extent of failure? Meaning, would the coolant in the exhaust contribute to the 410 circuit being flaky?

I suppose it doesn't matter. I can't count on the car to get me 10 miles so I have to strip it down and evaluate.

I think it's time for go-fast parts. Maybe it failed because it's been stock too long? And we all know how unhealthy it is to leave things stock!

Even the time to read here and do minor troubleshooting with you guys has been a stretch to squeeze into the schedule this past week. A major rebuild is not in the budget or the schedule any time soon.

But maybe I can swing a cam/heads/headers rebuild if I eat PB&J sammiches for the next 6 months?

 

Did you check the coolant level? An air pocket can cause a rapid rise of the temp gauge. Also the AIR pump codes are not going to be caused by any coolant problems. Sounds like those issues were there beforehand. Don't jump to major conclusions without investigation. Look at plugs, check oil for water, do leakdown tests if necessary...maybe even some coolant got on the opti.

 

OK so some new info and umpteen more stupid questions...

The 30ish miles I drove it before it overheated amounted to 4 short trips. I checked the coolant level before I left the drive each time, and it wasn't low until it boiled over. I can't imagine any significant air stayed trapped after 4 heat/cool cycles? But it is possible.

I just spent an hour pulling the plugs. Turns out my massive herculean rippling muscles aren't well suited for this task. But I got them out. They all look perfectly normal.

Also noteworthy is that the car has sat untouched all week, and today when I pulled the radiator cap to look inside (don't ask me why, I just felt compelled to look inside) the cap literally *burst* off, and there was significant air pressure in the radiator, which was half empty. It's an 18 pound (new) so I have to assume it was less than 18 psi ish but that was odd.

None of that explains code 300 'random misfire'. The opti is new GM from last September. When I started it up to back it into the garage, it ran fine. Not obviously missing or misfiring badly enough to sound 'bad'. It sputtered a little on first startup but then smoothed right out.

Another buddy recommended I fill it back up, and pressurize each cylinder individually to see if it bubbles into the coolant. Which would 'prove' a cracked head or blown gasket.

However, the time I've spent now thinking about it and flirting with it I could have pulled the motor and stripped it down entirely. I think I may as well do so at this point?

It would seem a decent used set of heads runs about $200 on ebay at least. I haven't checked racingjunk.com yet. I'm watching this set:

http://cgi.ebay.com/ebaymotors/ws/eB...id=p2759.l1259

but I don't have the cash to spend anyway.

My other major concern is any other possible damage to the lower end? Meaning, should I just rebuild the entire damned thing with 125k on it? Not that a full rebuild is in the budget either. I'd be stretching to do used heads by August. Still no signs of coolant in the oil.

There is also the (grit your teeth and prepare to cringe) magic fix block/gasket sealer stuff. I used it in my old van last year, which was clearly smoking white and getting coolant in the oil, and I put $20 worth of that block seal crap in it as a dying hope, and I got about a year and a half out of it after that, never smoked again and the oil stayed clean. In fact the van died of other natural causes with the engine still running fine. That was a TBI 350 though and I'm not sure what the compression was on that motor but it's not even close to the LT1.

Already paid the rent so too late to spend that.

Going to shine up the van tomorrow and take it to the Pilot Mountain Cruise. Just won't be the same without the car, but I have to admit the one we went to last weekend in the van was a much more comfy situation!

 

If you had pressure hold for a week I would say that you do not have an internal coolant leak. I would try filling the system up and bleeding it again.