54' 331 Hemi

[SugarRay8]

On my Hemi I can feel air coming out of the spark plug tubes. Seems like the plugs aren’t sealing into the head, but they are tight. Any ideas what I need to do, maybe the tubes themselves are not seating properly?

 

[SugarRay8]

Well, guess nobody had any ideas.
We took the valve covers off and it looked like the oil wasn’t getting through all the rocker assembly like it should. We took the rocker assemblies off and soaked them in diesel fuel for two days, blew them out with compressed air and everything looked like it was flowing properly. We reassembled everything and cleaned, “dressed” the plug tubes and reseated them. We also checked the timing, made sure it was where we needed it. The engine fired right up and idled great, also it has no air or smoke coming out of the plug tubes.

 

[42chevy]

That is a weird one! I have NO hemi experience so good job.

 

[SugarRay8]

Thanks, it's my first time messing with one and I'm wishing I had picked one up years ago. It looks intimidating at first, but it's a really simple motor to work on, at least what I've done with it so far.

 

[Gastrick]

SR8, When you cleaned out the rocker shafts, did you remove the caps from the ends to do it. It's the only way to really clean them out well. Good job as this is is a common issue when not addressed and if not caught in time can of course lead to some real damage. Also, the spark plug tubes are considered an expendable items that get replaced when they start getting marred. One last note, if your spark plugs came with the aluminum gaskets at the thread base, they NEED to be romoved before installation into a hemi. Some people get them to seal, but it's not correct and can lead to leaks and damage your spark plug tubes. I'm not trying to insult your hemi knowledge, I'm just tossing these things out there in case you didn't know.

 

[SugarRay8]

SR8, When you cleaned out the rocker shafts, did you remove the caps from the ends to do it. It's the only way to really clean them out well. Good job as this is is a common issue when not addressed and if not caught in time can of course lead to some real damage. Also, the spark plug tubes are considered an expendable items that get replaced when they start getting marred. One last note, if your spark plugs came with the aluminum gaskets at the thread base, they NEED to be romoved before installation into a hemi. Some people get them to seal, but it's not correct and can lead to leaks and damage your spark plug tubes. I'm not trying to insult your hemi knowledge, I'm just tossing these things out there in case you didn't know.

Thank you!
We did not remove the caps, so I’ll re-clean them with the caps off.
Also I’ll remove the aluminum gaskets, we’ve only ran the motor about 5 minutes total, so it should still be fine.
As for my Hemi knowledge, I have NONE, so please keep tossing out all you can.

 

[biggeorge]

Hot heads is a great place for Hemi's they have a forum and some really smart people lurking around

 

[Gastrick]

Thank you!
We did not remove the caps, so I’ll re-clean them with the caps off.

The caps are similar to a freeze/core plug. They will need to be replaced if you remove them. I will add that the inside of those shafts should be really clean and free of obstruction as the lubrication to the valvetrain components travels through them.

 

[SugarRay8]

The caps are similar to a freeze/core plug. They will need to be replaced if you remove them. I will add that the inside of those shafts should be really clean and free of obstruction as the lubrication to the valvetrain components travels through them.

OK, I’ll make sure I have some new ones before I take these out.
We did run it, and everything is getting oil right now. I just worry about some loose debris floating around and eventually plugging something off.
Thanks again for the advice/help.