Coolant consumption

[fabianoliver]

Hello all !!
My 94 xlt manual transmission 140K miles, consumes coolant since i bought it 4 months ago.
Now is summer here, and the other day i needed to refill the radiator and expansion tank with half gallon ( 1,7 lts) after 280 miles mixed driving.
The fuel tank cap seems in good shape ( not too old), and cames with the truck. I don't know the bar specs of it ..
I don't see coolant speeled in the floor, or in the engine compartment, and i've never noticed a vapor pressure coming from the engine.....
The engine is running fine, and the truck is in very good condition now.
When i changed the plugs, the old ones seemed fine, at least at my eyes.
What can be the cause?, and how can i test to try to figure it out?
The temp gauge is fonctioning ok, and the needle stays always just befor the "N" letter.
Any advice is welcome
Thanks!!!

 

[410Fortune]

With flashlight check over the engine area very carefully looking for any coolant leaks external. After all hoses and clamps are ruled out

The lower intake manifold, freeze plugs, head gaskets, timing cover, thermostat housing and water pump are all suspect

After
Visual inspection you can use a coolant system pressure tester to add pressure to radiator and help spot leaks. You can add a dye to the coolant and use a light to spot any leaks.

It is quite possible you have a seeping head gasket or lower intake gasket and the coolant is being burned up in the combustion chamber
In fact any 93-94 ohv engine that is still on the road needs to have its intake and head gaskets replaced, age and wear tear will have caused a failed gasket by now for sure!!!
A small leak now will likely continue to grow
Careful inspection of the spark plugs can identify which cylinders are burning water
If the previous owner used a head gasket sealer it can wear off every season and the leak will return, more
Sealant would be added and the cycle continues

If you do determine that the leak is internal and not external you may consider some gaskets and cooling parts as preventive maintenance
I often Re seal ohvs
I can get reman heads out if Texas for $550 a pair including the return labels to return the cores. Along w new
Bolts and all new engine gaskets we can get many many miles from an old ohv 4.0

 

[Turdle]

With flashlight check over the engine area very carefully looking for any coolant leaks external. After all hoses and clamps are ruled out

The lower intake manifold, freeze plugs, head gaskets, timing cover, thermostat housing and water pump are all suspect

After
Visual inspection you can use a coolant system pressure tester to add pressure to radiator and help spot leaks. You can add a dye to the coolant and use a light to spot any leaks.

It is quite possible you have a seeping head gasket or lower intake gasket and the coolant is being burned up in the combustion chamber
In fact any 93-94 ohv engine that is still on the road needs to have its intake and head gaskets replaced, age and wear tear will have caused a failed gasket by now for sure!!!
A small leak now will likely continue to grow
Careful inspection of the spark plugs can identify which cylinders are burning water
If the previous owner used a head gasket sealer it can wear off every season and the leak will return, more
Sealant would be added and the cycle continues

If you do determine that the leak is internal and not external you may consider some gaskets and cooling parts as preventive maintenance
I often Re seal ohvs
I can get reman heads out if Texas for $550 a pair including the return labels to return the cores. Along w new
Bolts and all new engine gaskets we can get many many miles from an old ohv 4.0

View attachment 438711
View attachment 438712

Beige?

 

[fabianoliver]

Thanks 410 for your reply, and the time to take it.
I’ll do the homework.
I have here 2 pictures of the removed sparks
The sticker Frente means front of the car
can you discover any things looking them? Even if it’s not related to this leak
Thanks !!!

 

[fabianoliver]

With flashlight check over the engine area very carefully looking for any coolant leaks external. After all hoses and clamps are ruled out

The lower intake manifold, freeze plugs, head gaskets, timing cover, thermostat housing and water pump are all suspect

After
Visual inspection you can use a coolant system pressure tester to add pressure to radiator and help spot leaks. You can add a dye to the coolant and use a light to spot any leaks.

It is quite possible you have a seeping head gasket or lower intake gasket and the coolant is being burned up in the combustion chamber
In fact any 93-94 ohv engine that is still on the road needs to have its intake and head gaskets replaced, age and wear tear will have caused a failed gasket by now for sure!!!
A small leak now will likely continue to grow
Careful inspection of the spark plugs can identify which cylinders are burning water
If the previous owner used a head gasket sealer it can wear off every season and the leak will return, more
Sealant would be added and the cycle continues

If you do determine that the leak is internal and not external you may consider some gaskets and cooling parts as preventive maintenance
I often Re seal ohvs
I can get reman heads out if Texas for $550 a pair including the return labels to return the cores. Along w new
Bolts and all new engine gaskets we can get many many miles from an old ohv 4.0

View attachment 438711
View attachment 438712

My god! Nice!!!!

 

[410Fortune]

One or more of those plugs have white tips like the light brown and carbon (black) has been washed away by water

 

[fabianoliver]

One or more of those plugs have white tips like the light brown and carbon (black) has been washed away by water

These are bad news…..

 

[RowdyFitz]

I’m a little late to the conversation, 410Fortune is spot on with my process of elimination and my diagnosis upon seeing your spark plugs.
It is fairly common for these engines to crack or warp a head due to bad castings or over heating. I would also make sure to rule out a leaking intake manifold gasket before I say it is a head gasket or cracked head though.

 

[DaSovietPotato]

I would hope that it is a bad head gasket, as the only other answer would be a cracked/warped head.

 

[Turdle]

Hello all !!
My 94 xlt manual transmission 140K miles, consumes coolant since i bought it 4 months ago.
Now is summer here, and the other day i needed to refill the radiator and expansion tank with half gallon ( 1,7 lts) after 280 miles mixed driving.
The fuel tank cap seems in good shape ( not too old), and cames with the truck. I don't know the bar specs of it ..
I don't see coolant speeled in the floor, or in the engine compartment, and i've never noticed a vapor pressure coming from the engine.....
The engine is running fine, and the truck is in very good condition now.
When i changed the plugs, the old ones seemed fine, at least at my eyes.
What can be the cause?, and how can i test to try to figure it out?
The temp gauge is fonctioning ok, and the needle stays always just befor the "N" letter.
Any advice is welcome
Thanks!!!

If auto trans check fluid for cross contamination..

 

[410Fortune]

Don’t sweat it there are likely no 91-95 ohv I. The road anymore that do not need a complete re seal, the gaskets just get old and deteriorate
Good chance to look inside your engine and refresh all worn parts,
Clean injectors and re seal w new gaskets
Do it now and it costs very little wait and it gets more expensive

 

[fabianoliver]

Don’t sweat it there are likely no 91-95 ohv I. The road anymore that do not need a complete re seal, the gaskets just get old and deteriorate
Good chance to look inside your engine and refresh all worn parts,
Clean injectors and re seal w new gaskets
Do it now and it costs very little wait and it gets more expensive

Thanks all
In the tune up I’ve replaced the injectors ( the Mecanic done it, not me ) and they use new gaskets.
I’ll inspect meticulously the engine exterior, and start to think about regasket the head, and make a budget…
To buy a new head in USA and send mine is really expensive cause they are heavy “objects” shipping will be far more expensive than parts.
Recently for a 150$ motorcraft shocks I paid 300$ on shipment ( )

 

[fabianoliver]

If auto trans check fluid for cross contamination..

Hi Turdle, is Manual 5 speed

 

[410Fortune]

Inspect your heads and consider having them repaired at a local shop? Maybe cheaper

Pretty easy to spot issues w gaskets, valvetrain and heads when you take it all apart. Many threads here on where they crack and what to look for
I like to take things apart before I order parts when possible

 

[TheGourdGod]

I would bet my left nut that there's a crack between the valves on one of the cylinders.

 

[fabianoliver]

Inspect your heads and consider having them repaired at a local shop? Maybe cheaper

Pretty easy to spot issues w gaskets, valvetrain and heads when you take it all apart. Many threads here on where they crack and what to look for
I like to take things apart before I order parts when possible

Yes, seems cheaper to repair it, than to bring one from usa...let's see how it goes.

 

[fabianoliver]

I would bet my left nut that there's a crack between the valves on one of the cylinders.

"·$!!%$!

 

[ChildIdenticant]

I would bet my left nut

Why is it so often the left one that is wagered???

 

[Needmopower]

Hello all !!
My 94 xlt manual transmission 140K miles, consumes coolant since i bought it 4 months ago.
Now is summer here, and the other day i needed to refill the radiator and expansion tank with half gallon ( 1,7 lts) after 280 miles mixed driving.
The fuel tank cap seems in good shape ( not too old), and cames with the truck. I don't know the bar specs of it ..
I don't see coolant speeled in the floor, or in the engine compartment, and i've never noticed a vapor pressure coming from the engine.....
The engine is running fine, and the truck is in very good condition now.
When i changed the plugs, the old ones seemed fine, at least at my eyes.
What can be the cause?, and how can i test to try to figure it out?
The temp gauge is fonctioning ok, and the needle stays always just befor the "N" letter.
Any advice is welcome
Thanks!!!

I had a similar problem for years and it ended up being a hair line crack on the neck part of the radiator where you fill it. Never leaked or pooled anywhere apparently it would evaporate when it was hot.

 

[fabianoliver]

I had a similar problem for years and it ended up being a hair line crack on the neck part of the radiator where you fill it. Never leaked or pooled anywhere apparently it would evaporate when it was hot.

I hope it is a radiator or water pump problem, it is certain that if it were outside the engine block the leak would be somewhere that evaporates due to the temperature. Thanks for your comment