OK guys I need some help here.

BAD NEWS.....

I'm getting coolant into the left bank cylinders. My first thoughts are either blown head gasket or cracked head? These are the older EQ heads that were supposed to cure the cracking issues so I'm really hoping it's not the head. So we know I've been having sealing issues with this 6 pack intake but is there a way that I could be getting coolant into the cylinders by the intake?
I'm going to start taking the engine apart tomorrow and figure I'll pull the intake back off and then take my exhaust off before I do anything else. Just looking for ideas or suggestions on other things I can do or check before I rip things apart too far. I really think for ease of getting to the cylinders I should get the headers out of the way. Then I could do a compression test or lead down test if needed.
This doesn't happen until the engine has ran long enough to start getting warm. It's almost like the issues I'd had with my old engine. Once it's warmed up it's pressurizing the cooling system where it's blowing coolant out the overflow reservoir.

 

I'm wondering about the intake. In one of the photos I saw was a MOPAR part number. It appears that the intake is a standard small block MOPAR six pack intake that has been modified for fuel injection and the magnum intake bolt pattern. I'm wondering if there is a possible crack somewhere in the intake allowing coolant to seep into your cylinders? Might be easy to have a machine shop check that 1st before tearing the motor apart.

 

Which cylinders do you suspect? 1, 2, 7, and 8 would be possibly close enough to the crossovers, But I find that unlikely in the extreme. (intake gaskets) Possible crack between intake runners, and coolant passages is indeed a possibility, but again, only on the 4 mentioned cylinders. Cracked heads, or bad head gaskets are also possible.

 

Yes it was the 6 pack intake that Mopar use to sell and then F&B modified it to allow fuel injection & fit the magnum engines. I don't know how it could be allowing coolant into the cylinders but it sure seems suspect.

I'm about ready to just say "F" it and get an Air Gap and then either a 4 barrel TB or UTA's TB.

 

Maybe pull the intake (again......) bolts some plates to it with gaskets on the mating surfaces, then pressurize 'em, see if they hold pressure, or it bleeds off.

Do you know which cylinders are getting coolant??

 

I'd have to check again but I think 1, 3 & 5. I'll have to pull the plugs again and check.

I guess my question is could I have damaged the engine with it getting so hot when it was running lean? This problem started after the second time I'd installed the intake. When it had done this after that last time I'd installed the intake I'd thought (hoped) that it was due to the manifold not sealing well enough. I'd blown out the cylinders and once I had reinstalled the radiator and filled it I pressure tested it to see what would happen. It held pressure so next I cranked it over to see if it built up more pressure which it didn't. So I thought (hoped) it was OK. I let it run for about 4-5 minutes and the water temp was up around 180* on the gauge. Shut it off and next thing I know it's blowing coolant out of the overflow reservoir again.

The intake doesn't have a water crossover in the rear only in the front. Which I'm not sure if this could cause issues or not?

 

Is it a common plenum between all 8 cylinders?

That sounds more like a headgasket problem to me.... but, testing the intake to see if you aren't getting coolant into the runners still is a good idea.

 

Yes it's a common plenum between all 8 cylinders.

I really think it's a head gasket also. Just not sure How or Why but I guess better now than later. I ordered Cometic head gaskets for it this time. And I'm assuming I should do both head gaskets?

 

Hearing what you went through with the engine running sounds more like a head/head gasket issue. Sounds like the top half of the motor will need to come apart to check things, not necessarily the short block.

 

I would do both, just because I am a bit OCD when it comes to that sort of thing......