Overheated & Leaking - What to replace?
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Overheated & Leaking - What to replace?
First post! Love the little truck, 2000, Ranger, 4.0L, Auto, 4x4, etc. Only have a couple of irritating items like a constant jingle/rattle that sounds like something loose in the tranny as I drive down the highway and a window that is jerky as I roll it up and down.
However, my main problem though is that it overheated back in October and has been leaking coolant. Thermostat stuck closed so it pegged the temp guage and then After it cooled down, I pulled the t-stat and drove it home. I replaced the t-stat the next day and it has run fine and held temp ever since. However, I have had the sweet rad fluid smell and coolant is disappearing. Finally had a chance to get up underneath it and I see it is seeping from between the heads and block. I did change the oil and it looked fine and the amount was about the same as I always have after 3k miles where it is about 1 quart low. I am assuming the heads either warped or cracked and was planning on purchasing a set of new assembled heads for about $400. I figured this is cheaper than having both heads disassembled and magnafluxed, flattened and then reassembled. Particularly if one or both end up being cracked. I know about the head bolts being TTY and of course, new gaskets. What else? My main concern is what are the chances the block deck needs work? Is this a common problem with these engines where the heads warp or crack so easily after overheating? Thanks.
Any links to sites that can help with the replacement procedure as well would be appreciated. I tore apart the SOHC 4.6 in my '98 GT and put new heads, intake, timing chains on it but haven't worked on an OHV engine before. Of course, the Haynes manual or a ford service cd will be along for the trip.
However, my main problem though is that it overheated back in October and has been leaking coolant. Thermostat stuck closed so it pegged the temp guage and then After it cooled down, I pulled the t-stat and drove it home. I replaced the t-stat the next day and it has run fine and held temp ever since. However, I have had the sweet rad fluid smell and coolant is disappearing. Finally had a chance to get up underneath it and I see it is seeping from between the heads and block. I did change the oil and it looked fine and the amount was about the same as I always have after 3k miles where it is about 1 quart low. I am assuming the heads either warped or cracked and was planning on purchasing a set of new assembled heads for about $400. I figured this is cheaper than having both heads disassembled and magnafluxed, flattened and then reassembled. Particularly if one or both end up being cracked. I know about the head bolts being TTY and of course, new gaskets. What else? My main concern is what are the chances the block deck needs work? Is this a common problem with these engines where the heads warp or crack so easily after overheating? Thanks.
Any links to sites that can help with the replacement procedure as well would be appreciated. I tore apart the SOHC 4.6 in my '98 GT and put new heads, intake, timing chains on it but haven't worked on an OHV engine before. Of course, the Haynes manual or a ford service cd will be along for the trip.
Posting Guru
Joined: Jun 2003
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A couple of things to think about. I don't like buying parts till I know what I need. It could just be a head gasket, those 4.0l are pretty tuff. Also I think I would get some leak detector for the cooling system if there is any chance your not sure of where its leaking. If you did a SOHC motor you shouldn't have any problems doing the ohv motor.
Dave
Dave
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Joined: Jan 2003
Posts: 9,748
Likes: 16
From: Connecticut
With the Ford CD and even the Haynes Manual you should be able to do it.
As for whether or not the block is going to need work, that's a tough call. I suppose a lot depends on how severe the overheating event was. You're going to have to make the call once in your in there.
The 4.0L is not as prone to cracking heads as it's predecesor, the 2.9L, but I can't say that I haven't read a few posts about 4.0L cracked heads, either.
As I understand it, Ford has updated it's 4.0L OHV headgaskets over the years, I would assume they are of good quality, as Ford OEM gaskets usually are.
A good article on the 4.0L can be found here, there are some things to think about regarding a rebuild to any degree: http://www.babcox.com/editorial/ar/ar40123.htm
Maybe someone else will come along with some detailed insight. Good luck with the repair.
As for whether or not the block is going to need work, that's a tough call. I suppose a lot depends on how severe the overheating event was. You're going to have to make the call once in your in there.
The 4.0L is not as prone to cracking heads as it's predecesor, the 2.9L, but I can't say that I haven't read a few posts about 4.0L cracked heads, either.
As I understand it, Ford has updated it's 4.0L OHV headgaskets over the years, I would assume they are of good quality, as Ford OEM gaskets usually are.
A good article on the 4.0L can be found here, there are some things to think about regarding a rebuild to any degree: http://www.babcox.com/editorial/ar/ar40123.htm
Maybe someone else will come along with some detailed insight. Good luck with the repair.
Tuned
Joined: Jul 2007
Posts: 289
Likes: 0
From: So. Cal.
New link for post #5. The link for babcox doesn't work. Rebuilding The Ford 4.0L Pushrod V6: Engine Builder
