86 2.9l with 90 2.9l

[ubersoldatt]

hey guys , I just got burned on a ford ranger , bought it and heard nothing during the test run got it home and it has a rod knock, anyhoo, I decided screw it its the truck I want so im gonna dump an engine init, but after reading about the heads on earlier models cracking I want to but a rebuilt 90-92 longblock, or 88-90, but seems theres an issue with the front head bolts being different sizes, so im wondering what parts off an 86 engine are NOT gonna fit other years with the fat heads, any help would be appreciated, before I dump any cash on the block

 

[RonD]

Yes the earlier casting 2.9l heads did tend to crack the first time they were overheated.
Good read here on the 2.9l: http://www.therangerstation.com/tech_library/2_9_Page.shtml
Good pictures of the difference in the heads

'89 and up had the heavier casting heads

Never heard about any head bolt issue?

A rod knock will go away if spark is disabled on that cylinder, the "knock" noise is from firing, the loose connecting rod is slapping down on the crank journal.
But so will an exhaust leak and they sound very similar

Everything from an '86 2.9l will bolt on to a later model 2.9l, your '86 intake is better(larger) than later models so use that.

 

[huh?]

... front head bolts being different sizes...

is this in reference to some heads having 8mm holes and some having 10mm holes?

edit:

WhiteLX just started a topic about it here: http://www.therangerstation.com/forums/showthread.php?t=151443

 

[ubersoldatt]

is this in reference to some heads having 8mm holes and some having 10mm holes?

edit:

WhiteLX just started a topic about it here: http://www.therangerstation.com/forums/showthread.php?t=151443

yeah it is was getting reay to order a crate engine and it says to use the earlier engine , i just want to know if my intake and everything will bolt up with the newer heads, trying to stay away from 86 heads , they have one with 2.9l 90 -92 in stock but its says front head bolts are 10mm if 8 mm use 86t etc, dont wanna order the engine till i know my 86 parts will fit onit

 

[ubersoldatt]

Yes the earlier casting 2.9l heads did tend to crack the first time they were overheated.
Good read here on the 2.9l: http://www.therangerstation.com/tech_library/2_9_Page.shtml
Good pictures of the difference in the heads

'89 and up had the heavier casting heads

Never heard about any head bolt issue?

A rod knock will go away if spark is disabled on that cylinder, the "knock" noise is from firing, the loose connecting rod is slapping down on the crank journal.
But so will an exhaust leak and they sound very similar

Everything from an '86 2.9l will bolt on to a later model 2.9l, your '86 intake is better(larger) than later models so use that.

yeah i checked that it didnt go away or change volume , did each cylinder one at a time and no diffrence in sound or volume, it sounds like a lifter tick standing over the engine, but when you get under the oil pan it sounds like its comeing from inside the pan, thought it might be the oil pump, since the sound didnt differ at all with the spark check

 

[huh?]

food for thought

i've never done the swap you are looking into but the following information comes from reading through this forum and looking at machine shop websites that offer 2.9l heads for sale:

the 8mm vs. 10mm bolt holes are on the end of the heads and are utilized for attaching the brackets for a/c, p/s pump, alternator, etc.

i've read posts that advised others who did what you want to do to use their older(86 or 87) throttle body since it has a larger diameter than later year 2.9l throttle bodies. i can't say for a fact that the earlier intake will bolt to the later heads, but that is simply because i never tried it myself and i don't remember reading anything here that states that it does. (i would assume it does,though.)

i think i've read a couple of posts here that said the valve covers are different so you may need to score a set of those.

ecm may or may not be an issue.


although i can't offer advice as to buy or not, the above stuff you can maybe use for site or web searches or discussion with parts guys or mechanics. perhaps one of those who know will post a "go" or "no go" in regards to a hefty purchase.

by the way, have you done a compression test or slap a vacuum gauge on the manifold? just curious.

 

[ubersoldatt]

thanks , i can hog out the brackets if needed and sure i can find some valve covers for the later model heads at pull apart if i do this should be ok with the ecm, since im keeping the same intake and electronics and such

 

[Slammin Sam]

Ford dropped the egr valve in 88. That may confuse the computer, but I'm sure there are threads on here dealing with that.

 

[ubersoldatt]

Ford dropped the egr valve in 88. That may confuse the computer, but I'm sure there are threads on here dealing with that.

maybe guess were gonna find out, i ordered it

 

[96Indyram]

any update?
You will have no problems with the bolt size difference..I just did this swap.

But you might have to buy 10mm bolts to bolt on all the brackets if you dont have them.
so far....I have not had any check engine lights or computer codes come up by going to a non-egr engine.
also your engine you ordered may not have the knock sensor... my old one did..my new one dont.