High RPMs, Radiator Hose Blowout!

[OneBadTT]

I just finished fixing my MAF problem and decided to take the car to get it inspected. The car, in park was running 2800- 3200 rpms. Within 2 minutes, the radiator over flow started bubbling up and over, then the radiator hose on top exploded and blew a 2" hole through it. The inspection shop wasn't too happy about the antifreeze everywhere.

Does anyone have any idea what happened? Had to have the car towed home and now I am going to fix it. I just don't know how to make sure it doesn't happen again when I make the repairs. Tested the thermostat- it works fine in hot water.

 

[bison]

Compression entered the cooling system and over pressurized it causing the hose to explode. You likely had a lot of detonation at some point recently and hurt the head gaskets.

 

[OneBadTT]

Does this mean the head gaskets have to be replaced? I haven't tried that before. Is it hard to do?

 

[bison]

Does this mean the head gaskets have to be replaced? I haven't tried that before. Is it hard to do?

Most likely yes and its not that hard to do if your used to wrenching.

 

[OneBadTT]

Thanks Bison- Is there somewhere that the step-by-step procedure can be found? Are there any special tools needed? Thanks.

 

[Red C5]

Not a tough job to do but takes a bit by yourself. I'd verify that it's the head gasket but I think more than likely it is.

 

[TurboBuRick]

Are you sure your cooling fan working?

 

[HighMileage]

Wouldn't the rad cap have vented that pressure off into the overflow bottle?

 

[Razor]

Perform a compression test before tearing into it.

 

[charlief1]

Thanks Bison- Is there somewhere that the step-by-step procedure can be found? Are there any special tools needed? Thanks.

Send me a PM. I'm just south of you in Hillsboro. I'll be more than happy to help you if you need it.:smile: You need to do a compression test and a leak down test at the very least. You can get the tools at AZ on the loan a tool program. If you want I will give you my number and will walk you through it.:biggrin:

 

[OneBadTT]

That would be awesome! I appreciate it. I'll plan to get the tools and then I'll contact you. Thanks, this will be the first time I have taken my engine apart and I really don't want to screw it up.

 

[charlief1]

That would be awesome! I appreciate it. I'll plan to get the tools and then I'll contact you. Thanks, this will be the first time I have taken my engine apart and I really don't want to screw it up.

Not a problem. Just send me a PM when your ready.

 

[OneBadTT]

Update:

Part of my problem turned out to be the fan (thanks TurboBuRick). The wire harness damage to the grounds created a number of problems, including the fan relays not working. When I repaired the wiring and installed a ground kit I forgot to check the fuses. I found the fuse blown and replaced it. The fan works fine now and I haven't had any overflow since then. I am still having high temps though, even with a new thermostat. I have tried to work with the IAC and TPS to get the RPMs down (now running about 1600 in park) and the IACs up (still running "0" in park) but no luck. I have ordered a new IAC valve. I cleaned the old one well, but it didn't help. No code reading now either.

Charlief1, I still haven't worked at testing compression but I will let you know when I do.

Taking it back for an inspection this morning so wish me luck. I know the inspection station will be happy to see me...

 

[SCOOBY DOO]

The engine is overheating. With the engine cold...start it up with the rad cap off...and ensure when the thermostat opens that the water in the rad is circulating. If your rad is old...it's likely clogged. I've seen alot of cars come in the shop with rads so clogged that very little water is circulating.

 

[Razor]

To setup iac close the throttle blade by unscrewing the blade screw so that it doesn't touch. A closed throttle blade will give higher iac readings not zero
Just make sure after the blade is fully closed to set tps to .38-.46
Reset computer by unplugging connector by battery
Start engine and watch iac readings
If your still at 1600 you have a massive vacuum leak.

 

[NorEaster]

Blm

What are you seeing for BLM?

Sounds like a vac leak maybe?

 

[OneBadTT]

Thanks everyone,

Well, I failed my inspection again. He told me my RPMs were too high. On the way back from the Inspection Station I stopped and bought a vacuum pump tool. I'll have to read up on how to properly check vacuum, but I played around a little and I tried to pump the vac hose that comes off of a "y" to one of the hard lines that goes to the block- no pressure measured at all. I don't know if that is normal or not.

ScoobyDoo-I started the car up with the rad cap off- the fluid in the rad is circulating well.

Razor- I'll try that- I haven't tried to disconnect the battery cable.

NorEaster- My BLMs have been running around 118.

 

[charlief1]

If it's an 86 your car will be considered an antique in January so all it'll need is the safety inspection.

 

[OneBadTT]

Razor- I tried what you said and it had no impact. The IACs did go up but as the car sat in park, running, the IACs decreased to zero and stayed there. I think I am going to change my chip out to the stock one and see if that helps. If not, then I am going to start searching for the vacuum leak.

Charlief1- I wish it was an 86 right now, but it's an 87. :frown:

 

[HighMileage]

What does your PowerLogger show in the 'Prog Idle' box? It's the one under the IAC Counts box.

As far as a vacuum leak,I replaced my 23yr old hoses after finding some that were attached,but were more partially stuck on,than properly attached. Many looked good on the outside,but were hard and crumbly.

Got new ones from nos4gn.com. Under $4 for 72 inches of each size. Shipping was faster than a speeding bullet.

Have you done the carb cleaner spray test for vac leaks? Do you hear a hissing sound at idle?

The 1,600rpm idle is indicated on the PL and not by the inaccurate factory tach. ?