98 Exp 4.0 OHV Coolant Loss/leak, Misfire, Cylinder Head Advice

[Betsy98Sport]

Hi. I'm about to replace the upper engine gaskets on my 98 explorer 4.0 OHV.The car has about ~160,000 or 120,000 on the block since it's a rebuild I had put in Dec 2004. Since I'm taking the heads off I wanted to take them to a machine shop and have them inspected.

By the way. The main job I'm doing is replacing the head gaskets. After looking through many threads I decided to do this.

Symptoms:

My 4.0 OHV was loosing coolant in the reservoir each day at a slow rate. I keep replacing coolant and it keeps going down. It's been like this for about a year now. I found a leak coming from what I thought was the timing chain cover on the passenger side. I replaced the gaskets on the timing cover and the water pump with Ultra Black RTV and the leak was still there. I found that the leak seems to be coming from the lower intake to head region and also leaking down the passenger side of the block by the exhaust manifold.

There's a noticable stumble/vibrating rumble when the engine is first started cold and when I accelerate or are under load. There is white smoke coming out the tail pipe when first started and goes away after a minute or two of warm-up. The tail pipe also drips a lot when the white smoke comes out. The PCM has spit out P0303 cylinder 3 misfire, and P0171 system too lean (bank 1).

I've done a compression test a few times over the last few months and all the cylinders check out well. However, about 3 months ago when doing a compression test all the cylinders were within 5 psi of 170, but cylinder 3 read 145 the first time then 155 then 160 (I will post these results if needed). The spark plug in clyinder 3 was coated in a red rusty color as well. I ended up replacing the Autolite platinums with Bosch Platinum 4+. Didn't help any.

The last thing is that I have had to frequently flush the cooling system every few months because the coolant ends up turning rusty red with a green tint after a while (possible mixing of oil and coolant). The dipstick always reads higher than the max mark even after oil changes with 5qts and new filter

I'm replacing the exhaust, lower intake, fuel rail, upper intake, etc. I purchased the Fel-Pro head gasket set (Part #HST9081PT1) and new head bolts.

Anybody have a list for all the gaskets included? I know most of them except the circular one at the top right and the other two circular ones bottom left

Anybody know any good and fair priced machine shops in San Diego. And also any advice on what to ask to be done for the inspection at the shop would be great. Or also any confirmation on my thoughts or advice Thanks.

I think I'm going to do coolant pressure test on Monday.

 

[Betsy98Sport]

bump

 

[Gabe96Explorer]

Don't use Bosch stuff in these trucks... Bosch stuff is GARBAGE. Ford recommends MOTORCRAFT and MOTORCRAFT ONLY, you were better off with the Autolite stuff.

Your getting rusty coolant because someone ran it with tap water and not distilled water when they decided to sub out for coolant. Run Cooling system flush or get it flushed professional with a Positive pressure system.

You are most certainly burning coolant with the white smoke... has it ever over heated ONCE?

 

[Betsy98Sport]

Don't use Bosch stuff in these trucks... Bosch stuff is GARBAGE. Ford recommends MOTORCRAFT and MOTORCRAFT ONLY, you were better off with the Autolite stuff.

Found out about this just recently. Will change while doing the gaskets.

Your getting rusty coolant because someone ran it with tap water and not distilled water when they decided to sub out for coolant. Run Cooling system flush or get it flushed professional with a Positive pressure system.

When I first did a flush in 2005 and in 2007 I think I used tap water. I didn't know then. I used distilled after that.

You are most certainly burning coolant with the white smoke... has it ever over heated ONCE?

It got close to overheating when I accidentally forgot to replace a cap on the heater hose after backflushing. I was able to stop and fill it. But that happened only a few months ago and I've had this issue for the last year or so

 

[iwannabamedic]

I completed mine a 2000 ex 4.0 OHV heads pressure checked and valves grind. The pic you have posted is all you need to replace both heads and intake.
The hardest part I had when doing mine was the exhaust manifold and manifold to pipe. I had to drill them out, they would not move, or broke, PB blaster and heat did nothing. get the exhaust manifold checked if you have problems. take your time when re installing
was not that bad. I used the motor-craft platinum plugs
as far as finding a machine shop ask some of the auto parts stores or garages.
good luck

 

[Betsy98Sport]

I washed off the block and turn on the car again. I revved up the engine to increase the pressue in the coolant system. Sure enough I saw coolant seeping out from where the head gasket seam is.

The leak is where the two arrows are pointing on the bottom left right on the seam:

Im going to do a pressure test today as well to see if it does it when. But Im sure it's a leaky head gasket or possibly even a lower intake gasket. Either Im replacing all the gaskets with the head gasket set and Ultra Grey RTV.

Also last night, I looked at the compression test I did last and I noticed that 1,2 and 3 cylinders all had lower compression readings by about 15psi. I didn't mention it before because they still fell within 10% of the others.

Any thoughts? Also still looking for reputable and reasonable machine shop to inspect the heads if anyone knows of one in San Diego.

I'll see If I can get pics. My camera is not working right now.

 

[ranger7ltr]

I was in the same situation recently...

My 1999 OHV engine was losing coolant from a head gasket to the tune of a pint a month...Even though I lived with this for a year and a half, I finally got tired of the odor and the leak and removed the heads...I had new heads from when I bought the truck so I wasn't going to even care about the old ones...If I hadn't found a couple of bad cylinder walls I would still be using that block...

One thing about this project; When you need to machine shop the heads, do not be surprised when they come back cracked...Ford v6 heads are notorious for that...And the machine shop will charge you for the work they did usually even if the castings are not useable...

That is why I bought new heads when I first bought the truck even though I did not use them for 18 months...The cost of the complete heads was $325.00, shipping included, and no cores to return...

And don't forget that you will need new head bolts for this engine...The Ford head bolts are torque to yield and you cannot reuse them for head bolts...I actually got the head bolts and a complete head gasket set from the same vendor I bought my heads from for $ 95.00 when I bought my heads...

Back to your original question on the gaskets...You have a gasket for the throttle body to the plastic upper intake...Your other round gaskets are the EGR pipe o-ring, I believe dipstick o-ring, IAC double o-rings and EGR pipeto EGR valve gasket...

I do have one question for ya; What shape are the rockers, pushrods, and lifters in? Since I had the top end off I replaced the lifters and the rockers which seemed pretty chewed up on the pushrod and the valve ends...I replaced the rockers and pushrods for $99.00 and the lifters which were remanufactured for around $110.00...I am glad I replaced them both after looking at the old ones...

 

[Betsy98Sport]

My 1999 OHV engine was losing coolant from a head gasket to the tune of a pint a month...Even though I lived with this for a year and a half, I finally got tired of the odor and the leak and removed the heads...I had new heads from when I bought the truck so I wasn't going to even care about the old ones...If I hadn't found a couple of bad cylinder walls I would still be using that block...

One thing about this project; When you need to machine shop the heads, do not be surprised when they come back cracked...Ford v6 heads are notorious for that...And the machine shop will charge you for the work they did usually even if the castings are not useable...

That is why I bought new heads when I first bought the truck even though I did not use them for 18 months...The cost of the complete heads was $325.00, shipping included, and no cores to return...

And don't forget that you will need new head bolts for this engine...The Ford head bolts are torque to yield and you cannot reuse them for head bolts...I actually got the head bolts and a complete head gasket set from the same vendor I bought my heads from for $ 95.00 when I bought my heads...

Back to your original question on the gaskets...You have a gasket for the throttle body to the plastic upper intake...Your other round gaskets are the EGR pipe o-ring, I believe dipstick o-ring, IAC double o-rings and EGR pipeto EGR valve gasket...

I do have one question for ya; What shape are the rockers, pushrods, and lifters in? Since I had the top end off I replaced the lifters and the rockers which seemed pretty chewed up on the pushrod and the valve ends...I replaced the rockers and pushrods for $99.00 and the lifters which were remanufactured for around $110.00...I am glad I replaced them both after looking at the old ones...

Where did you make these purchases? Internet? Local business?

 

[ranger7ltr]

There are a couple of vendors I got parts from...

The cylinder heads are from J & C Cylinder Heads...

New 4.0 liter Ford heads..

http://cgi.ebay.com/ebaymotors/NEW-...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

Remanufactured lifters, rockers, and pushrods are from Specialy Engine Parts..

Remanufactured lifters...

http://cgi.ebay.com/ebaymotors/4-0-...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

Rockers and pushrods...

http://cgi.ebay.com/ebaymotors/4-0-...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

This vendor also has quite a few Ford 4.0 liter parts and if you buy multiple items from them, they will combine shipping... Just remember to email or call them to combine shipping...

 

[Gabe96Explorer]

ARP or Ford OEM for head bolts please...

 

[Betsy98Sport]

ARP or Ford OEM for head bolts please...

I purchased Fel-pro gasket set (HST9081PT1) and head bolts (ES72794). Is it really that big a difference?:scratch:

 

[jds3403]

Not to crap in your pot but the 2.9 and 4.0 heads are notorious for cracking and leaking coolant into the engine, most of the time into the crankcase and occasionally into a cylinder as well, sounds like #3 for you had some water hence the rust, (and maybe the rings had surface rust hence the low compression that bounced back probably due to piston movement and oiling); me personally if you are mechanically inclined it will cost you about 650.00 bucks parts and gaskets to really fix the problem, replcae both heads and be done with it. Don't do a bandaid repair to find out that it didn't fix it and now you are out even more. IMO Go to alabama cylinder head 205 a piece fully assembled you got the right gaskets and bolts get the oil and anitfreeze you need and get it done, I've done this more than I care to count on a few 4.0's and it really isn't that bad, last one I did I completed in a day sun up to sun down, costs about 650.00 and you can have it done in a day and be done with it for good, and remember water doesn't make a good lubricant!!!

 

[jds3403]

And fel pro makes the bolts too I believe and they work just fine I think the final torque ends up being 95 ftlbs. They actually torque to like 55 or something and then an additional 90 degrees which ends up being mostly 95 foot pounds, the bolts that I use that you get from advance auto or auto zone are more than capable of handling it.

 

[jds3403]

And delta cams makes a good remaned complete rocker arm set they have hardened tips and the pushrods they sell are hardened as well, I get remaned lifters from MIZPAH machine for 120-150 and they are excellent quality. compare that to new ones ha ha ha.... thats a funny one ford..... jackasses. the reason I am saying this is because the upper valve train IS worn out, due to fords crappy oiling design, highly recommended to replace atleast the pushrods to the rocker arm assembly, the lifters are probably fine as they are hyd roller lifters and can take the abuse atleast from what I've seen, but it is all up to your comfort level of what you can do and what you can live with when you sleep at night. Me personally I am an **** SOB. sorry for the hijack

 

[Betsy98Sport]

No prob on the hijack jds3403. It's all good info. My neighbor who's a mechanic suggested the same at least as far as the issues with the heads. He said he's done the same thing on an Explorer before.

I'm really thinking about getting new heads now to save me the trouble of depending on a machine shop.

Anyone else agree to this about getting new heads? I'm not sure about getting the pushrods, rocker assembly and/or lifters though. Any thoughts?

Also anyone know the part number/code or type of head that's for my 98 Exp Sport 4.0 OHV.

 

[ranger7ltr]

Here's my take on this project...

I too had a coolant leak from the head gasket area...I started off to just r & r the heads, top end gaskets, and rebuilt fuel injectors I had... I didn't want to run the hassle of removing the heads, taking them to a machine shop, then finding out they were useless...New heads were actually less than rebuilt heads and I didn't have to wait on them...And I wanted to work with new castings and going new was the only obvious solution for me...PS i have the old heads if anyone wants them to play with...They are dirty but might not be cracked...

When I pulled the heads, I found a couple of cylinders damaged so that shortblock was done and removed and a remanufactured Motorcraft shortblock went into the engine bay...

Now since the engine was open and you have to remove the heads to replace the lifters I was going to perform that task as well...When I looked at the rocker arm tips and the pushrod sockets and saw they were chewed up pretty well, I decided to go with replacement parts on the top end...

My shortblock was completely new and I had new heads from J&C cylinder heads so the decision to replace the rest of the internals was not difficult...Especially after seeing the condition of the rockers and pushrods...The only difference was I replaced the rocker assembly and pushrods when i was only planning to replace the heads and lifters...

Frankly, even with the original shortblock, when I would have looked at the rockers and seen the damage, I would have replaced them and the pushrods anyway... It was just that with the added cost of the new shortblock, I was not going to take any chances with all the other new/rebuilt components in the engine...

Oh and I did replace the harmonic balancer and the water pump; water pump due to age and balancer due to cracks in the rubber ring...

 

[jds3403]

pulled from the TRS tech library,

HEADS
There have been three distinctly different heads with five different casting numbers installed on the 4.0L since 1990. The combustion chamber was changed in ’95 and the exhaust ports were revised in ’98.

1990-’94 All and ‘95-’96 Aerostar
The original 90TM casting had an oval-shaped chamber that was slightly bigger in diameter on the intake side. It was replaced in ’93 by the 93TM-AA casting that was exactly the same. These heads can be identified by the letter "T" located on the top of the right rear/left front exhaust port.

1995-’97 Ranger, Explorer and ’97 Aerostar
The 95TM-AD casting that came out in ’95 had the heart-shaped, fast-burn chambers that shrouded the intake valves. It was replaced by the 97TM casting in ’97, but it was the same, so they can be used interchangeably. These castings were used on the Ranger and Explorer from ’95 through ’97 and on the Aerostar in ’97. They can be identified by the letter "U" that’s located on the top of the right rear/left front exhaust port.

1998-2000
Ford introduced another new head in ’98. The exhaust ports on the 98TM-AD were much narrower than they were on the earlier castings; they measured 1.40˝ across the port compared to 1.70˝ on the 95TM/97TM castings. According to the engineers I have talked to, the smaller ports increased the velocity of the exhaust gasses so they carried more heat down to the catalytic converter. This helped the converter “light off" sooner, so it did a better job of reducing emissions during the critical start-up and driveaway phase of the EPA emissions test. With that in mind, it’s probably not a good idea to swap these heads back and forth with any of the earlier castings. (TRS)

You'll want the 98tm castings, you can go with the 95tm castings as the only difference is the exhaust port, 98tm it is narrower as mentioned above to help with emissions but the bowls are the same, I've used 95tm heads on 98 and above trucks before with no problem what so ever, you can't really tell a difference in power and the oldest has lasted for over 70K miles so far with no problems, and again I would absolutely recommend than you replace the upper valve train, does your motor make a constant marble noise? does it sound like a constant ticking coming from all over the motor and multiple ticks sound rolled into one? if so the pushrod tips and rocker arm cups are trash just my two cents

 

[ranger7ltr]

x2 on the 95tm castings...

I used them on my new 99 shortblock and I actually port matched the exhaust manifold to the exhaust port...Exhaust ports are 1.70" vs 1.40"...Did the same on the lower intake manifold to the intake ports...

Difference in power? Couldn't tell ya...But combined with the exhaust work I did after the manifolds it might make some difference...

I removed the flange from the headpipes as it is configured as 2 pipes dumping into the front of the first catalytic convertor and installed an x-pipe...Then I continued out from each leg of th ex-pipe to a single hi flow cat on each pipe then into a dual in-dual out Magnaflow muffler then 2 tailpipes out the back of the truck...

I am also running 2 hi flow cats in the headpipes and I had the o2 sensors mounted in the standard spot in the headpipes... The secondary cats have o2 bungs on the outlet side so I installed the last o2 sensor in one of the secondary cats... I capped the other cats' o2 sensor hole ...

I opened up the manifolds to the heads' exhaust and intake port size to allow a bit more airflow through the system and I used 2.25" exhaust piping from front to back...Man I love the throttle response and the new engine, while still being broken in, has more power than the original engine ever thought about...

 

[Betsy98Sport]

You'll want the 98tm castings, you can go with the 95tm castings as the only difference is the exhaust port, 98tm it is narrower as mentioned above to help with emissions but the bowls are the same, I've used 95tm heads on 98 and above trucks before with no problem what so ever, you can't really tell a difference in power and the oldest has lasted for over 70K miles so far with no problems, and again I would absolutely recommend than you replace the upper valve train, does your motor make a constant marble noise? does it sound like a constant ticking coming from all over the motor and multiple ticks sound rolled into one? if so the pushrod tips and rocker arm cups are trash just my two cents

Yes. That noise! Oh my goodness. I've been thinking about what the noise for the longest. At first I thought it was the clutch area but then I narrowed it down to the engine bay. After reading through threads and your thoughts, that's got to be the sound that irritates me all the time.

Thanks for the info jds3403 and ranger7ltr. I believe I will go with new heads. I'm afraid of the old ones cracking after being machined. The rocker arms and pushrods will probably be done as well.

1. Is it really important to have the lifters replaced?

2. Do I need replace all pushrods and the whole rocker assembly or can I replace as needed based on wear?

3. ranger7ltr, what do you think about the quality of the heads you got from J&C? What did you mean by "...I actually port matched the exhaust manifold to the exhaust port...Exhaust ports are 1.70" vs 1.40"...Did the same on the lower intake manifold to the intake ports..."? What did you actually do?

4. Anyone else purchased the cylinder heads from J&C Enterprises? Reviews?

I'm asking these questions for quality control and just to be sure I'm making the right or at least best move every step of the way?

I'm trying to be cost effective and even the thought of new heads is making me say, "oh boy." But if it's truly worth it then I'll save up for it. I'm married so I'm thinking about the wife too if you married folks know what I mean.

Lastly, when I'm ready to go I will posting pics and DIY info so everyone can see and find info they need.

 

[Betsy98Sport]

Back to your original question on the gaskets...You have a gasket for the throttle body to the plastic upper intake...Your other round gaskets are the EGR pipe o-ring, I believe dipstick o-ring, IAC double o-rings and EGR pipeto EGR valve gasket...

These are the ones I'm not sure about in the Fel Pro Gasket Set. I think the round black one to the right is the thermostat housing gasket, but not sure.

Anyone know which is which?