aluminum or cast iron

[donlightbody]

probably a dumb question, are the heads (2.9) aluminum or cast iron? trying to figure what they'll cost me at the salvage yard. any tips on [/PHP]what to look for when picking a set? Hope to find 89+ as those are the redesigned ones right? Think I just have a blown gasket (water in oil, not checked compresion yet) but if they've got to come off I'd might as well be ready. Thanks guys.

 

[4x4junkie]

Iron

 

[Psychopete]

Iron

+1

Search!

I have NEVER seen the better heads on an '89 (much less an '88) unless they were swapped on.

Infact I've had THREE '90 engines and they didn't have them either.
The heads are most ewasily identified by the threads of the bolt hole in the END of the head where the alternator bracket mounts, the early heads use 8mm threads, the later, better heads use 10mm threads.

For all practical purposes you need to find a '91 engine to find the
better factory heads.

BTW, 2.9's don't blow head gaskets.
They crack heads up in the rocker area.

so a typical machinist looking for cracks in the combustion chamber will usually find nothing.

AD

Pete

 

[donlightbody]

thanks for the replies, I haven't had much time lately to really research anything. Don't know if it's a gasket or cracked head. It's NEVER gotten hot but a couple months back after flushing the coolant system the coolant started into the oil real bad, the level would drop about a half gallon in about 5 mi of driving! Barrs stops leak has stopped it almost completely. Gonna check the compression today and see what that looks like. I really don't want to have to go find heads, but if I do, looks like I need to find a 91 then. Thanks

 

[AllanD]

The Newer heads have an '89 part number, but that doesn't mean they were
installed in any 1989s, infact you'll find a lot of 1990's with the earlier heads.

The engines were built a long time in advance of vehicle assembly.

The difinitive way of indentifying them requires removing the valve covers

But almost as good is to unbolt the alternator bracket.
If the bolt that goes into the head is 8mm the head is early.
Later heads used a 10mm bolt.

AD

 

[Loanranger]

I know I have read on here a few times that the way to tell early from late heads was to look at the valve cover. If the valve cover has a lip that sticks up, it's a late head, if it sticks down, it's an early head. Is this the wrong info?

And btw, if you search "2.9 heads" on this site, is comes up with nothing because 2.9 does not fit the search criteria being less than 3 letters. Yeah, the search function sucks because of this.

 

[hidesertrat]

See if this helps.....it did me.

http://www.therangerstation.com/tech_library/2_9_Page.html

 

[Psychopete]

And btw, if you search "2.9 heads" on this site, is comes up with nothing because 2.9 does not fit the search criteria being less than 3 letters. Yeah, the search function sucks because of this.

Search for heads in the 2.9L forum.

I would guess that the site does some indexing into some sort of offloaded search and ignores words less than 3 characters so it isn't bloating the index file.

What we've done in the past is ignore common 3 letter words like "are", "and", etc so that three letter terms could be searched.

Edit:
Indexing this way makes searches a heck of a lot quicker than using SQL "like" expressions directly against the database.

Pete

 

[donlightbody]

thanks for the info guys. I found a place online "cylinder heads international" in TX they sell rebuilt heads for the 2.9 $159 ea and I was told they have all castings, so I think in the long run, after the cost of the heads, magnafluxing, and any other work done on them (from salvage) it might not cost much more to just get these. Thanks guys. http://www.headsonly.com/index.htm

 

[MAKG]

They sell CRAP heads for $159 each. I had to charge back my 250 I-6 head because it was out of EVERY spec, and they refused a return.

What kind of POS operation does one-angle valve jobs these days? Three angles was factory spec even in 1972.

 

[donlightbody]

well damn! thanks for the warning