4.0 SOHC good compression, but coolant in cylinders

[jpfunjunky]

Hello everyone. I’ve stalked these forums enough it should be illegal but finally need help and advice!
I recently purchased a 2004 Sport Trac Adrenalin 4.0 SOHC for my kid. It has 113,000 miles and is clean inside and out. It didn’t run and previous owner said he was having the typical overheating issues from the plastic thermostat housing and replaced it with an aluminum aftermarket, as well as put in a new radiator. Of course he claimed it never ran real hot but who knows. For 1,000 dollars the shady tree mechanic in me couldn’t pass it up!
Problem is there was a good bit of moisture in almost all the cylinders when I pulled the plugs. They were wet and smelled like gas but wouldn’t light with a cig lighter. I pulled the fuel pump relay and we tested for compression on all but the impossible to reach #3 cylinder and they all tested well at around 180 psi.
Decided to drain all of the coolant from the engine (to prevent coolant from entering cylinders), bought and installed new plugs and wires and she fired right up! Ran good from what I could tell, except some steamy/smoky exhaust. We didn’t run it long at all though, so I don’t know if the exhaust would clear up or not.
I researched and found that coolant can enter the lower intake manifold, so kiddo and I pulled the intake and there is no lower manifold that I can see, and no way for coolant to get in. So I’m stumped and need help!
I do believe the new thermostat housing that was installed was leaking. It has a really cheap O-ring that seemed flattened. Prior to draining the engine, when cranked/wouldn’t start, some coolant was coming down from that area. I couldn’t quite tell where it was coming from, but can’t see how it would get into the cylinders when the SOHC has an elevated connection point for the intake.
What am I missing?

Sorry for the long post!

 

[Lee's Automotive]

Hello everyone. I’ve stalked these forums enough it should be illegal but finally need help and advice!
I recently purchased a 2004 Sport Trac Adrenalin 4.0 SOHC for my kid. It has 113,000 miles and is clean inside and out. It didn’t run and previous owner said he was having the typical overheating issues from the plastic thermostat housing and replaced it with an aluminum aftermarket, as well as put in a new radiator. Of course he claimed it never ran real hot but who knows. For 1,000 dollars the shady tree mechanic in me couldn’t pass it up!
Problem is there was a good bit of moisture in almost all the cylinders when I pulled the plugs. They were wet and smelled like gas but wouldn’t light with a cig lighter. I pulled the fuel pump relay and we tested for compression on all but the impossible to reach #3 cylinder and they all tested well at around 180 psi.
Decided to drain all of the coolant from the engine (to prevent coolant from entering cylinders), bought and installed new plugs and wires and she fired right up! Ran good from what I could tell, except some steamy/smoky exhaust. We didn’t run it long at all though, so I don’t know if the exhaust would clear up or not.
I researched and found that coolant can enter the lower intake manifold, so kiddo and I pulled the intake and there is no lower manifold that I can see, and no way for coolant to get in. So I’m stumped and need help!
I do believe the new thermostat housing that was installed was leaking. It has a really cheap O-ring that seemed flattened. Prior to draining the engine, when cranked/wouldn’t start, some coolant was coming down from that area. I couldn’t quite tell where it was coming from, but can’t see how it would get into the cylinders when the SOHC has an elevated connection point for the intake.
What am I missing?

Sorry for the long post!

I would replace the intake gaskets since you already removed the intake and seal up the aluminum tstat housing and let the engine run to burn off any moisture in the engine also how does the oil and coolant look is there oil in the coolant? and is there any coolant in the oil?

 

[Josh P]

Once you seal up the cooling system, pressure test it, and use a laser thermometer on the exhaust manifolds. Any coolant in a cylinder won't heat the exhaust as fast as the others on initial startup.

 

[jpfunjunky]

I would replace the intake gaskets since you already removed the intake and seal up the aluminum tstat housing and let the engine run to burn off any moisture in the engine also how does the oil and coolant look is there oil in the coolant? and is there any coolant in the oil?

I checked all the usual places, radiator cap, inside the radiator and reservoir and there was no oil or froth. The oil also checked out clean, even after we ran it for a bit.
We may try putting all back together and letting it get up to temp and see what happens. I just can’t figure out why there was so much moisture (that I assume was coolant)
The motor almost acted hydrolocked before we pulled the plugs. It turned over but was sluggish. Then there was quite a bit of liquid and mist spurting out and it felt like coolant and smelled like gas.
All the original owner could tell us was that it never got real hot, and that it wouldn’t start after he put the new radiator and tstat housing in it.

 

[Lee's Automotive]

I checked all the usual places, radiator cap, inside the radiator and reservoir and there was no oil or froth. The oil also checked out clean, even after we ran it for a bit.
We may try putting all back together and letting it get up to temp and see what happens. I just can’t figure out why there was so much moisture (that I assume was coolant)
The motor almost acted hydrolocked before we pulled the plugs. It turned over but was sluggish. Then there was quite a bit of liquid and mist spurting out and it felt like coolant and smelled like gas.
All the original owner could tell us was that it never got real hot, and that it wouldn’t start after he put the new radiator and tstat housing in it.

Honestly id seal it up and let it run most likely it's moisture because id expect coolant in the oil or sweet smelling exhaust if it was a head gasket

 

[Lee's Automotive]

I checked all the usual places, radiator cap, inside the radiator and reservoir and there was no oil or froth. The oil also checked out clean, even after we ran it for a bit.
We may try putting all back together and letting it get up to temp and see what happens. I just can’t figure out why there was so much moisture (that I assume was coolant)
The motor almost acted hydrolocked before we pulled the plugs. It turned over but was sluggish. Then there was quite a bit of liquid and mist spurting out and it felt like coolant and smelled like gas.
All the original owner could tell us was that it never got real hot, and that it wouldn’t start after he put the new radiator and tstat housing in it.

You could also pressure test the cooling system as Josh mentioned above

 

[Josh P]

How long has the vehicle sat before you bought it?

 

[jpfunjunky]

Once you seal up the cooling system, pressure test it, and use a laser thermometer on the exhaust manifolds. Any coolant in a cylinder won't heat the exhaust as fast as the others on initial startup.

I just might give that a try! Any suggestions on how to pressure test and what psi to aim for?
Thanks for your help

 

[Lee's Automotive]

I just might give that a try! Any suggestions on how to pressure test and what psi to aim for?
Thanks for your help

Whatever psi is on your radiator cap

 

[Josh P]

I just might give that a try! Any suggestions on how to pressure test and what psi to aim for?
Thanks for your help

About 15 psi is good. Harbor freight sells a tester you attach where the radiator cap goes. Also good to start the engine if it holds pressure to see if the needle dances while running.

 

[jpfunjunky]

How long has the vehicle sat before you bought it?

According to seller it was less than two months

 

[Lee's Automotive]

According to seller it was less than two months

with you being in Florida and having high humidity it makes sense to have condensation from the tail pipe when the humidity is over 80% here in bama my X produces steam on cooler days which is normal

 

[jpfunjunky]

with you being in Florida and having high humidity it makes sense to have condensation from the tail pipe when the humidity is over 80% here in bama my X produces steam on cooler days which is normal

It’s very humid here and steamy exhaust is definitely normal for a bit, but I’ve never seen a motor not run just because of moisture condensing in the cylinders. Is that even possible? I just assumed head gaskets until I had good compression…

 

[Lee's Automotive]

It’s very humid here and steamy exhaust is definitely normal for a bit, but I’ve never seen a motor not run just because of moisture condensing in the cylinders. Is that even possible? I just assumed head gaskets until I had good compression…

Honestly im not sure what caused that either but if theres coolant in the cylinders id expect a sweet smell and running rough or a misfire

 

[Josh P]

It’s very humid here and steamy exhaust is definitely normal for a bit, but I’ve never seen a motor not run just because of moisture condensing in the cylinders. Is that even possible? I just assumed head gaskets until I had good compression…

If he couldn't get it started for whatever reason, the cylinders will fill up with gas. There will be moisture mixed with that if it sat for several months.

 

[Lee's Automotive]

If he couldn't get it started for whatever reason, the cylinders will fill up with gas. There will be moisture mixed with that if it sat for several months.

Exactly what i was just thinking basically no start but injectors still spraying fuel in the cylinders and that caused it to have moisture and be hard to turn over because of that fuel in the cylinders

 

[Josh P]

Exactly what i was just thinking basically no start but injectors still spraying fuel in the cylinders and that caused it to have moisture and be hard to turn over because of that fuel in the cylinders

It takes a lot of attempts of a no start to get to this point. Had it happen to my friends 89 F250 with a 460. Guy he used to work for stole his truck and hid it. We found it and went to recover it at midnight, Would not start, we eventually figured out the spark plug wires were rearranged on the cap. There was gas running out the exhaust. It lit up the sky when it finally fired up.

 

[Lee's Automotive]

It takes a lot of attempts of a no start to get to this point. Had it happen to my friends 89 F250 with a 460. Guy he used to work for stole his truck and hid it. We found it and went to recover it at midnight, Would not start, we eventually figured out the spark plug wires were rearranged on the cap. There was gas running out the exhaust. It lit up the sky when it finally fired up.

Wow that's messed up and crazy, I bet the guy kept cranking it until it started to slow down due to fuel being in the cylinders and that's when he gave up and thought it was a head gasket

 

[jpfunjunky]

Exactly what i was just thinking basically no start but injectors still spraying fuel in the cylinders and that caused it to have moisture and be hard to turn over because of that fuel in the cylinders

Definitely hadn’t thought about the old fuel being the culprit… it just seemed too watery with an oily texture.

 

[Josh P]

Definitely hadn’t thought about the old fuel being the culprit… it just seemed too watery with an oily texture.

The new gas doesn't stay gas for very long