New Bronco Upgrades

I recently purchased a 1989 Bronco II with only 83000 miles on it and the only rust is body rust. There was a lot of it but the body rust was almost entirely taken care of by the previous owner so now it only needs a fresh coat of paint rather than bodywork. The only issue I have with it is in the motor. I already know that the 2.9L were nothing but trouble but I want to know where to start putting money into this. It sounds like an old ford engine, it just ticks when it runs. I assume it is the lifters ticking as that is what most sources agree caused the ticking. It also drops in oil pressure when I come to a stop after I've driven it at highway speed or at least over 50mph anywhere from after 15-45 minutes.

What I want some opinions on is what is wrong exactly and what I can do to fix it. I would like to keep the same motor rather than go for a 4.0 swap for 2 reasons. 1 I don't want to destroy the A4LD transmission on my daily driver with a bigger engine. 2 I'm still in college and live at home and my parents would not appreciate a donor truck showing up in our already packed driveway

Any opinions and help would be appreciated

The 2.9L isn't a big powerhouse, but I don't think it is nothing but trouble. And yes they do tend to tick. I had one tick for most of its 192K mile life and then it was an issue of body falling apart not making it worth fixing.

I have no idea why it may drop low after all that driving other than it perhaps getting hot, but if thermostat is doing it's job, it shouldn't require highway speeds.

Then again I am a hack at this so my not having specific ideas doesn't mean others won't have some ideas.

The 2.9 is a good motor. They can kill them selves if overheated but the big secret is to not allow it to overheat! Mine has almost 200k on it and it runs great (for the 80k that I've owned it). Of all things on the truck, I have the most confidence is my 2.9. It's a noisey, Harsh, low powered little motor though.

But the Oil Pressure drop is a problem, 2.9 or not. Are you using an aftermarket Mechanical Oil Pressure gauge or are you going by the stock gauge. Chances are, the stock gauge is correct BUT it's electrical and the stock gauges are known for not being 100% accurate.

When the pressure drops are you hearing any excessive rattling or ticking? Is the oil level correct? if so, I would try changing the oil to see what happens. Hopefully, the pickup screen isn't clogged and a oil passageway isn't partially blocked.

Grab an explorer and put the 4.0 in it. Problem solved. Enjoy B2 afterwards.

When I said the 2.9 is trouble I didn't mean it as in if you have one you have a problem, I just meant they seem to have more problems than solutions, so if you let it develop a problem you are in bad shape. In retrospect that really would be true of any motor.

To try to explain the oil situation a little more I have enough oil according to the dipstick, changed the oil less than a month ago and also replaced the gauge sender because the original did not function at all but it should still be stock. When I start the truck my oil pressure is fine. If I drive at high speeds (anywhere from 50-75 mph) for 15 minutes or more the pressure is still good but the ticking increases in volume (not to an obnoxious level but enough that if you roll the windows down it is noticeable to people not listening for it). Then when I slow down to a stop my oil pressure gauge drops. Anything above the idling rpm and it reads that I have good pressure but at idling rpm it reads as low. Then when I put it in park it reads good again so...

As for the 2.9L being low powered I would disagree coming from a 3.0L Ranger

My point is that you can throw money at fixing a 2.9 all day long, and in the end it would still be cheaper to swap in a 4.0. It is a bolt in, takes the same motor mounts, same tranny. The harness even plugs into your dash. You have to splice the lights into the harness and thats it.

The rewards are awesome. The 4.0 is not underpowered and gets decent mileage

NoahS said:

When I said the 2.9 is trouble I didn't mean it as in if you have one you have a problem, I just meant they seem to have more problems than solutions, so if you let it develop a problem you are in bad shape. In retrospect that really would be true of any motor.

To try to explain the oil situation a little more I have enough oil according to the dipstick, changed the oil less than a month ago and also replaced the gauge sender because the original did not function at all but it should still be stock. When I start the truck my oil pressure is fine. If I drive at high speeds (anywhere from 50-75 mph) for 15 minutes or more the pressure is still good but the ticking increases in volume (not to an obnoxious level but enough that if you roll the windows down it is noticeable to people not listening for it). Then when I slow down to a stop my oil pressure gauge drops. Anything above the idling rpm and it reads that I have good pressure but at idling rpm it reads as low. Then when I put it in park it reads good again so...

As for the 2.9L being low powered I would disagree coming from a 3.0L Ranger

Click to expand...

I can vouch for that..My brother in law has a 3.0 and it's a slug!

Well, To me, this sounds like it could possibly be a sludge build up problem. Perhaps the heads oil return holes are partially plugged? I'd pop the valve covers off (get new gaskets of course) and check out the build up and see how it looks. This is the 1st thing I'd do if i had the issues you do right now.

Another thing worth mentioning is the oil pump. I'd say it's OK since it's not always low pressure. Same goes for the oil pump screen and worn cam bearings. I would think these would be bad if it ALWAYS had low oil pressure.

Hopefully someone else chimes in on this for some more ideas...

The lifters rattling on the highway is interesting. What weight oil did you put in? Perhaps the oil is shearing and not properly lubrication the lifters (also indicates sludge!)

As far as the idle pressure, it's fine until you are on the highway and slow down THEN it drops? Just making sure I understand. I think the reason why it gets better in park is because the RPM's are up a bit more when it's not in gear.

And if all else fails and you do for some reason decide to swap motors, the 4.0 is not a bad idea AT ALL! Especially because you have an 89.

Even A4LD might survive (But I understand that you want to keep the 2.9 for this alone). There's a few brave souls here who've kept the 2.9 A4LD going.

I have a 302 where the oil pressure gauge drops to 0 after a highway run... took it in and had the pressure checked at the shop, changed the sending unit also, mechanic says the pressure is fine not to worry about it, so I dont.

Does the 2.9 have mechanical or hydrolic lifters? Mechanical are very easy to adjust and hydrolic are very easy to replace, a little ticking isnt really a good reason to swap a motor.

4.0L swap wouldnt be my choice, in fact Ive sold two of them since owning my B2, nothing against the 4L but its alot of work for very little gain, but then I have a 2.8L w/duraspark so thats nothing like the 2.9L setup.

Doesnt sound like your in a position to do a major swap anyway so I suggest just getting the pressure checked at a shop and fixing the ticking yourself, drive it as long as it keeps running... that gives you time to think and plan for other possibilities.

Good points. The 2.9's are hydraulic.

Spede Demn said:

I have a 302 where the oil pressure gauge drops to 0 after a highway run... took it in and had the pressure checked at the shop, changed the sending unit also, mechanic says the pressure is fine not to worry about it, so I dont.

Does the 2.9 have mechanical or hydrolic lifters? Mechanical are very easy to adjust and hydrolic are very easy to replace, a little ticking isnt really a good reason to swap a motor.

4.0L swap wouldnt be my choice, in fact Ive sold two of them since owning my B2, nothing against the 4L but its alot of work for very little gain, but then I have a 2.8L w/duraspark so thats nothing like the 2.9L setup.

Doesnt sound like your in a position to do a major swap anyway so I suggest just getting the pressure checked at a shop and fixing the ticking yourself, drive it as long as it keeps running... that gives you time to think and plan for other possibilities.

Click to expand...

I've done lifters and I have done the 4.0 swap. I'll choose the 4.0 anyday.
My 4.0 outperforms my 2.9's handsdown.

Of course a 4l will out perform a 2.9l... but the op told us he doesnt want to go that route.

My oil pressure only reads low when my engine is running hot at idle, thats about as clear as I can think to make it. When the engine is cold it says idle pressure is good once it is hot it says it is bad, everything other than idle it reads good. I'm using 5W-30 oil, If I am thinking about this correctly switching to a higher oil (5W-40 or 10W-40) would make the oil thicker so it should give me more pressure at high temperatures. Would that be worth trying out? I want to make sure I'm not thinking about that backwards or anything.

I know I can try replacing the lifters to quiet the ticking, as a matter of fact I planned on doing that this summer once school let off. Is there anything else I should look at/plan to replace while I am doing that?

The sludge build up is a good point and I'll definitely try to take a look at that if something like the oil weight change doesn't fix it, if it does that would probably get lumped with the lifters as a summer project

Just to recap on the 4.0 I unfortunately don't have the room to just pick up an explorer and I would absolutely consider it before doing a complete engine rebuild on the 2.9 but what I am looking for now are solutions to what I'm hoping are minor issues. I don't need the additional power, this is a daily driver, not a racetruck or mudbogger, it is used to get from point a to point b and occasionally have some fun in the middle.

If you have lifter tick in a 2.9 you need more than just lifters, you need cam bearings too. Cam bearings means the engine comes out.

Don't buy a whole donor vehicle for a 4.0 swap. Just go to the pick'n'pull and get an engine a harness and a computer.

A4LD is A4LD is garbage, so that's not too much of a concern. The 2.9 unit should hold up to the 4.0 as well as a 4.0 one would. The reason you see a rash of failures of 2.9 A4LDs behind 4.0s is the 2.9 didn't have the guts to finish breaking the trans.

Oil pressure on my F150 does the same thing as your B2, its normal except at idle 'after' driving it on the highway, if I dont go on the highway it it doesnt drop below normal... and its done that for two years now, even pulling the camper trailer. Have a shop test the pressure and see what they recommend, I wouldn't try heavier oil, if the pump is getting weak the heavy oil is harder to pump and will just kill it sooner.

You can change the lifters yourself easily, on a budget, over a weekend, all you need is gaskets, maybe some extra hoses in case any break, can even paint the valve covers and intake while they're off so it goes back together nice and clean.