I have a 1990 Bronco 2 with a 2.9L at 186,000 miles. It runs smooth, has always been a slug in low rpm but also has been decent in hp mid range around 4000-5500 rpm. I noticed a lifter noise today while it was idleing and I was standing next to the right fender. It sounds a little choppy at the tail pipe and yesterday the t-case shifter would shake occassionally along with the motor. I think It needs now valve springs and 3-5 angle valve job. It is very thirsty! I used to get 5 mpg but now I get 9 city and 13 highway! I am not going to put any more signifisant mondy into this vehicle as it has guzzelled too much already but I intend to drive it until the engine falls out!

I may not fix it but I wonder what you guys think may be the problem. I think that this is a very forgiving motor as it has seen the other side of 5000 rpm a lot! I do think that cruising 75 mph up big grades, down hill, normal cruising, wild offroading through soft sand, mudd bogs, rock crawling, hydroplaning through ponds, ect! Oh and we even hauled a empty horse trailer up a hill for a block too. I think that qualifies as beating the living hell out of it!

 

Check your oil pressure with a real gauge. By the time the idiot light (or in your case idiot gauge since it always reads in the same place) shows up, the damage is already done.

I had a 1986 bronco2 with the 2.9L V6. It started ticking about 80,000 miles, and continued to 164,000 miles. At that point, multiple lifters were ticking and the thing sounded like it was full of rocks. Upon pulling the motor and inspecting, the thrust bearing surface on the crank was ate out by the bearing itself (odd) and the counterweights were hitting the block! Not to mention, multiple collapsed lifters. And to think, I used Mobil 1.

So, it could be a simple valve lifter problem, or a symptom of something much worse...

If you really wanted to fix it, after checking the oil pressure, pull the valve covers and rocker shaft assemblies. Then, push down on the pushrods to see which lifter is collapsed. Replace the offending lifters and be on your way. If the oil pressure is low, then pull the pan and slide some new bearings in it. Also while the pan is off, make sure the oil pump and pickup bolts are nice and tight.

OBTW, mine always got about 20mpg. Too bad it died, since the Explorer that replaced it rarely gets above 15.

 

You make it sound so easy! Just a note, you cannot get the oil pan off with the engine in place, you can jack it up, but it's probably going to be easier to just pull the motor. Heads also have to be removed to get the lifters out. (New head gaskets, head bolts, etc..)

Pete

 

I will just let the engine blow up and wheels fall off! I change the oil about every 3000 miles and I put ford motorcraft synthetic 10w 30 last week. I will save my money as I am building a big Ford V8 in my scout and am slightly interested in how long this Bronco will last! I expect this motor will self distruct sooner or later and am not concerned about smoggers!

So I am looking at barings wearing down, lifters drying up,ect.

thanks for your input!

 

I can do that. There is in fact a crossmember blocking the oil pan and I have a engine crane so that would be relatively easy to pull it out.

 

Ok, the oil pan I'll believe, but in no world do the heads have to come off to get lifters out. Intake, yes. Heads, no.

 

On the 351 in my F-150 and the junked 302 in the scoult the I had to take out the rockers, the pushrods came out, then the lifters. I assume that is how it is for almost all V pushord engines.

 

I'd be very interested to know how you were able to get the lifters on a 2.9 out with the heads still in place. As you can see from the pic, a portion of the head obstructs each lifter bore which prevents the lifter from coming up far enough to clear the bore:



I put all new lifters in mine when I did the heads, it still had the typical 2.9 lifter tick which would come and go.

 

OUt of courosity will the the 2.8L carburated intake fit in a 4.0L? I am not planning such but just curios as that would make a nice setup for a 4x4 lighter than mine!

 

No, the valve arrangement is different. Even though the 4.0 derives from the 2.9, which in turn derives from the 2.8, there aren't many parts that will interchange. They just changed it around too much with each redesign.

This means that there's no carburated intake that will fit the 4.0, so you'd have to fabricate your own. There's also the ignition problems to work out, since the 4.0 has no distributor and it's ignition is controlled by the computer.

 

My bad!

It has been about 6 years since I had mine apart. Thanks for the correction.

 

No prob...you seemed so certain, you had me doubting what I was sure was correct...!

 

Rocker arm shafts get plugged up restricting oil flow.

 

Hi
you take the 2.6 offenhauser 4bbl intake will bolt right on the 2.9 head and block i dont know about the 4.0 liter head but on the 2.9 that intake will fit right there in place for distributor you replace the distributor gear to the 2.9 one and drop it in place