New member here, possible head gasket leak 01 expy

[nerdwrench87]

Because he doesn't care about the car, and just using it to get by until he can buy his girl a Camry. Man it just sucks, this ex has got lots of sentimental value to me, but I can't see any sense of dropping another 2+ grand into it ( that I don't even have!)

The world is a cruel place sometimes huh? Hah...

 

[nerdwrench87]

Have decided to do the work, mechanic here said he'd do it for a 30 pack, and I can get the heads machined for 80 a head. Pics will be coming.

 

[nerdwrench87]

Question. I've been thinking about it, and I know the 5.4L heads will bolt up and work fine on a 4.6L block, and give some more power and performance, but at what cost? Would it be safe to put 5.4 heads on a 4.6 block that has 150k on it? Or is that just begging for lower end trouble?

 

[nerdwrench87]

Update. I put the thermostat in wrong. Out it in correctly, and drove it to work as a test drive. No problems. Drove it to work this morning, and had the heater on, it overheated not even 15 minutes into the drive. Released pressure in the overflow, and all was well.

Left work tonight, didnt turn on the heater. No overheat.

Both previous times it overheated, the heater was on.

So seems like it only overheats with the heater on.

What's going on here? Any thoughts?

 

[stamp11127]

First clue is back in your original post. Upper hose is hot, lower is cold or luke warm. Partially clogged radiator from running improper coolant mix. All the crud in the system has clogged most of the passages. The water pump pulls the coolant in from the lower hose. If I remember correctly, on the diesel engines back at the shop, we have about a 15 degree difference in temp from inlet to outlet at operating temp.

For cleaning the cooling system we don't bother with all the "fancy cleaners". We use either Dawn or Cascade liquid and let it run for a while once the engines are up to temp. Does a good job, used it at home on some of the projects.

 

[nerdwrench87]

So just drain the radiator, fill it with tap water, mix in a bottle of dawn, and run it?

 

[stamp11127]

Before doing anything I would remove the thermostat, remove the upper radiator hose from the radiator. Using a garden hose, while filling the open end of the upper radiator hose with water, watch the amount of water and clarity that comes out where you disconnected it. If there is good flow coming out, should be equal to what is going in, then the radiator is probably fine. If not I would add some Dawn or Cascade and let it run - connect the hose back of course. After about 15 mins at operating temp, let it cool and drain the system. Repeat the above steps and see if the flow has increased. If not, new radiator time. Remember to install the t-stat when finished.
If you go to a new radiator, get the 2 core instead of the single core. Change the lower hose, dump that quick connect nonsense connection at the lower hose and use hose clamps. With all the crap that was in your system, you'll pay hell getting the hose off. I just cut mine and replaced with new.

 

[nerdwrench87]

Before doing anything I would remove the thermostat, remove the upper radiator hose from the radiator. Using a garden hose, while filling the open end of the upper radiator hose with water, watch the amount of water and clarity that comes out where you disconnected it. If there is good flow coming out, should be equal to what is going in, then the radiator is probably fine. If not I would add some Dawn or Cascade and let it run - connect the hose back of course. After about 15 mins at operating temp, let it cool and drain the system. Repeat the above steps and see if the flow has increased. If not, new radiator time. Remember to install the t-stat when finished.
If you go to a new radiator, get the 2 core instead of the single core. Change the lower hose, dump that quick connect nonsense connection at the lower hose and use hose clamps. With all the crap that was in your system, you'll pay hell getting the hose off. I just cut mine and replaced with new.

Sounds like a typical flush. Ill try it. Thanks! I'm just praying that the small bubbles that occasionally appear in the overflow tank is just excess air in the system. ...and I'm hoping that the tech at work was right, that a standard "block test" kit which uses a vial and bulb to sample the air in the radiator, is it very accurate on cars with a sealed radiator, because the truck runs beautifully. Needs a tune up from sitting for 2 years, you can feel a slight shudder occasionally, but other than that, yeah.

If it is a HG... I'm in for some work. Ill repost back soon when I get a chance to do the flush.

 

[stamp11127]

Haven't had to use the test kits. Usually when the head gaskets let go on the mechanic specials I get, they tend to puke all the coolant out of the tank when warm. Also they will blown white steam out of the tailpipe - dead give away.

When cold they will pressurize the cooling system right after the engine has been started, and you'll get a noticeable amount of air leaving the radiator when removing the cap. More than what you would expect from coolant that hasn't had time to expand from heating.

And the other worst case is when its obvious that your oil level has risen or your coolant is suddenly turning milky brown in color.

 

[nerdwrench87]

None of those things. Idling for a few minutes the hoses don't get pressurized. My old Toyota blew its cookies at 600,000 and I had the misfire and when I drove it to the shop, I made the entire neighborhood look like the great American smoke out. Thankfully getting none of that.