98 Ranger Intake or Head Gasket Replace

[kb406]

Hi All,

As of last night, my 98 Ranger 3.0L 4x4 started blowing thick white smoke out of the tail pipe, a clear sign of a coolant leak somewhere in or around the cylinder. The obvious diagnosis would be a blown headgasket. But I don't have any coolant in my oil, or vice versa. Nor are there any visible coolant leaks or on the ground below.

I tried to take it to the mechanic this morning for a cylinder compression test, as well as a coolant leakdown test. Due to a combination of sickness and vacation, they are understaffed and not able to look at it until next week. This is my daily driver, though, so I can't afford to wait that long. Hoping to tackle the project this weekend if possible.

So, a few questions:

1) If I can get my hands on the right tools, will a simple $35 compression tester do the trick? Similarly, will a simple block tester rental tool from autozone or o'reilly be able to accurately diagnose a cooling system leak? In other words, can I trust myself to diagnose or is this better left to a garage?

2) If it is a head gasket, why is there no cross-contamination between coolant and oil? Is it possible that this could be a much simpler intake gasket?

3) If it is just an intake gasket, can I leave the head alone? Or would it be best to replace the whole works right away.​

Thanks, in advance, for all your help. I'll check in regularly until this is solved.

 

[kb406]

One last question:

How dumb is it to drive this truck to and from work (10 miles round trip, up a decently steep hill) until the weekend? I really have no option, but I also don't want further damage.

 

[Spott]

1. Yes, a basic compression tester will do the job, and it's not hard to do it yourself (although it's a little easier if you have a helper). I dunno anything about a "block tester" tool.

2. There are separate coolant, oil, and air/exhaust passages in the block and head. Where the crack is located and how large it is will determine which systems leak into which others. While it could theoretically be a head crack, block crack, head gasket leak, or intake gasket leak, it's tough to know exactly which it is without some disassembly.

3. Sorry, I don't know the specifics of the 3.0.

 

[kb406]

Thanks, Spott. Appreciate the help. I'm no longer at work, so I can provide a bit more details, in case it helps diagnose the problem and/or recommend next steps.


Attempts to Solve
This truck is brand new to me as of three weeks ago. Gave it a good, solid inspection before purchase and did not detect any issues. First weekend of ownership, I put the raft on the back and tow it over a pass. Two cylinders misfire, an O2 sensor fouls, and I notice some sort of stop leak in the coolant, which was not visible during inspection (or I just missed it). So I replace all plugs and wires, flush and replace coolant, and put in a new O2 sensor. That fixes the misfire, but the hard idle appears. A couple days later, the white smoke appears.

Symptoms (some may be unrelated)
Engine hesitates and stumbles and in gear on low rpm
Just started blowing white smoke out of tailpipe
Coolant bubbles (boils?) into overflow tank; I notice it after shutoff, but likely happening while driving
Engine oil is clean, not at all milky
Coolant is clean and green, no visible oil
No visible coolant leaks around engine or on ground beneath truck
Heater core is partially plugged (I believe) - blows lukewarm air - hose in is hot, out is cold

Possible Diagnosis
Internet research leads me to believe it is most likely a blown head gasket. I'm hopeful that it might just be the intake gasket, which is still a sizable undertaking. Are there other possibilities to consider before tearing into the engine?

I've read that a blown head gasket is extremely uncommon in the 3.0L. Is this true? If so, should I also be looking for another problem that caused the gasket failure? Something like a bad timing chain cover gasket, water pump, etc?

Since the truck is new to me, I'm at a bit of a loss. Not sure how much money to drop into something that may have a lot of problems. I fear this might be a patched head gasket that finally blew through. If that's correct, could I be looking at far more than a simple head gasket repair/head replacement?

 

[black_demon69]

Thanks, Spott. Appreciate the help. I'm no longer at work, so I can provide a bit more details, in case it helps diagnose the problem and/or recommend next steps.


Attempts to Solve
This truck is brand new to me as of three weeks ago. Gave it a good, solid inspection before purchase and did not detect any issues. First weekend of ownership, I put the raft on the back and tow it over a pass. Two cylinders misfire, an O2 sensor fouls, and I notice some sort of stop leak in the coolant, which was not visible during inspection (or I just missed it). So I replace all plugs and wires, flush and replace coolant, and put in a new O2 sensor. That fixes the misfire, but the hard idle appears. A couple days later, the white smoke appears.

Symptoms (some may be unrelated)
Engine hesitates and stumbles and in gear on low rpm
Just started blowing white smoke out of tailpipe
Coolant bubbles (boils?) into overflow tank; I notice it after shutoff, but likely happening while driving
Engine oil is clean, not at all milky
Coolant is clean and green, no visible oil
No visible coolant leaks around engine or on ground beneath truck
Heater core is partially plugged (I believe) - blows lukewarm air - hose in is hot, out is cold

Possible Diagnosis
Internet research leads me to believe it is most likely a blown head gasket. I'm hopeful that it might just be the intake gasket, which is still a sizable undertaking. Are there other possibilities to consider before tearing into the engine?

I've read that a blown head gasket is extremely uncommon in the 3.0L. Is this true? If so, should I also be looking for another problem that caused the gasket failure? Something like a bad timing chain cover gasket, water pump, etc?

Since the truck is new to me, I'm at a bit of a loss. Not sure how much money to drop into something that may have a lot of problems. I fear this might be a patched head gasket that finally blew through. If that's correct, could I be looking at far more than a simple head gasket repair/head replacement?

3.0l like to crack heads in the exhaust valve port. so i would count on getting a set of heads (of course you still need to get your heads checked to verify) if above is true then you would see white smoke but no coolant in the oil... do the glove test or i believe there is a dye that will tell you if you have exhaust gasses in coolant although ive never used it.

 

[Big Jim M]

Ok so you didn't have bubbles in the coolant until you changed the coolant an refilled it.
The most common problem here is not knowing how to complete fill the coolant system.
Did you turn the heater to hot to completely fill the system?
Did you start and run the engine till hot while filling?
Did you make sure the radiator cap was the highest part of the coolant system while filling?
If it didn't boil over before than it is almost a positive you didn't get it full.

If you actually have coolant in the cylinders you should have compression in the coolant system. It is a given! If the intake manifold is leaking it should only leak into the engine oil. Seeing smoke at start up might be from a gasket leak while stopped. If so then when started compression will force coolant out almost immediately.
Big Jim

 

[kb406]

Thanks, Demon. You lend additional weight to one of my fears. Good to know, going in, that I will likely need new heads.

Ok so you didn't have bubbles in the coolant until you changed the coolant an refilled it.
The most common problem here is not knowing how to complete fill the coolant system.
Did you turn the heater to hot to completely fill the system?
Did you start and run the engine till hot while filling?
Did you make sure the radiator cap was the highest part of the coolant system while filling?
If it didn't boil over before than it is almost a positive you didn't get it full.

I did turn the heater on while filling but, as mentioned earlier, the heater core is plugged so I'm not sure much coolant made it through.

I did run the engine until hot, let the fan kick in, watch the coolant drop into the engine and then topped off.

Not sure what you mean by "make sure the radiator cap is the highest part of the system while filling." Isn't it always the highest point?

I believe I filled the cooling system fully. For the sake of example, let's say I hadn't done it correctly. There's no way that it could lead to coolant in the cylinders, is there?

 

[Big Jim M]

If you have SEEN coolant in the cylinders then you have to at least take the head/heads off to see what is happening in there.
A good check is to pull the sparks and see if any of them are rusty.
From here it looks like you purchased a broken engine. The seller obviously KNEW what he was selling.
Depending on the location of any crack it is possible to weld them up if the crack isn't directly on a gasket surface. I welded a 76 closed chamber head back in 80 and I know for sure it worked for 8 years. I imagine it is still in service somewhere.
But first thing to do is to find out what is happening.
Also NO some engine systems do NOT have the radiator cap as the highest point in the system. And when filling on a downhill slope the cap can still be lower than other parts of the cooling system.
If you do pull the heads then by all means take the heater core out and replace and for gods sake flush many time to get all that crap the seller put in there OUT!
Big Jim

 

[kb406]

Thanks, Jim. Seller claims he had no clue there were any issues. I find that very hard to believe, but unfortunately I'm not sure I have any recourse.

You make a good point. I haven't seen any coolant inside the cylinders themselves. But white smoke and water pouring out of the tailpipe can only mean one thing, right? There's coolant pushing through the cylinders?

 

[enjr44]

Sorry to hear that someone sold you their problem. Been there and done that. That being said, you are where you are, so.....

You are in the ball park, there is a leak in the top of the engine that is pushing and pulling coolant. Pulling coolant into a cylinder on the intake stroke (intake or head) and pushing air/combustion gases into the cooling system on the compression stroke (bubbles in the radiator). Oil and coolant mixing does not always happen and that is good news. But, to be realistic, if it is a cracked head it is not going to be a weekend job, unless you have all the parts on-hand.

First do a glove test. Pull the plug wires!!! You don’t want the engine to start. And it works best if the radiator is not completely filled to the top and the engine is cold. That is a test where you plug the radiator’s overflow outlet, and put a rubber glove (or balloon, or whatever, some have used a condom) in place of the radiator cap and secure it with a rubber band or whatever. Crank the engine, if the glove jumps around a piston is pushing air into the cooling system. If it just lays there you probably don’t have a head gasket problem. But, coolant in the exhaust does mean you have a cross leak. If it is jumping around, you can pull the plugs, one at a time to find which cylinder is the problem.

Next do a compression test. Pull all the plugs. Prop the throttle open so the engine gets all the air available and do the test. Test each cylinder for about 5 seconds and write down the results. Do each cylinder the same way so you can compare results (all the cylinders the same way). IF all is good all cylinders should be within say 10 percent of each other. If they are all about the same I would suspect an intake leak. If one or two (next to each other) is way lower, I would suspect a bad head or head gasket.

Good luck and remember that if you mess with old vehicles enough you are going to get hosed by some SOB. And no, I would not drive it. There is a good chance you will be looking at a new engine.

Ed

 

[adsm08]

Do a block test. Your issue is probably head gaskets, as they can let coolant into the combustion chamber and burn it off without it making its way into the oil. Intake gaskets almost always get it in the oil.

A block test is really simple, and extremely accurate, if somewhat imprecise. The block tester is simple, you add a blue fluid to a tube and pump air from the cooling system through it. The dye in the fluid reacts to a chemical that is pretty much only found in exhaust gas, and turns yellow. This will let you know for sure if exhaust gas is getting into the cooling system. In this sense it is accurate. It is imprecise in that it won't tell you if you have a blown gasket, warped/cracked head, or a cracked block.


The only thing to be careful with is to make sure you do the test in a well ventilated area. One time I had all the shop doors closed and no exhaust hose on my tail pipe, I reacted the whole bottle when I opened it because I'd had the engine running.

 

[kb406]

Thanks enjr44 and adsm08. Both recommendation will come in handy when I diagnose tonight. I delayed moving it all week. Currently downtown, but need to drive it 10 miles up a steep hill tonight to get it to my garage. Little nervous, but really don't want to pay to have it towed.

Once I diagnose, I plan to spend the weekend disassembling the top of the engine. In preparation, I have a bit of research to do. Thought I'd ask the TRS brain trust as well:

1) Assuming it is a head gasket (it is, I just need to accept it), can someone point me in the direction of a good step-by-step procedure for a head gasket replace? Ideally on a 98 Ford Ranger 3.0, or as close to that as possible? Youtube videos, blog posts, old threads, etc. Better yet, anyone know where I can get a free (or cheap) pdf shop manual?

2) If I'm tearing the engine down this far, I might as well do some other preventative work. I've read that the 3.0L has a pretty common timing chain cover gasket leak. Might as well replace that. If so, should I put in a new timing chain (nearing 120k miles)? Water pump is pretty old, possibly even the cause of the bhg. That will probably go as well. Anything else you'd recommend?

3) Parts recommendations:

Is there a specific gasket set that is better than the rest? Do the gasket sets typically include everything needed (exhaust manifold, intake manifold, etc, etc)? I'll get new head bolts as well.

How about used or reman heads, if it comes to that? Where can something like that be found? I've got a local guy that might be able to help, but looking for other options in case that fails. Hopefully my heads can just be machined, though.

Any other parts I'm missing?


I'll post a parts list and list of good resources before I start, as well as photos of the process.

 

[Big Jim M]

I never machine heads/valves! If I have a bad valve I replace it and lap in in place in my garage. Machining is simply put MORE WEAR on the head and valves. The thinner the valve is the more susceptible it is to burning a hole in itself. The deeper the valve is set in the head, the less available space there is for mixture to pass.
Absolutely the best heads are the NEWEST heads.

R&R/ing heads is simply take everything off, clean up the block and put everything back again where it was in the first place.

Since everyone has a camera in their pocket these days, I suggest taking many pictures before you start. Then clean off a PLACE counter or floor or somewhere. Even the bed of the truck. Then as things are taken off place them IN ORDER so they can be rep[laced in that order. Especially the rockers and pushrods. I always put these back in the same location with the rod even in the same direction. This mates them back where/like they have become familiar.
For sure I would put a new coolant pump in there.

Oh yeah! The dist gives lots of guys problems when putting it back together. BEFORE beginning take the cap off and bump the starter to get the rotor pointed directly to the No.1 spark!! This is a MUST DO for novices. (me too!)
When you do get her apart put some photos on here to show us the offending valves/heads or even the block itself might be the culprit.
Big Jim

 

[kb406]

Thanks, Jim. Great tips! Not sure I fully understand the distributor tip, though. The 98 ranger has an ignition coil pack, not a distributor. Does your tip still apply?

If so, I want to fully understand what to do. I take off the ignition coil cover, and give the starter a good solid thump. And that will get it pointed at No. 1 spark? Seems simple, but important enough to get it right.

 

[kb406]

Ran the glove test and a compression test, and Im a bit confused by the results. Want to verify that I did everything correct.

With a cold engine, attached a condom to the rad cover hole. Disconnected the overflow hose, to make sure air was not getting in through a crack in the overflow tank or overflow hose. Started truck and plugged overflow outlet at radiator cap. Condom inflated, but very, very slowly. Seems to indicate a possible head gasket leak. Any chance it could instead be an intake manifold gasket issue? I am starting to see possible signs of coolant in the oil.

For the compression test, I also started with a cold engine (is that bad?). I removed all of the spark plugs. Then threaded the compression tester into each cylinder and cranked to max pressure. The results are not great:


Cylinder 1: 80
Cylinder 2: 55
Cylinder 3: 0
Cylinder 4: 65
Cylinder 5: 95
Cylinder 6: 95

Coolant sprayed out of Cylinder 3, and it had zero compression. So theres definitely a blown hg at number 3. But the low numbers on all the other cylinders are troublesome as well. Any chance I performed the test wrong? The engine was cold, and I did leave the condom on the rad instead of the cap. The truck does not drive like it is this bad.

If it wasnt my error, then it may be bad piston rings? Poured a tbsp of oil into cylinders 1 and 4 and retested, both jumped up to about 120. Does this confirm bad piston rings?

Not sure where this leaves me. Really wanted to begin the engine disassembly today, but second guessing that now. If piston rings are bad, should I just find a used engine to swap in? Are there likely other issues, like cracked pistons or bad valves, waiting to be found?

Thanks for all the help so far!