4.0L Head Replacement or Engine Swap

[93RedRanger]

Hey guys. I have a '93 4.0L 4x4 Ranger with about 200,000 miles on it. I'm looking for a little advice on keeping this piece on the road for another year or two. I recently did a bunch of work to the truck (about $1,300 in all) just to discover that I have a blown head gasket. So far I've replaced all the ball joints, put in a new fuel pump, replace the entire cooling system (engine overheated when the water pump ate it), and a whole slew of other stuff. My question is, should I pay to have a head job done or should I put in a used engine and reinstall my new water pump and stuff on that motor? I found a few used engines with 70k to 80k miles on them between $500 and $700. I thought it might be a fun project to swap the motors out and I'd learn a little something in the process, but I'm finishing my last semester in engineering school this summer (whoo hoo, only took ten years!) so I probably won't have time for much else. So... I'd probably be better off paying someone to do the swap for me.

The engine I have now also has a leaking rear main and usually doesn't start for several tries in the morning. Don't know if the starting issue is related to the head gasket problem or not, just trying to give all the info I can. I'm just curious if any of you guys with some experience in this area could weigh in on the issue. I'm trying to get it in good running order so I don't have a car payment while I'm repaying student loans for the next couple years. Plus, it's been a good little truck and I hate to let it go when I've already spent so much money on it. Any thoughts? Anybody done this particular engine swap? I do a lot of my own work, but I'm not sure how involved that would be and how long it would take.

 

[Nhaz]

How is the rest of the truck? If its in great shape and will last many more years and the engine is overall dying slowly on you, Then sure I'd swap the engine.

Unless you saw the engine running in something else I am always a tad leery of swapping engines. you are trading the gremlins you know for gremlins you don't.


But, if the rest of the truck isn't so hot or is in the category of fix something every couple months or along those lines then the head gasket isn't a huge thing to change.


Rear main seals are pretty easy to change as well.

 

[93RedRanger]

For a 93 model it's not bad at all. It's got the usual dings and bangs here and there, but overall not a bad truck. The only other problems that need addressing are some brake work in the rear and I'm getting a popping noise from the drive train during starts and stops. Other than that, nothing I can't live with. Heck, I've already fixed most of my other problems. Surely there can't be much else left.

When I called about the used engine the other day, one place told me that they could set me up with something between 70 and 80 thousand miles that had been dyno tested and comes with a 30 day warranty. Is that the norm when buying a used engine? Does a dyno card really tell you that much about a used motor?

 

[Ranger44]

I would really just go with an engine swap. As far as engine swaps go, 4L to 4L isn't bad at all.

Opening an engine usually lets all the "bad stuff" in and many problems start to pop up when you put it back together.

When looking for an engine look for one out of a vehicle that has body damage or a DEAD A4LD behing it. If a truck doesn't have either it's usually due to engine trouble. HEAR and SEE it run. A dyno card doesn't really prove anything, but a warranty will help.

 

[stx4.0]

Defineatley go with the engine swap!The same thing happened to one of my rangers.The water pump went out and the engine overheated.Anytime you overheat an engine there are all kinds of bad things that happen(not just damaging the heads) depending on when its caught and how long it overheats including burning the rings up which replacing the heads will not fix.On mine I tore it apart and bought new alabama heads,had the radiator cleaned,checked the coolant passeges in the block,new and cooler thermostat(factory one I think is 215),way too hot in my opinion.I checked the block also for warpage and when it all went back togeather it still overheats which I think I have narrowed down to a warped block even though I went over it with a fine tooth comb.Let me tell you,its not fun to do all that work,spend all that money and be as thorough as I was only to end up not fixing the problem.

 

[AllanD]

It's a "replacement", not a "swap"

Normally I'd ask where is the gasket leaking but if it has to crank
a bit to start on a cold start that's a symptom of old age.

AD

 

[stx4.0]

Replacement/swap/change.It all depends on where your from.As long as you speak english,it shouldn't be too hard to figure out the meaning of any of them.I think we all agree your probably better off getting another motor.If you had endless time,money and patience,then it might be worthwhile to tear it apart and fix it.

 

[93RedRanger]

Sounds like everyone is confirming what I was thinking. Seems like everytime I fix something, I find something else that needs fixing. I'd love to just drive the dang thing.

Swap, replacement, whatever... you know what I'm saying here.

Anyway, thanks for weighing in. I guess my search for a good used engine will continue next week. Seems like a lot of the salvage places I've called already have the engine out of the truck, so I don't know about finding one that I can see run, but maybe I'll luck up on something.

Any tips for a first timer when changing engines? (Anything outside of the obvious I mean) I'm definitely going to go with a different engine. I never considered that I might have warped the block itself. I also thought that the stock thermostat runs way to hot.

Anyone know of a reputable place to get a good used engine in North Alabama? (Preferably somewhere between Huntsville and Chattanooga, TN)

 

[Donnie strickland]

Just by way of information, no Ranger has ever come with a 215ºF thermostat. The factory t-stat begins to open at 192º. From Ford:


Thermostat Test


The thermostat should be replaced only after the following tests have been performed:
Heat Test 89°C (192°F) Thermostat Immerse the removed thermostat in a 89°C (192°F) solution of antifreeze and water mixture. An 89°C (192°F) thermostat should open to 0.08 mm (0.0003 inch) . When immersed in a 100°C (212°F) solution, the thermostat should open to 3.2 mm (1/8 inch) .


Visual Test
If heat is not available, the thermostat should be checked for leakage. This is done by holding the thermostat up to a lighted background. Leakage of light around the thermostat valve (thermostat at room temperature) indicates that the thermostat should be replaced with an original equipment, approved thermostat. Some thermostats have a small leakage notch at one location on the perimeter of the thermostat valve which is considered normal.

And notice what they say about a cooler-than-specified engine temperature:
Engine performance concerns such as hesitation or stall, rough idle, and/or poor fuel economy may be caused by the thermostat stuck in an open position or opening at a temperature lower than specified.


Your truck will never run hot because of the thermostat, unless it's defective.

 

[93RedRanger]

It may not run hot, but it will sure make you think it's going to when the needle gets all the way over to the H before it comes back down. Mine doesn't run hot since I swapped out all the cooling system components and put in a new thermostat, but it does run hotter than you would expect. My buddy got in the truck a while back and was like "you're trucks about to overheat!"

 

[93RedRanger]

Used engine coming in tomorrow. I'm pretty stoked to get on it and put it in, but I can't do that until my Thermal System Design programming is done for school. Dang school...

Anyway, any suggestions for doing any tune up items on the replacement engine while it's out of the truck and easy to get to? I've got new plugs and wires ready to go on and I'm going to swap the new water pump from my old engine to the donor along with a cooler thermostat. I might go ahead and throw some paint on it if it looks rough. Anything else that you might normally do while the engine is nice and accessible?

 

[whynotthinkwhynot]

Read the 4.0 Tech page and get the rear seal fix put in your new engine before installing it. When I've swapped or replaced or installed engines before, I always go through the jobs on the salvage block that are difficult to do when in the vehicle. Front and rear seal, and maybe the oil pan. On a 4.0, I'd definitely consider pulling the oil pan and replacing the oil pump pickup, or cutting the metal cover away from the screen. Once you see it, you'll understand. The Melling replacement part is the same diameter, but all screen like older V8's. That's about all I can think of, right now it's time to change a diaper.

 

[bigredscowboy]

Anything else that you might normally do while the engine is nice and accessible?

check the Timing chain while you've got the water pump off

 

[93RedRanger]

On a 4.0, I'd definitely consider pulling the oil pan and replacing the oil pump pickup, or cutting the metal cover away from the screen. Once you see it, you'll understand. The Melling replacement part is the same diameter, but all screen like older V8's. That's about all I can think of, right now it's time to change a diaper.

I hate changing diapers... I had to stay home from work for a week to watch my 3 year old and 1 1/2 year old while my wife recovered from surgery. Yuck. One potty training and the other going through diapers like candy.

Anyway, that's the first I've heard of an oil pickup problem with these. I had thought about replacing the oil pan gasket anyway, so I'll definitely take a look at it. Not sure what "Melling" is. Is that a brand or the name of a specific part? You wouldn't have a part # would you?

Oh and thanks for pointing me to the rear main seal fix. My current engine's rear main has been spitting oil for a while and I'd like to not have that happening again any time soon.

 

[93RedRanger]

check the Timing chain while you've got the water pump off

Anything specific to look for other than obvious wear? Is there some spec for how tight it has to be? Something like how much is deflects with a given amount of pull (kinda like a motorcycle drive chain)? I've done a lot of basic repair work, but I've never fooled with a timing chain or adjusted timing or anything like that.

By the way, I appreciate all the help from you guys. If at any time I'm asking something stupid that I can find in my Haynes manual, feel free to let me know.