Hi guys,

I just purchased a used 2004 Disco 2 with a supposed blown head gasket for next to nothing. The previous owner stated the car overheated and then there were the typical signs of a blown head gasket - engine misfires white smoke etc.

So I have been reading a lot on these forums about slipped sleeves and cracked blocks which has me a bit concerned. Can anyone share what I should be visually looking for on the block to determine if I may have these issues? I would hate to put it all back together with new parts only to find it was more than just the HG.

i am surprised to see that none of the cylinders have been steam cleaned as they all look about the same. The gasket didn’t have any obvious failure points either.

Any help or guidance you guys can provide would be greatly appreciated.

Thank you.

Kevin B

 

Generally you can't tell much without pulling the heads. Have the heads inspected and machined by a shop. They are prone to warping by a few thousands of an inch, and will not seal properly. The block can also warp. Can be checked with a proper straight edge. Slipped liners can be seen when the engine is torn down and or by a loud ticking caused by the liner moving up and down. As far as a cracked block, hopefully it wasn't THAT over heated. That bites. They are hard to check for while the block is in the truck. Need jigs and testing equipment to pressurize the block and check. Is the engine still together? Does it run?

 

I believe the only way to test for a cracked block is with the heads off. I could be wrong. You can strip the engine then tow it to a shop to have it checked, I don’t think visual inspection cuts it.

Preliminarily, you can test for exhaust gasses in the coolant and pressure test.

I recently did mine (twice due to leaking valve seals that a vacuum test did not catch) and I would highly recommend getting Fel-Pro or another good brand of gaskets, and using ARP Studs. Just my two cents.

 

Thanks for the fast response guys.

I already have the heads pulled off and both the heads and the block checked out fine with the straight edge.

So if if there is no visual way to check for these things I am just going to plow forward and keep my fingers crossed that it is just the HG.

Thanks for the advice on the components. I will certainly use these higher quality parts - I’ve already planned on it based on the hundreds of posts here that say the same thing.

Thanks again guys.

Kevin B

 

I would go ahead and get the heads to a machine shop. Cheap insurance and 3/1000 play is easy to miss with a straight edge. Do your water pump while you are in there. Might consider O rings for the injectors. I would delete the SAI if you are not in Commie-fornia. Several on here will punch me in the mouth for this but skip the $250 ARP stuff and get the $30 stretch bolts. Lucky 8 is your new best friend for this project. If you want to pimp it out then blast and paint your valve covers. Oh yeah, do the PCV mod as well. Get a good gasket set and the 2 O-rings that I could only find at miami british.

 

My 04 had blown head gaskets too (PO replaced them). Except for the erratic engine tick it still runs fine 10k miles later. I tend to believe one reason for the overheating is a not properly designed cooling system. The 03/04 has no engine oil cooler anymore despite the stronger 4.6 engine. I saw oil temps (have an extra sensor for it at the sandwich plate) of up to 240F (longer highway driving at 100F ambient). I consider to install an oil cooler and perhaps an aftermarket oil thermostat to get the oil temps faster to operating temps and hope to extend engine life with that. Another measure is to install a 180 thermostat, but the impact on oil temps seems to be minor, oil temp gets up to 50F higher than coolant.

 

Almost none of this is correct. It is much easier to detect all of this with the engine running. Slipped sleeves will tick loudly at idle once warm, if it is not ticking already you don't have that problem. Cracked blocks are possible but you would likely be getting water in the oil or you would have severely scored cylinder due to the coolant washing the oil off the cylinder walls (you can see that once the heads are off). As far as anything being warped, I have done 7 hg jobs on blown hg's and never seen anything warped. It might be possible theoretically but in practice it is exceedingly rare. I have never had a problem just putting new hg on.

 

I'll add the obvious -

Replace thermostat with lower temp - 180 degree
Dont use dexcool
Install an Ultragauge to monitor temps post HG job - you can even set an alarm with the UG to go off at a specific temp.

My PO installed the lower temp thermostat when he had the HG's done, radiator etc and I've only seen over 200 once or twice while doing 60+ up a steep grade for several mins straight.
its usually 194 max. Avg is under 190.

Good Luck.........

 

Thanks for all of the advice guys. I am a long time Porsche enthusiast (996TT and 951 owner) and have always been impressed by the Porsche community on the forums for help like this. But this forum rocks... it hasn’t even been 8 hours that I made the original post and received several helpful responses already... seems like a great community here...

Thank you guys again!

 

The way to tell a cracked block is easiest while the engine is running and blowing the white smoke/misfiring. Fouled spark plug will be obviously wet and gunky. Using a boroscope usb attachment you can look into the cylinder while the engine is still warm. Pressure in the cooling system will allow you to see coolant bubbling into the cylinder at the seam nearest the block (water passage) between the head and the block.