Time for my first Cummins Headgasket

[Mopar1973Man]

You have to remember the coolant pressure on the head gasket is about 40 PSI. I've found it about a year ago where a member on CF hooked up a pressure gauge and showed the pressures at the head. It varied of course but the max pressure I remember seeing is 35-40 PSI. This is pressure created by the water pump.

[Wild and Free]

 wow, when i rebuild my tractors eng. [john deere]     i also reused the head bolts & thats where the 'fun' began,  i had some stretch [wouldnt torque to ft. #] but the 1st one that did this just wouldnt get tite so i just kept turning.  .......& then SNAP!!         NOW WHAT!!!!               thank fully i was able to just back it out w/ a sharp chisel........whewww! 

 

point of lesson, dont just use them....check them 1st!  and if they dont get tight, stop!    

When was the last time your torque wrench was calibrated? Never ever trust a torque wrench unless it is calibrated at least once a year at minimum even a brand new one should be sent in to be checked and tuned before use, especially the cheap ones. I have seen many stripped out head bolt holes in blocks and twisted off fasteners due to torque wrench calibration being off or the wrench just plain being bad period.

People miss this stuff a lot, we send in every torque wrench in the shop every year and pretty much every shop I have worked at have done the same thing, components are too expensive to take chances on due to mismanaged tooling.

[organicfarmer]

good point, w&f. yeah, i bought the cheap one! i used it prob. 5 times in the last 2 yrs.......[not another eng. though]

[Wild and Free]

Buying a cheap torque wrench to do detailed engine work is like buying a yard stick to set valve lash.

[Buzzinhalfdozen]

Buying a cheap torque wrench to do detailed engine work is like buying a yard stick to set valve lash.

Well since we're on this subject do you have a favorite brand? I've given enough of my money to the tool trucks over the years so I'd prefer to stay away from them.(snap-on,Mac,Matco) I've been happy with my stuff from Klein and Wright but they definitely don't give that stuff away.

[organicfarmer]

Buying a cheap torque wrench to do detailed engine work is like buying a yard stick to set valve lash.

     

[Wild and Free]

I personally prefer Snapon for torque wrenches, I have 5 of them, from 3/4 to a small inch lb break away screw driver style for very detailed tqs I used to do on the over the road cummins injector timing sets and adjusting jakes and valves too.

I like the quick set of the snapon versus the twist up handle. Plus if while in for calibration th higher quality brand name wrenches have better parts availability and can be calibrated easier as well. A lot of the cheaper ones are just throw away if they need internal work or don't meet calibration standards.

I use these guys locally.

[CUMMINSDIESELPWR]

a lil tip, when removing the pushrods, there are a couple plastic plugs under the cab lip that you remove to lift the pushrods up and into then pull them out. they need to come out for the head to remove.

[Nates1999]

I would seriously add some GM seal tabs and just do a re-torque for starters, that is not a bad leak yet. If it keeps leaking after the trial then jump to a new gasket. Ten bucks or so for the tabs and about an hour for the retorque is still a better bet to start with than jumping into a head job. Like I said prior my 02 did this at around 50K miles and I did the tabs and retorque and it never leaked again.

Those seal tabs are awesome, I have even seen GM Good wrench reman engines with them in from the rebuild facility. At the truck shop we actually put them in any time we did any engine work or coolant system work.

I defer to your experience.  It would normally not be my way of doing things, but I'm definitely giving it some consideration. 

 

I think I've got a couple of shops that I trust will give me an honest assessment, and not do more work than the head needs if I take it in, and given that I've already got the gasket kit (got the whole top end kit for a big discount from my local cummins shop), I think ultimately I will likely go ahead and do the job, just to know it's done and done... We'll see.  I suppose if it needs more machining than just a surfacing, than it's probably better that it gets done anyway. 

[Nates1999]

I personally prefer Snapon for torque wrenches, I have 5 of them, from 3/4 to a small inch lb break away screw driver style for very detailed tqs I used to do on the over the road cummins injector timing sets and adjusting jakes and valves too.

I like the quick set of the snapon versus the twist up handle. Plus if while in for calibration th higher quality brand name wrenches have better parts availability and can be calibrated easier as well. A lot of the cheaper ones are just throw away if they need internal work or don't meet calibration standards.

I use these guys locally.

Turns out I've got a calibration shop locally too.  I'll finally be able to get my 3/8" Matco wrench that my buddy gave me up to snuff.  I think I'm going to get a Precision Instruments wrench (who used to make Snap on's) for my 1/2" work, as I'm tired of my cheapie.  Looks like about $135 and they are good if not outstanding quality.

 

http://www.tooldiscounter.com/ItemDisplay.cfm?lookup=PREC3FR250F&source=froogle&kw=PREC3FR250F&gclid=Cj0KEQjwqe-rBRCv_J6qs6isp6EBEiQAmbctFltGQiqvZzN5rc248djnrHyWX_arYSVyJlm7MhJ8XncaAj2X8P8HAQ

[CTcummins24V]

I've been using CDI (made by snap on) for the past 2 years. Can't complain. Haven't over tightened/stripped/snapped a bolt yet. The collar gets moved too easily when wrenching but that's about it. All 3 I have cost $100-$140 a piece.  

[Nates1999]

Could anyone tell me...

 

Is it appreciably easier to do the Injection pump or the front seal when doing the headgasket.  I'm not that excited to add more to the pile, but if it's a lot easier I might try to do more stuff at once.

 

Injection Pump - Not cared for by previous owner, who allowed the factory lift pump to wear out to the point that when I changed the fuel filter, it wasn't strong enough to even pull prime (didn't have FP gauge at that time).  I've since put on a Fuel Boss, which is doing great, but still managed to throw a P0216 a few weeks back pulling up a pretty good grade.  The lift pump history or the code on their own wouldn't scare me so much, but both.... well I'm thinking it's probably time. 

 

Front seal - Not actually sure which seal it is, but I'm definitely leaking a little oil out the front of the motor, which leaks down with regularity.  Probably crank or timing case.

 

Thanks

[Wild and Free]

Injection pump would be a lot easier as you have most of it unhooked already pulling the head and everything above it is out of the way already, the front crank seal and timing cover really isn't affected by the head but still would be a little easier access as well not having as much stuff around above it.

[TFaoro]

If it's the timing case you've got a whole new world of work about to start. Whole front of the motor has to come off and the cam has to come out.

[Nates1999]

If it's the timing case you've got a whole new world of work about to start. Whole front of the motor has to come off and the cam has to come out.

 

............ err, forget the leak.  Why the heck would the cam need to come out?

[AH64ID]

The cam gear blocks the timing case. 

[TFaoro]

The cam gear blocks the timing case. 

And the cam gear is pressed onto the cam

 

You can replace the front main seal and reseal the cover if you like.

[Nates1999]

TFaoro (or anyone) ,you mentioned removing the insulation from the firewall. Do you mean remove as in rip it all out, or is there a way to carefully remove it so it can be reinstalled after finishing the job? Is it going to affect cab Temps and noise if it's gone?

Edited June 20, 2015 by Nates1999

[rburks]

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

  For pulling the CROSSOVER TUBES OUT , i would use one of the injector lines, you will probably have to remove at least a couple anyway,  i use an old injector line a had to replace yrs ago.     I'm not a fan of using pliers on them, it can be done but its 50-50 chance of marring one

and sometimes you'll not see it with the naked eye till it's squirting fuel everywhere and you can't stop it from leaking.

 

Here's a tip For Removing the INJECTORS : take a bolt from Intake horn/heater grids and a deep well socket thats big enough in diameter to fit over injector and the injector bore.  place socket over bore/injector and place a large flat washer on top of socket. now place bolt thru socket and thread into injector and tighten...injector will pull free from bore in head..

P/S "you may have to use a big hex nut for spacer if needed "

 

I have photos of doing this somewhere, ill see if i can find them

Edited June 20, 2015 by rburks

[Nates1999]

I bit the bullet and ordered an injector puller and crossover tube puller. They should be here today.