4.0 SOHC head gaskets/timing chains

[Uncle Gump]

Those plastic lines get brittle over time and all the heat cycles.

It's good to inspect the full length...

 

[JJMaine]

Looked over everything and it's all connected correctly and can't find any breaks or cracks though it's hard to look under that casing. There was that end that broke off but it's reconnected great with a zip tie around the rubber holding it in. Tried my hardest to pull it back out but couldn't so I'm sure it's sealing.

Is there a way to test things to find the leak or could the heater control valve be stuck from sitting or something? Not terrible concerned about it as the truck stays on defrost 100% of the time during winter.

 

[JJMaine]

Oh and the truck definitely has a little more poke now that it doesn't have a head gasket issue. Though I robbed that power back today by putting my heavy winter tires on and 5 bags of pea gravel in the bed

 

[Uncle Gump]

You made sure you have vacuum at the ball?

I think if you roll down the glove box you can get in there a bit to see and or test a bit.

 

[JJMaine]

No I didn't I just checked everything over visually and quickly. I'll check out behind the glovebox and check the manual for any tips as well.

 

[JJMaine]

Truck seems to be idling a bit higher than before around 900rpm. Im just going to drive it and see if it settles down a bit since it's been running rough ever since I've owned it. Probably doesn't know what to do with good compression in all cylinders now

 

[Uncle Gump]

Or... you have a vacuum leak in the line that feeds your HVAC controls??

 

[JJMaine]

Oh thatll do it? It's all making perfect sense to me now. Now I'm going to have to hunt the leak down. The manual has 0 info on the HVAC vacuum system or how to test that I could find. I'd just replace all of the vacuum lines if I could find them for sale.

 

[JJMaine]

Would the brake cleaner method work to find the leak then since it's affecting idle?

 

[Uncle Gump]

I prefer using propane...

 

[JJMaine]

Awesome I've got that too. I'll see what I can find.

 

[JJMaine]

So I found the culprit. It is the vacuum lines that come from the intake manifold to the PCV, EGR and fender ball. Propane didn't get me any results but I can hear a slight hissing and when I pull on the lines up by where they plug into the intake the hissing stops momentarily.

Does anyone have a spare set of these vacuum lines by chance? What's my best bet, find someone that's parting out a Ranger and get the lines off it? I'm sure Ford doesn't sell these new anymore...

 

[Shran]

Usually with those you can pull the rubber end off, shorten the plastic hose past where it's cracked and shove the hose back into the rubber piece.

 

[JJMaine]

Ok nice I'll give that a try if need be. I wish I had inspected that good before putting it back on because it sat in my shop for months lol.

 

[JJMaine]

So found the culprit. The line vacuum line that goes to the fender ball is broken in many many pieces. I got the part number off this set of lines and they are still available. Is it fine to cap this line off and run without the heat selection for now while I get a new set of lines? The ones going to the EGR and PCV appear to be fine.