What are some symptoms of a cracked Magnum cylinder head? As far as how the truck will run, etc. I was looking around but did not find anything that was real descriptive.

 

here are a few... overheating, water in oil (milky white stuff), oil in coolant, coolant or oil leaking from around head area . blown head gasket can also do all of these. rusted freeze plugs can also leak coolant around the head and block.

 

I pulled my plugs and they were pretty full of gas indicating a rich condition. However I do not see anything anywhere that would cause it. Could that possible be it?

I was also going to try aleak downcheck. My thought is if the head is cracked I will have a high leakdown %age.

 

A misfire is a sure fire symptom.

 

are you saying the plugs are soaking wet with gas, as in super rich fuel ? i can't think of how a cracked head could lead to that. i would think super rich would be more likely a bad o2 sensor telling injectors to richen up, or maybe a leaking/messed up fuel injector thats overpumping fuel. just my best guess.

 

Missfires and pinging that can be traced to one cylinder, especially cylinders number 7 and 8, the rearmost ones.

The standard factory air to fuel setting at wide open throttle is 'super rich' at about 11.5 to 1 air to fuel ratio. If you make a few wide open throttle runs before looking at the sparkplugs, expect them to read rich, it is 'normal' as is black soot on the inside of the tailpipe. (Dodge sets the a/f rich to protect the catalytic converter from overheating at full power)

An cylinder leakdown tester is the best way to look for heads cracked bad enough to penetrate the water jacket.



http://www.area51groupllc.com/produc...products_id/30

 

+1 for the leakdown/compression test.

I had a #5 Misfire for a while (common, there are a bunch of threads on it). Replaced all the typical stuff thinking it was a simple tune up issue, bad wire, blah blah..

After the condition worsened and it was running rougher and rougher I did a compression test. #5 was WAY low, and when I put air on it I could hear air coming out the pipe, etc. Tore it down to find a nicely bent exhaust valve.

The moral of the story was that a new set of Magnum HD heads fixed *that* issue. Now I am backtracking a few other things, trying to find out what may have lead to it (ie, running lean due to a handful of things)

You can rent a comp. tester at Autozone and run it yourself. Screw it in the hole you think is bad (or all of them for complete confidence), unplug the coil wire and crank it over a few times. Take down your readings and see if you have 1 cylinder thats lower than the others by a significant margin.

I think mine averaged 130 or so on the "good" holes, and like 40 on the bad guy.

Good Luck!

 

+1 on the compression tool. Go ahead and rent one of those things, it will definately tell you if its compression or not.