Getting heads machined?

[salsa91]

Hi guys. So I have a quick question. I've never replaced heads before on a gassed.I had cracked heads on my 94 mazda B4. I just picked up a used set and I'm in a really tight budget. Do I absolutely need to get them machined? I haven't even priced that out yet but I'm sure it isn't cheap

Sent from my SCH-I535 using Tapatalk

 

[RonD]

Do I absolutely need to get them machined?

Of course you don't, but...................

What does a set of head gaskets and head bolts cost you?
And what is your time worth?
(once these torque to yield head bolts are tighten, even for 5 minutes, they can't(shouldn't) be reused)

You can visually inspect the heads, look between valve seats that is where the 4.0l's crack, and use a straight edge with flash light to make sure surface is flat(do the same to the block).
If it all looks good then install everything and hope for the best.

Worse case is that you will have to get new head gaskets and bolts again if it starts to leak again.
Well I guess the really worst case is the it leaks and it overheats, which can cause new heads to crack, 4.0l heads do crack if overheated, no do overs with these, pretty much 100% cracking if overheated.

I would check the cost of surfacing at local machine shop, and turn around time, so you have something to compare cost of replacing head gaskets and bolts to, and also you would have to/should surface the heads at that time as well.......because they did leak.

 

[salsa91]

Ok cool. I'll check them out tonight. I'm getting new head bolts with the head gasket kit. I figured if I just wire wheeled it really good and cleaned it up I should be able to inspect them. At first glance they don't look damaged but I'll find out tonight

Sent from my SCH-I535 using Tapatalk