Heater core coolant hose melts.. any tips?

[scotty]

Today, for the second time, the heater core hose has melted. First time I was able to drive home and chop away the melted part. Today, the same thing happened, I was on my way home then the engine shut it self of, probably due to it got so warm it couldn't get any spark(the coolant temp was normal all the way, would of course stop car if it started to get warmer, but it stayed within normal range, so I thought it would be ok to drive a short distance).

So had to be towed home. I hope, and think, that there is no damage to the engine, and turbo.

Anyway, to what I'm wondering about.. it's this hose: http://www.ma70.com/bishop92t/techtips/7mlayout1.jpg (left side in picture)

Has anyone ever experienced the same thing? How can I prevent this hose from melting? It's not touching anything, i.e. valve covers, firewall..
It melts just above where it's mounted on the block.

Sorry my bad explanation (and most likely stupid question)

 

[hvyman]

Where is it melting at?
Do you have EGR?

Check the gaskets on the egr cooler or on the block off plates. Cheap gaskets will leak.

 

[scotty]

Just took a picture.

Don't have EGR/cooler etc.

 

[hvyman]

Interesting.

You should still have egr block off plates at the back of the head.

Where did you get the hose from and how old is it?

 

[scotty]

Yeah I've got a block off plate.

It's OEM, took it of my GE engine when doing the swap. Used it on the GE engine with no problem, it doesn't seem rotten/old either.

 

[joel903]

Time for you to get the Mishimoto oem replacement silicone heater hose set.

 

[IJ.]

NOT "melted" that's an overpressure burst....

 

[shaeff]

NOT "melted" that's an overpressure burst....

Agreed. Looks like the coolant got pretty hot and caused pressure build up. Time to find the leak, whether it be a pinhole in a hose, or a BHG. I suggest getting a UV dye kit and putting that in your radiator. Drive for a bit, then park in a dark area and find the leak with the detection kit. Tracerline FTW!

 

[IJ.]

Personally I'd be looking at another possible cause starting with a B and ending with a G seperated by an H

 

[TurboStreetCar]

What radiator cap are you using?

 

[scotty]

If it's a BHG I might just sell it as it is, I'm tired of having so much problems. Been working on it for 5 months, and driven it about 3 weeks. I changed the HG and used APR studs(with right torque) before putting the GTE engine in the car. Been using it for about 1 week after doing that.

What causes overpressure?

I'll try to use a UV dye kit.

I'm using a OEM cap. Fairly new.

I've checked the dip stick and oil cap, nothing "milky" or anything.. is there any way to check for BHG at this stage? compression check?

 

[jdub]

A BHG will cause combustion gas to enter the cooling system - that can cause an over pressure. Do this:
- Get a NAPA Block tester to check for exhaust gas in the coolant
- Look for bubbles in the coolant overflow bottle with the car at ops temp - they will be coming out of the rubber hose attached to the cap
- Do a compression test

Did you use an OEM HG or MHG?

That hose could have been bad and never show it just by looking at it. Replace it with an OEM hose and monitor.

 

[scotty]

Thanks for tips.

I used a OEM HG.

I'm ordering a new OEM hose tomorrow, going to take it for a ride with it and check if there is a BHG.

 

[grimreaper]

bad thing is with no coolant (or low coolant) the gauge isnt actually reading temps properly. A motor seizing from an over heat will need a full tear down. You may get it started again but I'm betting $$ compression will be down.. Hopefully it's not this bad, but there aren't any overheat/low coolant shut off safeties on the 7m.

I get a light & steady stream of bubbles in the res. after some heavy boosting or hot days with lots of stop and go. Only symptom too. Still cant get any tests to register the motors hurt.. (leakage,compression,block tester etc..)

 

[scotty]

Just changed it with a silicon hose. Drove it about 15 mins. Nothing too noticeable. Checked overflow bottle, there was a lot of bubbles, so that's not a good sign..

Going to check for exhaust gas in coolant within next few days..