383 water coming from valve cover bolt

[Matt DeCicco]

I have a 383 with aluminium heads. The motor was recently done and running good. I was on the highway and the car started to smoke and burn oil so I pulled off and noticed the pcv hose fell off. I re attached the hose but the car was still running funny.. I just loosened a valve cover bolt and water started coming out on the passenger side rear lower hole. Is this a head gasket? I have had the covers off before and didn't have this problem. Thanks for the help

 

[oldbee]

Sounds like your bolt is in the water jacket(?), never heard of this; but no experience with alum heads.

 

[mopar 3 B]

Start checking for head casting cracks. Take the head off and have it magnifluxed.

 

[69Bee]

Dye penetrant for aluminum, magnaflux for cast iron, same check, different method. It is unlikely you will see anything though. It might just be the hole goes to water, and it normally has a stud in it which is not removed when you R&R the valve cover.

 

[5.7 hemi]

What aluminum heads are these? This is awfully strange.

 

[Matt DeCicco]

They are promax heads. I'm going to call in the morning to see if they can give me any insight. I stuck a piece of wire in the hole, and it seems like it does not bottom out like the other holes. It's strange that it didn't do it before, I'm hoping the hole just got drilled and tapped a little too far and it took time, but after having a bolt in and out a few times it finally started to leak. If that's the case I'll just use sealer on the bolt.

 

[HT413]

They are promax heads. I'm going to call in the morning to see if they can give me any insight. I stuck a piece of wire in the hole, and it seems like it does not bottom out like the other holes. It's strange that it didn't do it before, I'm hoping the hole just got drilled and tapped a little too far and it took time, but after having a bolt in and out a few times it finally started to leak. If that's the case I'll just use sealer on the bolt.

No experience with those heads, but if they say this is normal, do yourself a favor and stick a stud in that hole with some Permatex. That way you can remove the valve covers without reopening that water jacket.

 

[Larrywre]

What about the car running funny and smoking! A pcv hose off would not do that, may be a larger problem than water coming from a bolt hole.

 

[HT413]

Is this a head gasket? I have had the covers off before and didn't have this problem

Just rereading your post - like a dope, i missed this part. I can’t see how coolant can come out of a valve cover bolt hole unless that head is cracked. Even a head gasket doesn’t make sense.

 

[Matt DeCicco]

Initially I thought that was due to a bad alternator. The voltage was spiking up randomly, I changed it along with the voltage regulator

Just rereading your post - like a dope, i missed this part. I can’t see how coolant can come out of a valve cover bolt hole unless that head is cracked. Even a head gasket doesn’t make sense.

That's what I wasn't sure of.. I'm not too familiar with how the water passages layout. I'm sending in a picture to promax so they can come up with what they think it could be

 

[The Shoe]

Story for being late to the game here, and I'm not sure if you've figured out you cyl head troubles. The lower end valve cover bolts on stock heads do have the water jacket behind the threads, but the casting is not open to the threads. Sounds the your aluminum heads are cast the same, and have broken thru into the water behind that bolt. I had a customers 440 that did the same, I removed the valve cover bolt on the lower front driver side and water began pouring out. Somehow, someone in the past had used a bolt that was too long and punched thru into the water jacket. The casting must have been paper thin in that area. I had to run a short Allen head bolt, covered in epoxy, into the hole to the bottom of the threads, then use a shorter valve cover bolt to stop the leak.

 

[moper]

Sounds more like porosity or a casting flaw, or the hole was drilled a hair too far. I'd use a stud with some liquid Teflon sealer and call it a day.

 

[Sjd556]

was just about to order promaxx heads for my 383 too, now that may change...

 

[Matt DeCicco]

Promax confirmed it is a bolt hole that is just a little too far. I have installed studs and sealed the one that was in water jacket, problem solved.

 

[5.7 hemi]

Outstanding!

 

[Matt DeCicco]

I should mention that it didn't do it out of the box, and the valve cover bolt was too long.. it must have taken 6 or so times before it finally broke through. Other than that the heads have been great, they even installed 10° locks and retainers for me.