The Problem:

My head gasket seems to have sprung an external leak right under my thermostat.  I've got a big trip coming up next month with a pregnant wife, a 4 year old, and a 7k trailer on mountain roads, so I've got to get this squared up, and done correctly (though not overkill).  I'm very capable with a wrench, and have been through every facet of gassers over the last 20 years, so I'm not worried too much about tackling it (other than the 200lb weight of the head).

 

As I move forward I have a couple of planning questions to ask.

 

What tools will I need other than the basics (I've got a decently stocked roll away with the basics)? 

I don't mind spending up to 50 dollars for a job, or engine, specific tool that I'll someday need again that will make the job appreciably easier, but I don't mind making do to save some cash either.  I have a barring tool, but that's the limit of my Cummins specific stuff.  Should I get an injector puller?  Anything else?

 

What gaskets will I need?

I'm planning on buying Genuine Cummins (have a local dealer).  I figure I'll need a full top end set (PN 4090035), are there any additional gaskets or parts that I'll need other than head fasteners (see next question)?  Injector seals?  Anything?

 

Bolts or Studs?

I know studs aren't truly needed unless I'm pushing higher boost numbers than I'm likely to ever hit, but I don't mind springing for it if there is an appreciable level of genuine peace of mind to be had from it.  I hear that bolts can be reused, and often are, but there seems to be a lot of voices saying not to, which is pushing me to at least replace the bolts (approx $120 for a set).  I would really be bummed to shell out for that, when a new set of studs is not a whole lot more ($405 for ARP 425 series).

 

Tips?

I've got an alldata subscription which will give me most of the steps that I need, but I welcome any tips, shortcuts or encouragement you can offer. 

 

Other things of note:

- Currently my oil is not milky, and I can't see any evidence of oil in my coolant, so I think my leak is external only.

 

- I won't start this job until the end of next week.

 

- Once off, I AM planning to get the head surfaced, and checked for cracks... Is there anything else I should have them do?

 

- To do this job carefully, and on the slow side, what should I ballpark for time spent on actual work (not waiting for machining, etc)?

 

- My truck is my daily driver.  I don't ever plan on making it a beast.  At this point I'm happy with it's current power output, and really only could imagine going up to 400 hp on the outside. 

 

- I'm the sort of person who wants to do things the right way, the first time.  I don't go overkill nuts, but I also don't need to skimp to save $20 that I may regret later. 

 

All help is appreciated

Edited June 11, 20159 yr by Nates1999

Are the 24V gaskets not MLS?

 

Do you think it is combustion pressure pushing on the coolant?

 

Not sure about MLS.

 

Yes I think I have combustion pressure in the coolant.

Sounds like the cap to me. If there is anything over 12 or 14psi I can't remember which our cap is, it should pour into the overflow not out any of the boots. Where did you purchase your cap from?

As for clamps you need the constant tension spring clamps. It'll keep those hoses tight through the expansion and contraction.

You really need to test and see if you are getting pressure into the coolant system with a gauge. If the pressures are that high it could blow out freeze plugs and that's another story.

I believe our caps are set at 16psi.  I replaced my old leaking cap with a factory dodge cap (which still leaked a little), and then a NAPA cap, which didn't leak at all before I changed the gasket.

 

I never had any coolant seepage at the hoses before the gasket

 

Hoses are rock hard most of the time now. Problem seems most noticeable right after cold startup.  I think it seals itself up when it gets to temp.

What happens when you start it cold with the cap off?

Well.  I put on a new cap (again) and new clamps (used constant torque types) and it appears that the issue is gone... Yay!  Clamps I was originally sold were way too big for the hoses.  They "wormed" down nice and tight, but the new ones are MUCH higher quality.  Hopefully all good now.