How long do B5.9 head gaskets last?

[Ncostello]

I'm at 199,999 stock power miles and don't seem to be having any issues. But is there an age or mile limit on an original head gasket? I'm planning on removing the injection pump, injectors and exhaust manifold later this spring... and was wondering about the head gasket while I'm in the area. I know it's quite a bit more work than what I'll be doing but it makes sense if it'll be tore down this much and they are known to age and later fail.

 

[DVolk]

I use the old rule if it isnt broke don't fix it , Its not uncommon to see these engines way over 300 k so i wouldnt
pull it down and if your going that far you just as well by a rering set and put rings and bearings in .

 

[Slow Six]

There are all kinds of the old 5. 9s with way more miles than that and never been touched. Like DVolk said if it's not broke don't fix it.

 

[fox]

Wait until it goes past 1,000,000 to even worry about it unless you have a lot of fuel fed to it.

 

[Ozymandias]

Never touch a fine running System - its a CUMMINS Truck Engine, not an ordinary burnt out Car Engine.
Enjoy next 200 MM

 

[RSchwarzli]

Yeah, I would not worry too much! Unless high boost or abused, you will likely be fine!

 

[HHhuntitall]

I wouldn't think there are any problems, either. Only thing I would do is check the torque on the headbolts, and move on with it. Most of mine have more than that on 'em, and don't leak too bad... .

 

[Shadrach]

I say leave it as well. Unless there is some antifreeze leaking near the thermostat it generally isn't a problem with your year. Be very careful removing the exhaust manifold as the bolts tend to break because the manifold shrinks. Just look at the end bolts and see if any of them are not "straight" - that is leaning towards the center of the manifold. Soak them down good for several days before hand and go easy removing them. Are you replacing the manifold or just leaking gaskets? There are several good after market manifolds available, both in single piece and multi piece. Also would be a good time to loose that 21 cm hsg Shad

 

[Ncostello]

I'll leave the head gasket well alone. I didn't think it was a problem child... . at least I've never heard any discussions on it. Just checking.



I will be very careful removing the old manifold. Thanks for the tips. I plan on a 3 piece unit. And I'd like to use some good quality studs like ARP if they are available. And get a manifold pre-drilled for an EGT gauge. My OEM exhaust maniford gasket is leaking at the #1 cylinder. I can see some exhaust trails around it.



For the turbo I will be getting a rebuild on the H1C for good measure... while installing a 14cm non-wastegate housing (short exhaust flange hopefully). The 21cm is big just looking at it. It's gotta go.

 

[Shadrach]

I'd go with a 16 cm hsg, much more common and the 14 might be to much if yours is a stock engine. We all know when you pull a head off you end up going deeper just because your there Once you open the can all the worms want out. Shad

 

[Joseph Donnelly]

Occasionally with engines up to about 1996, you get an antifreeze leak near the thermostat housing or in the rear. The replacement "marine" type gasket was the fix.

 

[DVolk]

To add to Joes commit only use Cummins thermostats as the non oem ones cause many issues

 

[BarlowCummins]

500,000 here and still ORIGINAL head gasket.

 

[Ncostello]

I'll look into the 16cm housing. The only coolant leak I have is the water pump oring. I need to clean the groove out better and try it again. I installed a new water pump and Cummins thermostat but I think the oring groove should have been polished better. There isn't much "crush" to the new square cut oring. So it want's to seep sometimes. Maybe a film of valco sealant on the mating surfaces and a day or so to dry would help.

 

[HHhuntitall]

I'll look into the 16cm housing. The only coolant leak I have is the water pump oring. I need to clean the groove out better and try it again. I installed a new water pump and Cummins thermostat but I think the oring groove should have been polished better. There isn't much "crush" to the new square cut oring. So it want's to seep sometimes. Maybe a film of valco sealant on the mating surfaces and a day or so to dry would help.

I put a little silicone in 'em when they've got a lot of rust. The pitting will cause seepage if you don't put a little something in there.