Small Leak From Head After Re-surfaced

[ARZ 5.0]

Just got motor back in the fox, was driving yesterday and after I parked it I noticed a small puddle under the car. Found a very small leak coming from front corner of the head. Only leaks after car cools off. I was going to recheck torque first but was just wondering if anyone has had this issue. Really don't want to pull heads again but wanted to hear opinions.

 

[7991LXnSHO]

Seems like someone just had a bolt that went into the coolant jacket leaking. If that is not it, you are looking a gasket. Time for some leak dye and a black light to trace the leak before it fills up the oil pan or a cylinder.

 

[tonydalrymple]

When you say "corner of the head"; do you mean the very outside corner or where the head meets the intake? If the latter; odds are good the intake is not sealing well... Not unusual when the heads are milled & the intake isn't IMHO.....

 

[ARZ 5.0]

When you say "corner of the head"; do you mean the very outside corner or where the head meets the intake? If the latter; odds are good the intake is not sealing well... Not unusual when the heads are milled & the intake isn't IMHO.....

I mean the very outside corner. Where the head meets the block. I'm wondering if the gaskets will set as they heat up with time or should I just plan on taking it apart again.

 

[ARZ 5.0]

I mean the very outside corner. Where the head meets the block. I'm wondering if the gaskets will set as they heat up with time or should I just plan on taking it apart again.

What is IMHO?

 

[Killa]

I think it In my Honest Opinion ( research say when ever some one say In my honest opinion, they really mean that not what they really think .)

 

[89oem]

imo - in my opinion - i believe this

imho = in my humble opinion - i believe this to be true but others may have a different opinion

iirc = if i recall correctly

 

[madspeed]

Edited

 

[rbohm]

ok you see the leak as being at the lower front corner of the head, but i believe that the leak is where the intake meets the head. why? because you had the head milled, but you probably did not have the intake also milled, and as such you have changed the relationship between the intake and the head.

most of the time when the amount taken off the head is small, there is enough "tolerance" that there is no issue. however production tolerances being what they are, and with tolerance stack being what it is, there is the possibility that you ran out of tolerance and now have a small leak. it wont get better over time just worse.

what you need to do now is measure how far off the manifold is from the head, and determine how much the intake needs to be milled to bring things back into tolerance.

 

[madspeed]

Did you use rtv around the coolant ports when putting on the lower intake?

 

[89oem]

ok you see the leak as being at the lower front corner of the head, but i believe that the leak is where the intake meets the head. why? because you had the head milled, but you probably did not have the intake also milled, and as such you have changed the relationship between the intake and the head.

most of the time when the amount taken off the head is small, there is enough "tolerance" that there is no issue. however production tolerances being what they are, and with tolerance stack being what it is, there is the possibility that you ran out of tolerance and now have a small leak. it wont get better over time just worse.

what you need to do now is measure how far off the manifold is from the head, and determine how much the intake needs to be milled to bring things back into tolerance.

perfect example of either imo or imho either way you should check this scenario... makes allot of sense...

 

[madspeed]

perfect example of either imo or imho either way you should check this scenario... makes allot of sense...

Iirc, you used all the **** we talked about in one thread

 

[jAEded]

Did you use any thread sealer or anti-seize on the exhaust side head bolts? The threaded holes in the block are open to the cooling system.

When I first did my heads, my car had leaks from the same spots. At the time my car was running so lean that it was taxing the cooling system. New gaskets and taking off everything that was leaning it way out helped a lot. In my circumstance any ways.

 

[rbohm]

Iirc, you used all the **** we talked about in one thread

he is quite talented that way isnt he? me thinks he might be a keeper.

 

[ARZ 5.0]

Did you use rtv around the coolant ports when putting on the lower intake?

Unfortunately I was not there for the whole install as the car was in ATX and I was in Houston so I'm going to ask the shop that did it. I just drove about 50 miles and it ran very good but got a little hot at the end. Need to get a tune ASAP.

 

[ARZ 5.0]

ok you see the leak as being at the lower front corner of the head, but i believe that the leak is where the intake meets the head. why? because you had the head milled, but you probably did not have the intake also milled, and as such you have changed the relationship between the intake and the head.

most of the time when the amount taken off the head is small, there is enough "tolerance" that there is no issue. however production tolerances being what they are, and with tolerance stack being what it is, there is the possibility that you ran out of tolerance and now have a small leak. it wont get better over time just worse.

what you need to do now is measure how far off the manifold is from the head, and determine how much the intake needs to be milled to bring things back into tolerance.

Ok thanks for the help I'm going to look into it.

 

[rbohm]

Ok thanks for the help I'm going to look into it.

what you want to do is clean off the old gasket material, and set the old gasket in place and set the manifold down as it would sit on the engine. no seaaler, no end gaskets no bolts, etc. and see how large of a gap you have between the intake and the block. you should also remove any plugs or sensors above the coolant port in the intake where it meets the head, and see if you can tell if the openings still line up reasonably well. its possible that you just need to do a better job of installing the intake, especially is you used the cork or rubber end gaskets instead of a bead of silicon.