KADE Head question

[89SiR]

My car recently overheated due to a failed water pump. I reassembled everything only to find that i also had a blown headgasket. Is the aluminum head on the DE prone to cracking, or can i just have the head planed and throw on a new headgasket?

Thanks in Advance,Jeremy

[Ni2s4s0aSnX]

I don't think its proned to cracking, I mean I've heard of them cracking before, but not like its a common thing. If its not cracked put a new gasket on it.

[s13sr20chris]

yeah, put a head gasket on there.

[djsilver]

I changed the headgasket on a 240 this summer. It wasn't as difficult as my V6 front drive Taurus but it was quite a project just the same! I measured the head while it was off and found that the sealing surface was bowed both across and length-wise. My advice would be to check it while it's off so you know the situation. The job of changing the headgasket is too much work to do over because something got left out the 1st time. the FSM flatness spec for the head is .0012" standard allowance and .004" max. Oh yes, measure the block surface as well. It's probably OK but it's worth checking.

Here's my hand-operated garage machine shop method;-After removing the cams, use a straight edge and feeler guages across the cam gallies and get a baseline measurement. (mine were flat)-After removing the head take the same measurement to see if the head bowed up when un-bolted (mine was .004"). If so, that same amount of bow will need to be left in the head sealing surface so that the cam gallies are straight when the head's bolted back down.-Measure the sealing surface across the width and end-to-end. It should be within .002" across the head and .004" lengthwise or the gasket won't be compressed in the middle, between the cylinders.

I had .004" bow in the gallies, .006" across the sealing surface and .010" lengthwise on the sealing surface. The aluminum is fairly soft so I used a 12" single-cut machine file and some machinist's blue to file across the head until it was flat crosswise. That left me with a .016" lengthwise bow! I filed the ends down until it was within .004" lengthwise. When I bolted it back down the cam gallies were flat and didn't require line boring. That's good because I didn't have to re-shim the lifters.

I've been driving the car for about 5 months, tested the rev-limiter several times and done two autocrosses, and it's holding up so far.

[89SiR]

Thanks for the help guys. Everything sounds good, i think i'll just take it to the machine shop Due to my lack of free time to work on it. I'll probably just have the head hot tanked, new valve seals, have the valves seated and have the head minimally paned.

[fullthrtl_tech]

yeah usually those heads can warp prtty good, check it with a straight edge and feeler gauges, if its warped get it machined for a proper mating surface to the deck