These heads are prone to cracking, but that's not to say they definitely will crack. He just trying to sell you on the new redesigned heads to prevent issues down the road.

 

If they never get overheated again what's the chances they will crack?

Looking back i would have totally bought new heads. There was a set on ebay for 350. So far im at almost 300 withparts, solvents/tools, machine shop labor, and uber cabs to the shop and back. Plus the hours and hours ive put into messing with them.... Hind Sight is 20/20 as they say. I just didnt know you could buy new ones for so cheap.

 

I may have messed up... I was cleaning the the caked oil and sludge off the top of the engine block and some of the camshalft rollers spun in their sockets. I was reading later that these need to be going in the same direction during assembly. The manual says there is a mark signifying what edge should face down . I cant find it. On a scale of 1-10 how effed am i? Will these break from reversing direction?

 

They won't break but they will wear faster if the direction becomes reversed.

 

got a call back from the machine shop- they say it needs hardend seats.
What's this new reinforced cylinder head you speak of and where do you get them?

 

You just can't catch a break, can you?!

 

it certainly feels that way.

 

old design





new design






as you can see there is a lot more steel between the cylinders in the new design...

I got my at Clearwater Cylinder Head...there is another in my area here called Odessa Head..
they are on ebay too

 

FYI, There are no new 3.9L heads for sale on eBay unless you want to pay at least $470 for the pair.
http://www.ebay.com/itm/151031535162?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
Here is a remanufactured one that is the newer design. They'll cost $320 for the pair plus 50 bucks or so for the shipping. That's about a 100 bucks less than the new pair.
http://www.ebay.com/itm/261815287253?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

I have the "new" design already. so I guess that's a plus. Got the heads back today and the paint is drying. (want to easily see any leaks should they occur) - installing tomorrow.

Question for you guys - I did a total space out rookie thing today while tying up my rear brake job. I tried to bleed the brakes with the drums off - doh! took me awhile to realize my dumb mistake

both new brake cylinders appear to be leaking. Are they broken or just leaking the last bit of seepage from being over stressed? or will they be fine?

I really don't wanna take them efffin-mafakas apart again but I guess if I have to I deserve it for doing something so dumb... that'll teach 'em..