Just checking out my motor with the intake off and on the passenger side head below the #4 intake port, theres a threaded bolt hole with no bolt in it and looks like oil is on the threads coming out of it when the motor is running but im not sure... Anyone know what this is for and why its empty or is it supposed to be? My block down in the V is covered in sludge/grease and im thinking this might be the problem? Dunno though... 01 5.4.... Thanks

 

On modular engines the cyl heads are cast the same and machined (basicly)the same but are reversed for opposing sides of the engine. So the rear of the passengerside cyl head is what will be at the front of the driverside head. I believe what you are seeing is a bolt hole that is needed at the front driverside for the intake manifold. You should also be able to see part of the intake gasket at the passengerside rear. Not sure how oil can migrate through that bolt hole to the outside even if there was porosity. I think you have an oil leak somewhere else and its just filling that hole and also possibly getting into the engine valley.

 

Thanks for the reply.I havent checked on the drivers side head if there is a hole in the front or not but, the hole is sitting at an angle in the back passenger side and all the intake bolts go in straight up vertically. Ill try to get a picture of it tomorrow for you.

 

Is it in the valley portion of the cyl head and larger than the intake bolt holes? If so I'm thinking it may be the CHT (cyl head temp sender) hole which is on both heads but only the driverside has the sending unit and its at the front. If thats what it is and oil is coming out of it then you very well may have porosity in that head. A picture would help a lot. Take care.

 

Yea, a pic will help. I dont have my cam with me right now but ill get one tomorrow...It is in the valley portion of the head but not on the block, on the head itself and yes the hole is larger than the intake bolts. Is the CHT on the front driver side head below the t-stat? Im not sure if oil is coming out of the passenger one or not...the threads just have a bit of oil on them and the valley is caked with sludge/oil.Is why you're saying the head might have porosity because the holes bottom out at some point? Thanks again.

 

I think I had the same concern as you when I purchased a used motor and noticed this...

This is the back side of the passenger head, where you can see the intake manifold gasket and an empty hole.



Then there is also this, where the CHT sensor I believe was casted on the passenger head but not used.



But as dynotech said, no concern, as they are casted the same but not used on the passenger side. They go to nothing, and there shouldnt be any oil in them. But if you have sludge in the valley, some may be in there as well

 

Yep. The 2nd pic hole on the passenger side is the hole.... Thanks a bunch...It threw me off because it looks like something worked its way out of it....

 

Yeah, I thought the same. That's why I had the arrows and question mark. I thought there would be at least a plug, but was told nothing goes there.

 

Cool. Thanks both you guys. Appreciate the help.

 

Yep thats the unused CHT hole. Remember because the heads are cast and machined the same that hole gets threaded as well even though there is only one CHT sensor and it is installed in the front of the driverside head, same hole only heads are reversed. They are blind holes so no plug is used/needed in the rear unused one. I doubt there is any oil coming out of that rightside hole though unless you have serious porosity. The cyl heads are all machined the same and sent to the cyl head assembly where they are orientated either rightside or leftside heads, once the cams are set in them thats basicly what dictates which side head they will be. Thanks Toyz for the pics helped a lot.

 

Not all heads have the CHT port, may be a truck thing.....had to drill my own, FRPP heads. I'm not sure how the pic got so small??