1994 Ford Explorer XLT 4X4 issues

[michael.robinson]

Ok i have this explorer i got from my mother. I drove it 277 miles with no problems. When i got home with it it started fine while i recharged the a/c system. During idle while i was waiting to check everything out the upper radiator hose exploded so i shut the motor off. I replaced the hose the following day. After the repair i started it and drove it around the neighborhood with no problems. When i stopped at the drive way and let it idle for a few minutes it started knocking sounding almost like a diesel truck running. When i gave it a little gas to rev the engine thinking maybe something was sticking it stopped. I turned it off and let it sit for a little while. I went back out to start it a few minutes later it had a hard time trying to start and melted the positive battery clamp. It started in the process and idled fine but as soon as you put it into drive or reverse it started it again. I drove it to the corner store and on my way back to the house it died and shut off cause it was over heating. Im stumped and have no idea what this could be. If anyone could help me i would really appreciate it. It sounds like the knocking is coming from the front passenger side of the motor. Is it possible it could be transmission?

 

[michael.robinson]

After doing some real hard thinking and research. Is it possible that it could be the torque converter or flywheel?

 

[MrShorty]

I will not say that those aren't possibilities. However, if the noise is coming from the front passenger part of the motor, that doesn't seem like a transmission issue.

So what are the actual symptoms we are diagnosing? A clattering like valve train noise plus overheating??

If the two are related, I would first think cracked cylinder head, but they may not be related. Is it using coolant? Signs of coolant in the oil or in the exhaust? Because a cracked head will quickly take out the entire motor, I'd eliminate this possibility ASAP.

 

[Lbf119]

try your thermostat pull it out and then run it and see if the noise goes away.

 

[michael.robinson]

When i looked the other day to check everything i didnt have any oil in the radiator or anything. I couldnt really tell if there was any fluid in the exaust except for normal condensation that smells like water. I did notice that the radiator resivor is bubbling like air is coming from the tube off the radiator but i assumed that is normal. When i got underneath the truck and had my neighbor put it in drive it sounds like it could possibly be coming from the transmission but very hard to tell. It doesnt seem to be lossing any fluid either.

 

[MrShorty]

I did notice that the radiator resivor is bubbling like air is coming from the tube off the radiator but i assumed that is normal.

I don't think that's normal. There are usually two reasons you would get bubbling in the overflow. 1) overheating and the coolant is boiling over into the overflow or 2) cracked head or other way for cylinder gases to get into the cooling system.

 

[Tony H]

When i looked the other day to check everything i didnt have any oil in the radiator or anything. I couldnt really tell if there was any fluid in the exaust except for normal condensation that smells like water. I did notice that the radiator resivor is bubbling like air is coming from the tube off the radiator but i assumed that is normal. When i got underneath the truck and had my neighbor put it in drive it sounds like it could possibly be coming from the transmission but very hard to tell. It doesnt seem to be lossing any fluid either.

that screams head gasket.
The bubbles are the piston building up normal pressure in the cylinder, instead of it building compression, it's pumping air back into your coolant through a gasket breach.

 

[michael.robinson]

If it was a head gasket or a cylinder head issue wouldnt it make the noise constantly instead of only when its in reverse or drive.

 

[Tony H]

If it was a head gasket or a cylinder head issue wouldnt it make the noise constantly instead of only when its in reverse or drive.

The motor is under a bit more torque when it's in drive over when it's in nuetral.

I bet if you pull out the spark plugs , one will look Brand new Clean. That's your head gasket leaking coolant into that cylinder.

 

[michael.robinson]

Ok thanks everyone for all the help with the trouble shooting. Im replacing all the top end motor gaskets to see if there is any issues. I will post back when i get everything back together and running and see if it fixes my problem. I did notice a little corner in the intake manifold gasket that was broken around the water inlet to the heads. That could have been my problem but since i have it pulled apart im going to replace the head gaskets as well.

 

[michael.robinson]

Also the problem doesnt start until the motor is warmed up and it does the noise in park as well.

 

[MrShorty]

While you are replacing the head gaskets, I would suggest a careful inspection of the cylinder heads as well. I'm not sure which is more common (cracked heads or blown head gasket), but cracked heads are relatively common on this family of motor, and it would be a shame to dig this deep into the engine without at least checking the heads.