HI guys,

I restored a 1987 F150 4.9L Custom.
I start the engine and within seconds, I have liquid dripping out of the the exhaust.
https://www.screencast.com/t/dWMdqwj5Tyw

As the engine heats up, white smoke starts coming out of the exhaust as well. not a crazy amount, but enough that is noticeable.
It is about 68F outside today so its not condensation.


There is also a small but noticeable amount of white smoke come from the rear of the engine block.

There is no white crap under the oil cap, no coolant a the base of the spark plugs.

Is what I am describing enough to diagnose a head gasket issue?
I dont mind ordering the parts, but I want to be sure before I have to take this engine apart.

It really sucks because I just got done replacing the Exhaust manifolds, and putting in a new Valve cover gasket...
So like I said, I really want to be sure before having to take this engine apart again...

Thanks in advance for any advice,

Denis

 

Question, could these symptoms simply be intake manifold leak? as I said, I replaced the Exhaust manifold so had to remove both the intake and exhaust manifold.
I did not replace the upper intake manifold gasket because it looked fine.

1. Maybe the gasket needs to be replaced
2. Maybe I didnt get the torque right on the bolts.
3. Maybe I messed something up in the reassembly of the manifolds.

Thoughts? comments?

Denis

 

Was the engine just assembled? Mileage is?
Or just the truck is being restored?

If it’s not condensation being exhaled (condensation will clear up under normal heating), with coolant dripping and white smoke exiting the pipe, it must be bleeding into the cylinders. Most often the system level will continually drop if a bleed or leak.

If a head gasket, head crack, or cylinder itself, generally you’ll see air bubbles in the radiator fill, engine running or under added test pressure. A block/cylinder crack generally will pollute the oil easier than the two other possibilities.
This is where a cylinder leak down tester or even simple shop air added to each cylinder can help to quickly pinpoint or prove out an internal bleed without running the engine. Then if torn down, the cylinder or area in question may be quicker to ID
A cooling system pump type pressure tester can help with a HG or crack diagnosis as well. If a crack or HG failure,, cooling system pressure won’t be able to be maintained as pressurized coolant is forced through the leak.
Leaving the system pressurized, spark plugs out, then cranking the engine over may produce coolant being expelled from the plug holes proving out a failure. Shop air or a leak down test would quickly produce system bubbling...

Coolant/antifreeze when combustion burned will produce plumes of white smoke that doesn’t dissipate easily (like condensation does) and has a sweet smell.

There’s not too many places coolant can get into the exhaust, and the puff at the rear may be an exhaust leak producing another visual leak point.

 

I fixed it!
The engine only has 109k KM.

I checked the torque specifications for the upper intake Manifold to lower (18FT /LBS) and the lower intake manifold to Engine Header (26FT/LBS).
Then torqued all bolts to those specs and after 5 minutes idling, liquid stopped coming out of the exhaust pipe and there is no longer any smoke coming out of the rear of the engine block!

God so happy I dont have a busted head gasket!
Lesson learned, torque to specs!

Hope this helps someone else!

denis