2002 ISC 350 Manifold Removal

[crah]

I'm in the middle of removing the Manifold amd taking a break, and things are going too well. I think I spent more time putting down protection paper in the bedroom than removing the bolts. I have have a couple of questions. All the bolts came out without breaking. One of the bolts is stud with a nut instead of a bolt. What is the purpose of that 1 stud? The turbo mounting plate nuts are a little hard to get at. I have two loose but the other 2 seem nearly impossible to get at. The nuts are on the bottom of the plate. Is that how it is supposed to be? It would seem to make more sense for them to be on top. Looking at the new parts, it looks like 4 studs with threads on both ends. How exactly do they go on? Looking at pointers on removing the last two nuts. See the attached pictures looking down from top. I read that I should hang the turbo from something. Looking at the picture, it seems it would support itself as it is connected from both sides. Pointers on removing the last two nuts and explanation of how the studs work would be appreciated.

[dennis45]

When I changed mine a year or so ago, I removed the Turbo with the manifold. I decided to remove the Exhaust Brake Valve and clean it up at the same time. So rather than fight with rusty bolts upside down, I pulled it in one piece.
So, I replaced both E Brake Clamps and gaskets and new Turbo Lube Oil Line.
Not sure what the one stud is for, I did not have one but it would be handy to hold the manifold in place to get the rest of the bolts started.
Be sure to torque all bolts to spec. Can't remember what is was. Sorry,
When you go to install the Turbo oil line, pour or squirt some oil down the lube oil inlet on the Turbo to ensure oiling on start up.
Last thing you should do is take the coach for a spin to get things hot and before you cover the access, re-torque all bolts again while hot.

[palehorse89]

Hi Craig, I removed all 4 of the nuts and lock washers and removed my turbo from the exhaust manifold. Mine had studs in the manifold for the turbo. All the manifold bolts were bolts w/spacers on them, no stud with nuts. As a suggestion, due to extreme heat and being 10 yrs. old I would replace anything you can while it is apart. I bought all new bolts w/new spacers for the manifold and of course all the gaskets needed. I assume you are going to a Cummins dealer to order all the parts you need? Cummins OEM are the best and safest way to buy parts for your engine. You are right about those 2 nuts on the turbo on the back side......a bit of a challenge to get to as you can just do it by feeling them, but you will get them off. Good luck

[dennis45]

Originally Posted by palehorse89

Hi Craig, I removed all 4 of the nuts and lock washers and removed my turbo from the exhaust manifold. Mine had studs in the manifold for the turbo. All the manifold bolts were bolts w/spacers on them, no stud with nuts. As a suggestion, due to extreme heat and being 10 yrs. old I would replace anything you can while it is apart. I bought all new bolts w/new spacers for the manifold and of course all the gaskets needed. I assume you are going to a Cummins dealer to order all the parts you need? Cummins OEM are the best and safest way to buy parts for your engine. You are right about those 2 nuts on the turbo on the back side......a bit of a challenge to get to as you can just do it by feeling them, but you will get them off. Good luck

Palehorse, we meet again.
I forgot to mention new bolts and use a little Never Seize when installing. I agree OEM parts are the way to go. Yes, when doing a job like this, do it right so you don't have to do it twice. I also installed a banks kit at the same time but that is no longer an option.
I noticed the new manifold had some extra material that hopefully will help it last longer.

[palehorse89]

Originally Posted by dennis45

Palehorse, we meet again.
I forgot to mention new bolts and use a little Never Seize when installing. I agree OEM parts are the way to go. Yes, when doing a job like this, do it right so you don't have to do it twice. I also installed a banks kit at the same time but that is no longer an option.
I noticed the new manifold had some extra material that hopefully will help it last longer.

Hello there Dennis, And yes , good advise on the never-seize but NOT TO MUCH as they will tend to come loose after heating and cooling and it acts like a lubricant on the threads and changes the torqueing values. I had 2 that kept coming loose so I took them out and put a lock washer on them and that stopped them from coming loose. If I was doing it again I would put a lock washer on all of the manifold bolts (between the bolt head and the top of the spacers) to prevent any loosening problems that might arise. The spacers are there to absorb the heating and cooling (expansion and contraction) of the bolts to prevent them from snapping off in the head of the engine. Also the torque specs. for the bolts seems really low to me and after a couple heating cycles and running the engine all of them seemed to loosen, so I forgot the torque specs. and tightened them down and have not had a problem with them again. Finally I don't have to check them no more. To the OP: I have the torque values for all that you are working on if you need them.

[crah]

Thanks for the pointers. I have all new gaskets including for the turbo and drain tube as well as all new bolts and spacers.

How are the studs attached to the manifold? I'm thoroughly confused why they are threaded on both sides of the stud. Is the mounting plate in the turbo Un threaded so the stud slips through.

Torque specs would be appreciated.

[dennis45]

Originally Posted by crah

Thanks for the pointers. I have all new gaskets including for the turbo and drain tube as well as all new bolts and spacers.

How are the studs attached to the manifold? I'm thoroughly confused why they are threaded on both sides of the stud. Is the mounting plate in the turbo Un threaded so the stud slips through.

Torque specs would be appreciated.

The studs are threaded on both ends. One end screws into the manifold then the gasket installed. Next slide the Turbo housing over the studs, install the nuts and tighten to spec.

[palehorse89]

Originally Posted by crah

Thanks for the pointers. I have all new gaskets including for the turbo and drain tube as well as all new bolts and spacers.

How are the studs attached to the manifold? I'm thoroughly confused why they are threaded on both sides of the stud. Is the mounting plate in the turbo Un threaded so the stud slips through.

Torque specs would be appreciated.

I am thinking that the holes in my manifold were threaded and the studs screwed in to it for the turbo mounting w/ lock washers and nuts on top. I did not remove the turbo studs from the manifold.

Cummins 6CT 8.3 Torque Secifications
Component
ft lbs
Aftercooler mounting
18
Alternator pulley Nut
59
Belt tensioner to bracket
32
Cam thrust plate
18
Connecting rod
　step one
33
step two
60
step three
88
Crankshaft damper
148
Crossover clamp
4
Exhaust manifold
32
Exhaust outlet pipe mounting
32
Exhaust V-band clamp
9
Fan bracket mounting
18
Flywheel
101
Flywheel housing
45
Fuel banjo screw in filter head
18
Fuel vent screw in banjo
6
Fuel low pressure supply at pump
11
Fuel low pressure return at pump
11
Fuel filter adapter nut
24
Fuel high pressure line fitting
18
Fuel pump drive gear (A)
60
Fuel pump drive gear (MW)
66
Fuel pump lock
11
Fuel pump mounting nut
32
Timing gear cover short bolts
18
Timing gear cover bolts long 10.9
29
Gear housing to block 10.9
29
*Cylinder Head Bolts
　step one
37
step two
110
step three
148
Injector drain manifold
7
Injector retaining capscrew
18
Intake manifold cover
18
Lift pump mounting
18
Main bearing cap
　step one
37
step two
88
step three
129
Oil coler cover
18
Oil pan drain plug
60
Oil pan mounting
18
Oil pressure regulating valve
60
Oil pump mounting
18
Oil suction tube flange
7
Oil suction tube brace
7
Rocker support
32
Rocker lever nut
18
Starter motor
57
Thermostat housing
18
Timing pin flange mounting
4
Turbo mounting nut
24
Turbo drain tube
18
Turbo oil supply fitting
18
Water pump mounting
18
Valve cover
18

*Cylinder head bolt torque is for early production engines. Newer head gaskets require torque plus turn. Engine serial number required for proper torque. Contact me for more information.

[crah]

Originally Posted by palehorse89

I am thinking that the holes in my manifold were threaded and the studs screwed in to it for the turbo mounting w/ lock washers and nuts on top. I did not remove the turbo studs from the manifold.

Cummins 6CT 8.3 Torque Secifications
Component
ft lbs
Aftercooler mounting
18
Alternator pulley Nut
59
Belt tensioner to bracket
32
Cam thrust plate
18
Connecting rod
　step one
33
step two
60
step three
88
Crankshaft damper
148
Crossover clamp
4
Exhaust manifold
32
Exhaust outlet pipe mounting
32
Exhaust V-band clamp
9
Fan bracket mounting
18
Flywheel
101
Flywheel housing
45
Fuel banjo screw in filter head
18
Fuel vent screw in banjo
6
Fuel low pressure supply at pump
11
Fuel low pressure return at pump
11
Fuel filter adapter nut
24
Fuel high pressure line fitting
18
Fuel pump drive gear (A)
60
Fuel pump drive gear (MW)
66
Fuel pump lock
11
Fuel pump mounting nut
32
Timing gear cover short bolts
18
Timing gear cover bolts long 10.9
29
Gear housing to block 10.9
29
*Cylinder Head Bolts
　step one
37
step two
110
step three
148
Injector drain manifold
7
Injector retaining capscrew
18
Intake manifold cover
18
Lift pump mounting
18
Main bearing cap
　step one
37
step two
88
step three
129
Oil coler cover
18
Oil pan drain plug
60
Oil pan mounting
18
Oil pressure regulating valve
60
Oil pump mounting
18
Oil suction tube flange
7
Oil suction tube brace
7
Rocker support
32
Rocker lever nut
18
Starter motor
57
Thermostat housing
18
Timing pin flange mounting
4
Turbo mounting nut
24
Turbo drain tube
18
Turbo oil supply fitting
18
Water pump mounting
18
Valve cover
18

*Cylinder head bolt torque is for early production engines. Newer head gaskets require torque plus turn. Engine serial number required for proper torque. Contact me for more information.

Thank you for the info. I see you have the mechanical 8.3. I wonder if there were any changes from 8.3 ISC? I plan on leaving my turbo in place as well. Long as I can get the remaining two nuts off, it should work. Did you use a special tool to get to these nuts? I'm using a 15mm box wrench, but not having much success with the remaining two.

[palehorse89]

Originally Posted by crah

Thank you for the info. I see you have the mechanical 8.3. I wonder if there were any changes from 8.3 ISC? I plan on leaving my turbo in place as well. Long as I can get the remaining two nuts off, it should work. Did you use a special tool to get to these nuts? I'm using a 15mm box wrench, but not having much success with the remaining two.

If I remember right(3 years ago) I had to hold the turbo up a bit to get the nuts off the studs. I more than likely missed it but is blown out gaskets the reason for this job?

[crah]

Not sure I can lift the turbo up without disconnecting it from the cac tube and the exhaust brake.

I'm replacing because I have a leak on a couple of the gaskets and my exhaust brake recently became less effective.

[palehorse89]

I have an electronic ISC engine with a computer controlled injector pump. This system is the Cummins Accumulator Pump System (CAPS) and the CAPS is controlled by the ECM (Electronic Control Module).
The problem that you are running into is why I took the turbo right out of there and everything around it, I had one broken off bolt in the head and needed the room to do the job.

[Yukon Jack]

crah
When I replaced my exhaust manifold this spring, I had the same situation, wherein there was one or two bolts for the exhaust manifold that appeared to be a stud, but once you get it out, it is a special bolt with a threaded stud on top of the hex head of the bolt. In my case I could have eliminated it and used a standard manifold bolt, but I already had the bolt kit from Cummins, so I reinstalled as an OEM set up. I was advised by Cummins it was for an application that I did not have on my 2001 ISC350 engine and it was not actually necessary to use it if I didn't want to.

As indicated by others, I would strongly recommend using all new OEM hardware from Cummins for reliability purposes. In my case, with a cracked manifold, I also I stalled a new oil lube line, as i had hot exhaust gases blowing on the oil line and I did not want this pressure line to spring a leak, which if that atomized oil would come in contact with a hot turbo, a fire would likely result.

As a suggestion, I would strongly recommend doing as I did, and that was to chase the threads in the head and turbo mounting flange on the exhaust manifold, then blow clean with compressed air. It makes reassembly much easier and provides the comfort of mind that you are able to apply a truer torque value to the mounting hardware.

Relative to the exhaust manifold bolt torque, i found out that the Cummins service techs are pretty tight-lipped about that I formation due to past liability issues they had encountered with RV owners doing their own work, and subsequently broke manifold bolts and then blamed Cummins for giving incorrect torque values.

All that aside, the torque values I was given was :
Exhaust manifold bolts (10 mm x 1.5 pitch) = 39 ft-lbs.
Turbo mounting stud nuts = 33 ft-lbs.

Hope this helps and Happy RVg and best of the holiday season

Jack

[crah]

So in order to remove the turbo, all I need to do is remove the band clamps near the cac tube and the exhaust brake? Are there any gaskets to these connections?