testing head gaskets

[sleeps]

wanted to double check my head gaskets. my dad bought the EDAS and put it on my 05. it has went off several times but with no signs of blown head gaskets. so i got napa's compression test kit (the one with the blue liquid) and it checks out good. didnt change color after trying two seperate times today. i cant find a 15psi gauhe anywhere near me to do the other test. should i order one and do it? anything else to check? or do you think im good with assuming my gaskets are fine?

[Tuscany]

You seriously bought that "engine damage avoidance system" from that douche bag bill HUIT? Send that pos back and get you money back that guy is a moron.

[PowerStrokeEnginuities]

Bug a liquid filled pressure gauge. 20psi is fine too.

[ZMANN]

most home depots etc have the low pressure gauges for testing gas lines etc

[snafu!]

Originally Posted by Tuscany

You seriously bought that "engine damage avoidance system" from that douche bag bill HUIT? Send that pos back and get you money back that guy is a moron.

[sleeps]

Originally Posted by Tuscany

You seriously bought that "engine damage avoidance system" from that douche bag bill HUIT? Send that pos back and get you money back that guy is a moron.

dad bought it :/

he was over-cautious seeing as i was 1300 miles away. i have seen alot of bad things said about him. its pretty much just a pressure sensor setting off a speaker set to 16psi right? could he really screw up that bad and it be that much of a P.O.S. ?

[sleeps]

Originally Posted by ZMANN

most home depots etc have the low pressure gauges for testing gas lines etc

thanks, ill check there tomorrow. i drove to several hardware shops and autozone/napa and nothing. harbor freight only had a 0-7psi and the next was 0-160psi.

[bismic]

The Lisle LIS20300 pressure/vacuum gauge will work (I believe it only goes to 14 or 15 psig though). O'Reilley's sells it.

Also - OTC 5613 Vacuum / Pressure Gauge Kit (0-15 psig)

Also - I believe Harbor Freight sells one.

Mityvac sells a 0-30 psig gauge and also does vacuum. It would be ideal: MVA6181
Mityvac
http://www.ntxtools.com/network-tool...Y-MVA6181.html

Lastly: KD Tools (0-15 psig) Model# KDS2521 and Actron CP7802 (0-15 psig)

The best way to check to see if combustion gasses are getting into the coolant is to drive it and get the coolant up to normal teperature (and it will be fully expanded at that point).

Shut it down and wrap a towel around the degas cap, and then remove it (slowly and carefully) to vent off the pressure. Then re-install the cap.

Then drive it and watch the pressure on the degas bottle. Any pressure you see at that point will come from gas leaking into the coolant, and not from the liquid expansion of the coolant.

[lenzhotrod]

Not completely correct, at higher temperatures pressure will begin to build even with good gaskets. Remember, pressure stops boiling, If it still has a EGR cooler intact it will try to boil the coolant.

[bismic]

Originally Posted by lenzhotrod

Not completely correct, at higher temperatures pressure will begin to build even with good gaskets. Remember, pressure stops boiling, If it still has a EGR cooler intact it will try to boil the coolant.

Sorry but you are not completely correct Len. Besides being thermodynamically sound, it is proven on my system (and others). I do agree that you might see 1 psig increase (the volume/space increase due to any amount of "flash boiling" on a healthy EGR cooler surface is minimal), but that is all a normal system will produce.

Any appreciable boiling is prevented by proper heat transfer (which includes proper coolant flow) and the physical properties of the coolant. You need adequate contact time on the heat exchangers surface to flash boil and a healthy system just does not have much.

That being said, yes I can see where it is possible that SOME systems operate at temperatures high enough to flash boil more than a minimal amount of coolant on the walls of the heat exchangers, but even then (in most cases), the vapor will recondense as it mixes with the mainstream coolant flow.

I run the SRL+ tune and I get essentially no pressure build after doing the described procedure (1 psig is not enough to cause concern).

Lastly, pressure does not stop boiling, it simply elevates the boiling point. Normal back pressure only elevates it 15-20 C degrees IIRC (25 - 30 degrees F). That is not enough to drastically effect the design of heat removal from the EGR cooler that sees exhaust gas at 700 *C (1300 *F +). Remember, our systems are degas systems, not pressurized liquid systems. The normal pressure that our system operates at is less than 10 psig (8 psig typically) and not the 16 psig setpoint of the cap.