Hi all, I have a 1990 ranger single 4x2 with a 2.9l. I bought the truck brand new and Its never given me any problems until my trans went out last month. Then, the other day a heater hose came loose and it overheated before I could get it off the road. Anyway, I have a blown head gasket now with almost 400k. The truck is worth nothing except the $1000 I have in the trans. Aside from general maintenance and the usual expenses, this truck has cost me nothing except the 10k I paid in 1990. So, Im trying to decide whether to replace the head gasket, have the entire engine rebuilt or maybe even swap it out for a 4.0L.

I think the three choices will come down to how much money I want to spend on it. Can anyone tell me what my options are for a 4.0L? When I had the trans replaced I was in a hurry and the shop I had it at found a 5spd out of a 1997, cut the floor out a little and that's whats in there now. If I go with a 4.0, will I have any issues with that trans? Is there a specific year group of 4.0 that I would have to stick with?

Thanks for reading and your feedback.

 

The '97 5-speed was probably from a 4.0l vehicle, so would work fine with a 4.0l

To do the swap from 2.9l to 4.0l(OHV) you will need a complete 4.0l engine, the 4.0l computer with harness from a truck with a manual trans, also the MAF sensor.
Most buy a wrecked truck with a 4.0l as a donor vehicle.

The 2.9l and 4.0l shared the same basic block, which is why the trans bolted up so the swap doesn't require any major changes in the mounts.

The 2.9l has 140hp
The 4.0l has 160hp

Since you probably won't know the condition of a used 4.0l I would lean towards rebuilding the 2.9l and maybe update it a bit to get the extra 20hp.
Then it's just an in and out swap, no wiring issues.

Or just redo the heads and drive it till it drops, 400k on the chassis is alot, how much more will it go until the nickels and dimes add up to dollars, lol.

 

Thanks for the info, I for some reason thought the 4.0l was closer to 200hp. I think sacrificing 20hp for less headaches is the way to go. I was hoping it would make it another year or two, I was planning to rebuild it and fix it up with my son. It was my first truck and I thought it would be fun for his first truck but I don't know if its worth it. Im sure Ill have problems finding parts.

If I do rebuild it, any advice on selecting a shop, I just don't have the time or room to mess with it right now. I have taken it to a shop down the road, they service all but specialize in German brands. I don't even know if they would want to mess with it. I would take it to the dealer but, I would probably be better off buying a new truck for as much as they charge.

 

Yes, dealer wouldn't be my first choice for doing an engine rebuild.

Some terminology for engines
Short block = rebuilt lower end: crankshaft, rods, pistons and rings
Long block = short block with rebuilt heads installed
These do not have oil pans, valve covers or in some cases timing chain covers

Other costs are intake/exhaust gaskets, water pump, injectors, hoses, oil and coolant

Some auto repair shops do engine rebuilding in-house, others pull out the engines and send it, the long block, to a machine shop that rebuilds it, then the repair shop puts it all back together.
Machine shops rebuild motors every day all day, I like the idea of strength in repetition or practice makes perfect.
But it usually will take few weeks, or more, for this.

Since this is not a collector car there is also the option of buying a rebuilt engine(long block) and then have your current engine exchanged by a shop that will do that work.
Up side here is the time, usually just a few days to do the swap.
Down side is warranty since the engine seller and mechanic can point fingers back and forth if there is a problem, to avoid this it is often better to buy the rebuilt motor thru the mechanic, that way there is only one finger pointing, yours, lol.

A good source of who in your area would be good at this are the machine shops, they get engines from repair shops all the time and they know the shops that have issues because of having to rebuild the rebuild :)


A 2.9l rebuilt Long block looks to be about $1,300
Labor to remove and re-install would be anywhere from $700 to $1,200


With a collector car you want matching serial numbers for frame and engine, just FYI, so rebuild is the best way.

 

Thanks for the info, you have already saved me headaches. When you say the rebuilt long block is about $1300, is that what I can expect a machine shop to charge me or is there a good source? Also, if I went the exchange route do you know if a 2.9l is a 2.9l or will I have year compatibility issues? Thanks again.

 

The cost of the rebuild is area specific, hourly labor rate.
The $1,300 wouldn't include shipping, and engines are not light :)
And there is usually a "core charge" so you have to ship your old block/heads back
So local machine shop should be less.

Best thing is to call around, if you are in Houston there should be many to chose from.

In 1989 the 2.9l got the better heads, these are usually marked with casting number 89TM under the valve cover, also the better heads had a more square rocker mount, older heads had smaller and more of an oval shape rocker mount.
Earlier heads were prone to cracking when overheated.

But no compatibility issue in a 2.9l from 1986 to 1992


One other note, I think your 1990 is probably using a MAP sensor instead of a MAF sensor to determine fuel/air mix.
MAP sensor systems(speed density systems) can't compensate much for changes to the engine, so if you are tempted to put in a bigger CAM or increase compression to get a few more HP then you would be wasting your money, unless you also changed computers, wiring and switched to a MAF system.

 

I called around and about $1600 is the number. I found a machine shop which will tow, remove and replace the engine for $1600 so I think I will go that route. He offered me either an engine already rebuilt or they would do mine same price. How do I determine if I have a MAP or MAF? Are they located in/around the air filter box? If I do have a MAP sensor, is there any way of getting extra hp? Just curious, Ive always been happy with the power the truck had and really never thought it was underpowered, maybe geared a bit low. I can never keep the rear tires from spinning after a fresh rain, hahaha. I cant thank you enough for the info, you have really made these decisions easy and saved me a lot of trouble.

 

you were right in your earlier post there are two versions of the 4.0l the ohv4.0 was around 160HP however they do have an overhead cam version that puts out around 207HP so its up to you which way you want to go but swapping will require a computer and there are places you can buy a slightly used 4.0 with computer and harness for about the price your looking at plus labor of course. But like it was stated there isn't much to upgrade on the 2.9l i think the only person that even sells upgrade parts is Tom Morana but I've heard he can be hard to deal with and expensive so its entirely up to you at this point.

 

$1,600 sound reasonable for an in and out rebuild, not too much and not to little.

If time is not an issue then have them rebuild your engine.
Only reason is that if something happens 2 or 3 years down the road, after any warranty, you will always wonder "what if I used MY engine instead of an exchange", lol.

But I think an exchange is fine, if they warranty their work then they have checked the heads and block as best they can.


I think all the 2.9l Rangers had the Speed Density(MAP) system until engine was discontinued in '92
This link is a good site to bookmark and this page a good read about Ford fuel injection systems:
http://oldfuelinjection.com/?p=4

Engine power basically comes down to how much air you can get into a cylinder, more air means more fuel which = more power.
Larger displacement engine has more power because it sucks in more air.
Turbo or supercharged engines have more power because they can Force more air into the engine.

The MAF(mass air flow) system measures the air coming into the engine and adjusts fuel accordingly, up to a point, so using a cam that pulls in more air would improve power, the MAF sensor would see more air coming in and raise fuel level.

The MAP sensor is setup for the engine, it knows a specific vacuum level in the intake manifold at a specific RPM calls for X amount of fuel, increasing the air flow doesn't change the vacuum much so there would be limited performance increase without reprogramming the computer for more air flow.

Increasing compression would work with MAP or MAF, and it increases MPG..........BUT, always a big but when something sounds good, lol.
Increased compression is more efficient so you get more power from the same amount of fuel and air, the BUT is that gasoline self ignites when compression is too high, so you have to increase the octane level(octane is the temperature rating of gas, not energy) to prevent "pinging"(self ignition) or you have to retard the spark timing to the point of no power gain from higher compression.
So if a future of running Premium fuel is something you are willing to do for increased horse power then changing pistons might give you some extra power.
I wouldn't unless you were going full race, cam, pistons and your own fuel injection computer with larger injectors :)

 

Just talked to him, picking up the truck today, using my engine and turnaround 10 days or less. Anything I should take care of while the engine is out? I eventually want to paint the truck in its original shadow grey. The engine compartment is actually clean except for a few rust spots here and there. The engine is a lot cleaner too after a dosing of purple power, holly smokes that stuff works wonders. I cant believe how much grease and burnt, caked on oil it removed.

 

Back flushing the radiator and heater core is always a good idea.

These are basically big filters because of the design.

Coolant only flows one way thru them so any larger bits will get stuck, yes I know there should be no bits at all, lol, but lets come back to reality for the moment.

Back flush means you run water backwards thru the heater core, this can be done with a garden hose, then blow out the water inside the core and fill it with warm water CLR mix and let it sit 20 min, then back flush again.
Repeat as you see fit.

Rad needs to be pulled out to back flush, but same idea, try to push out any bits that might be clogging tubes.
Lie it flat and fill with warm water CLR mix, let it sit and back flush, repeat as you see fit.


The thing about doing a regular flush when you change coolant every two years, everyone does this right, lmao....ok back to reality again.
When you flush the cooling system in the vehicle the bits that do get cleaned off just end up stuck in the heater core or rad, lol, they usually don't drain out.

With all the wiring exposed with engine out not sure I would want to pressure wash bay you could do some local cleaning and spot painting for the rust.

 

Ok thanks