Engine/Transmission (1998.5 - 2002) Blew Intake Manifold Gasket

[rubberneck]

Well, turned Powermax on tonight for the first time in a while racing a buddy home from work tonight in his PSD. Noticed boost was down about 6 psi and temps were up about 100 degrees or so from normal numbers. Figured intercooler boot had worked its way loose no big deal. Well all clamps were tight and no signs of slippage on any of them. After further investigation noticed gasket between air horn and intake heater bulging out toward valve cover. Figured no big deal 5 minute job to replace it in the morning. Then i looked down and noticed the gasket between the aluminum intake manifold and head bulging out on both sides Now it just turned in to a 2 hour job and all the high pressure lines have to come off to get to it. Guess the daily trips up to 50 psi boost finally took their toll on the poor thing. Oh well. Any body know the part number for just the intake manifold gasket. I have spares of the square gaskets that go between the air horn and heater, but I guess i'll have to order the intake gasket.

 

[tgbol]

I only have the Cummins Numbers

Gasket, Intake Manifold Cover 3931347

Cover, Intake Manifold (Just in case) 3941437

Gasket, Connection (Heater Plate) 3931604

Have Fun

 

[Alan Reagan]

I don't know if you had ever torqued the intake bolts to spec before this happened but I have yet to check these bolts and not have to tightened them up to 2 full turns before they reach the specified torque. Running high boost will certainly blow out the gasket if the intake is not torqued properly.

 

[Bandit1]

what should they be torqued to, i would rather check the bolts and prevent this from happening,

 

[Bob Wagner]

2 step procedure

1st step. tighten all bolts to 24 inch lbs



2nd step tighten all bolts to 84 inch lbs



done

 

[HVAC]

Rubberman

It's not so uncommon Rubber, happened to Chris too. I have replaced that cover without pulling the high pressure lines off. Everybody should go over those bolts and check them.

 

[rubberneck]

Thanks for the reply with the part number, got 2 gaskets coming (cant hurt to have spare). The bolts were not loose, I just checked them not too long ago as a matter of fact. I guess the daily 50 psi trips as well as racing compact cars up the questa grade (with the trailer in tow of course) did the sucker in. Speaking of that, you should have seen the look on this guys face when i spanked him from a dead stop on hwy 46. he was in some sort of pos tiny car. he kept looking at me like i should let him go around. Oh well when the 2nd lane ended he was behind me and a big ol cloud of smoke. the correct torque on them is 18 foot pounds by the way, i think Bob was giving the torque specs for the intercooler boot clamps. So HVAC, i can do it without yanking the lines huh. sweet, that should make the job much quicker. Oh well, next week was going to be quality time with me and the truck anyway. New clutch going in, as well as a new super top secret fuel system. Need to see if i can rip the hitch clean off of the new fifth wheel

 

[Alan Reagan]

Rubberneck, You are right on the 18 ft/lbs for sure. I kinda thought with the boost you are producing, you had probably tightened them already. All trucks need to be checked after the 10,000 mile break in. If the gasket is deformed for any reason from lack of proper torque, when high boost is applied, it will probably blow.

 

[Mopar-muscle]

i've replaced mine also without removing the lines , i think i did pop off the front line from the head , that was the only one , bring it forward toward the radiator ...

 

[ADSmith]

I blew mine too-but I reinstalled with a very thin layer of silicone and have had no problems since.

 

[SOLER]

18 ft lbs? Is that it, or is it still two steps? I want to check mine.

 

[willyslover]

Phil. . do you have a inch pounds torque meter / wrench ??

or is that the Job that Blair is doing now ??..... anyway I have one you can use if ya need it. . I'm in Twain Heart. . could meet ya tomorrow in Stockton or Hwy 12 on way to Napa

 

[Bob Wagner]

18ft lbs is correct



the 2 step is for the boot clamps

 

[rubberneck]

Gary thanks for the offer, but i do have an inch pound torque wrench. Ill probably swap the gasket out monday cause that's my first day off. It seems to run fine anyhow now, just top end and boost have gone down and smoke is up. I was tired of all the mosquitos around here anyway