Cat 3176 Head gasket issues..HELP!

[pa_of_6]

Hello All

So I have a Freightliner with a 3176 Cat in it.\These engines were famous for head gasket issues...and mine has fallen victim to that issue.

I would like to replace the headgasket myself, but am wondering what kind of issues I may run into.

So any of you folks that have worked on the 3176 Cat engine I would appreciate you input.
Thanks in advance

[colroggal]

Is it just staining the block or making oil?

[pa_of_6]

Its blowing out thru the rad.

I did my 6.7 cummins in my dodge and it wasnt too bad a job and no surprises...

[colroggal]

Not a lot to say. It's time consuming but doable. Just to be sure, I'd draw some oil and test it just to be sure you're not blowing down into the pan. If the mains go it won't be worth your time. There are plenty of pre emission petes still floating around out there. Just about bought an '05 last week with 55k on a new motor. Old bugger decided not to retire.

Colin

[dangerranger5143]

Originally Posted by pa_of_6

Hello All

So I have a Freightliner with a 3176 Cat in it.\These engines were famous for head gasket issues...and mine has fallen victim to that issue.

I would like to replace the headgasket myself, but am wondering what kind of issues I may run into.

So any of you folks that have worked on the 3176 Cat engine I would appreciate you input.
Thanks in advance

Definetly doable with some mechanical experience and the proper tools. I’ve rebuilt many C-12, C-13 and C-15s. All of them have their differences and similarities.

With yours have you bottle tested it for combustion gases in the cooling system? One other thing it could be is the air compressor pressurizing the cooling system. Wouldn’t hurt to isolate the compressor to be sure it’s not that.

Other possible causes are a cracked cylinder head or a low cylinder liner protrusion. Cylinder head would be as easy as just replacing. Low liner would require more work, money and some specialized tools.

Any further questions feel free to ask or PM me.

DR

[hayseed]

What exact symptoms??
Obviously antifreeze, but blowing out?
Antifreeze in the oil??

[leadpillproductions]

Make sure its just not your compressor pushing air into block , Just undo compressor line . Run a hose from rad over flow to bucket of water. With compressor line off , if air still making bubbles , head gasket , if no bubbles its your compressor. Engine needs to be up to temp

[dangerranger5143]

Originally Posted by leadpillproductions

Make sure its just not your compressor pushing air into block , Just undo compressor line . Run a hose from rad over flow to bucket of water. With compressor line off , if air still making bubbles , head gasket , if no bubbles its your compressor. Engine needs to be up to temp

I would recommend to isolate the compressor from the cooling system completely. Just unhooking the discharge line does not remove it from the system. The compressor can still be cycling and introducing compressed air into the cooling system.

DR

[hillbillyreefer]

Originally Posted by leadpillproductions

Make sure its just not your compressor pushing air into block , Just undo compressor line . Run a hose from rad over flow to bucket of water. With compressor line off , if air still making bubbles , head gasket , if no bubbles its your compressor. Engine needs to be up to temp

Originally Posted by dangerranger5143

I would recommend to isolate the compressor from the cooling system completely. Just unhooking the discharge line does not remove it from the system. The compressor can still be cycling and introducing compressed air into the cooling system.

DR

Could you guys be a bit more specific on how to isolate the compressor? I’ve got a 3208 blowing coolant out the rad cap. It only does it once the system has pressured up for a few minutes, not immediately on start up, I’m hoping it’s the compressor.

[gmcmax05]

Originally Posted by hillbillyreefer

Could you guys be a bit more specific on how to isolate the compressor? I’ve got a 3208 blowing coolant out the rad cap. It only does it once the system has pressured up for a few minutes, not immediately on start up, I’m hoping it’s the compressor.

Bypass coolant going to the compressor.

[dangerranger5143]

Originally Posted by hillbillyreefer

Could you guys be a bit more specific on how to isolate the compressor? I’ve got a 3208 blowing coolant out the rad cap. It only does it once the system has pressured up for a few minutes, not immediately on start up, I’m hoping it’s the compressor.

There will be two coolant lines running to the compressor. One feeding coolant to the compressor and one returning back to the engine. To bypass it means to eliminate coolant flow going to and from the compressor.

What happens if the compressor has a failed head gasket is the air it is compressing for the truck gets pushed into the coolant system and over pressures the road cap. Same symptoms as a faulty engine head gasket(coolant coming out the overflow).

I would recommend running the engine to operating temp before bypassing the compressor. If you bypass it first then try and to run it up to temp you run the risk of overheating the compressor and causing yourself more problems.

DR

[gmcmax05]

Originally Posted by dangerranger5143

There will be two coolant lines running to the compressor. One feeding coolant to the compressor and one returning back to the engine. To bypass it means to eliminate coolant flow going to and from the compressor.

What happens if the compressor has a failed head gasket is the air it is compressing for the truck gets pushed into the coolant system and over pressures the road cap. Same symptoms as a faulty engine head gasket(coolant coming out the overflow).

I would recommend running the engine to operating temp before bypassing the compressor. If you bypass it first then try and to run it up to temp you run the risk of overheating the compressor and causing yourself more problems.

DR

Or you could hook up an external cooling source (garden hose) to avoid having to disconnect coolant lines @ 180*+.

[hillbillyreefer]

Thanks guys, I appreciate the info. I didn’t realize the compressor was liquid cooled.

[dangerranger5143]

Originally Posted by gmcmax05

Or you could hook up an external cooling source (garden hose) to avoid having to disconnect coolant lines @ 180*+.

That’s a good idea. Hadn’t thought of doing it that way. Good point.

DR

[Tfng]

Make sure it's not just a failed rad cap.

You may have to drive the unit at full load to prove the gasket is leaking if it isn't severe. High boost pressure increases cylinder pressure. In the case of a slight leak you may not find the fire ring split/cracked/blown out but you will find a dark discoloured area of the fire ring. Most often cylinder five or six. Pay special attention to the liner in that hole. It's unlikely you have a liner protrusion issue on that engine but checking is part of doing a good job.

3176 has copper injector cups swaged in place which require specialized tooling to replace. I'd consider having them replaced while the head is off. If the price is within reason, consider a reman head. I saw enough failures when this engine was common.

Carefully inspect the cam followers and cam. The followers can only be replaced with the head off. If you find the cam worn, do the front structure as well.

3176 is hard on rocker arms, inspect the tips.

Check for bent push tubes.

If you reuse the cylinder head make sure it's flat and free of fretting in the fire ring area.

I'm pretty sure I remember there is an updated procedure to replace the headbolts and a change in torque but I'd have to look into that to be certain it applies to the 3176.

Tap the head bolt holes in the block to clean the threads to increase accuracy of torquing them down.

I've never concerned myself with an external cooling source for the compressor as long as there's no load on it. It's just coasting up and down and still has oil going through it. Without compressing air there's minimal heat created.

[pa_of_6]

Well...You know I never even thought about it being my air compressor that is causing the problem.

I will have to check that out.

Actually I am giddy at the thought that it is my air compressor,

And when I thought about it many times, it just didn't present itself like ahead gasket leak.

Usually a head gasket leak will cause high temps and this never did cause that.

I thank you all for the valuable info, great reason to be on this forum.

It may still be the head, but I will have to check it out.

[dangerranger5143]

Originally Posted by pa_of_6

Well...You know I never even thought about it being my air compressor that is causing the problem.

I will have to check that out.

Actually I am giddy at the thought that it is my air compressor,

And when I thought about it many times, it just didn't present itself like ahead gasket leak.

Usually a head gasket leak will cause high temps and this never did cause that.

I thank you all for the valuable info, great reason to be on this forum.

It may still be the head, but I will have to check it out.

Let us know how you make out. Good luck.

DR

[pa_of_6]

Well it looks like it is the head gasket.


So going to have to replace it.

Any tips before I start??

[Bigwoodsman]

Originally Posted by pa_of_6

Well it looks like it is the head gasket.


So going to have to replace it.

Any tips before I start??

I owned a couple of these. Best thing to do is fix it then sell it and get anything but.

BW