overpressure in the surge tank ?????

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overpressure in the surge tank ?????

Postby junglehummer » Mon 03 Sep , 2007 1:10 pm

hello everyone, im having a problem with losing coolant out the surge tank cap vent line. i just replaced the cap, with a 16lb., and it still spews coolant out, and the temp guage says its cool[190] . anyone had this problem?? its a 98 turbo d.
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Postby Dan Neuroth » Mon 03 Sep , 2007 3:41 pm

Might be a blown head gasket or cracked head and it is over pressureizing the system ??
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Postby h1sp » Mon 03 Sep , 2007 9:18 pm

What were you doing before this happened?
Long Trip?
Did the Truck over heat?
How long after its running before the coolent spews out?

1. Try the test where first thing in the morning you open the thermostat cap up then put it back on.
2. Start the truck for 1 minute then turn it off.
3. Open cap again to see if there is any pressure.

Should be NO pressure.

If Pressure:
How about a co2 test ?
or cyl leak down on 7 and 8?
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Postby junglehummer » Tue 04 Sep , 2007 8:03 am

weeks before i was climbing out of my property, and coolant spewed out. i took a look, and my surge tank had split 2 small holes in it. ordered a new tank, replaced it, and sure enough miles later my coolant light came on. for a week or two, it seemed as if i was losing coolant and could not find out where. i assumed it was leaking into the motor. i was taking it to a mechanic, and had my wife follow me. as we were climbing out of the property, she saw coolant spewing from under the truck. i imediatly thought it must be a leak at the hoses, and was happy it was not an engine problem. the next few days were trying to see where the leak was coming from, and everytime i got out of the truck to look, it was drying up fast. after changing tank cap, same thing.so, a blown head gasket, or cracked head can cause these symptoms, even with no water in the oil, and the truck runs great?? i was wondering about the water pump also. ive been dealing with this problem for over a month now, the problem is im in costa rica, and good mechanics are hard to find. and here, they will all tell you they can fix anything, but cant even keep theire own cars running. gotta love this 3rd world livin!!
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Postby Axleman » Tue 04 Sep , 2007 8:35 am

Yes, you can have a blown head gasket and the truck will run fine, no water in the oil, etc. Mine did for months until it got so bad it couldn't keep coolant hardly at all.
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Postby humvee1025 » Tue 04 Sep , 2007 4:20 pm

What I would do first is when the engine is cold put a coolant pressure tester on the surge tank to about 16 psi and see if it holds. If you're loosing pressure and no visible coolant leak I would start taking off the glowplugs starting from the back #7 & #8. Where are you in Costa Rica? I go there once in a while. Let us know what you find out.
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Postby chuck » Tue 04 Sep , 2007 5:00 pm

First I'd check to see if your water pump isn't leaking. There is a little hole on the water pump behind the pulley which will leak when the seal is gone.

Next I'd check for a cracked block or head gasket.

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