2350 front structure gasket

[Mattman]

What is the ball park figure on getting a shop to replace front structure gasket for an oil leak?

Looking at a used truck with the left front corner oil drip.

[Rawze]

You need to find out why it started leaking in the first place. Leaky gear cover gasket at the top is often a sign that cam bearings in the head may be worn out.

[Mattman]

The leak appears to be down on the left front corner. From the looks of it the oil isn't running down from above. Maybe leaking 4 inches or so up from the bottom of the block.

[SquareOne]

What’s the mileage? Rawze is just saying make sure you don’t have excessive internal pressure , or enough wear to bias one side of a seal. At that point, , problems would be more severe than just a leak. It would also give you an idea of general engine condition...

Def know before you buy!

[Signature620]

Front and rear housing gaskets are very common failures on cm2250/cm2350 ISX engines. I believe they changed supplier or material for the rubber in the gaskets and it eroded easily.

There was a bulletin released in Australia that instructed techs to replace the gasket then run a bead of RTV down the intake side of the block after the gear housing is refitted.

Personally, I apply a very light amount of RTV to both sides of the steel section of the gear and flywheel housing gaskets. Others use anaerobic sealants like Loctite Master Gasket.

I can't comment on job pricing in countries other than Australia.

[Chamberpains]

Cummins isx torque to the exhaust side(right). A crack on the left side is usually a sign that someone torqued and tortured the engine pretty hard to twist that side enough to break something. Or best case scenario, an engine mount came loose and allowed the engine to twist. But I'd go with the previous and assume it was beat pretty hard. I'd leave that one be. Plus the whole front of the truck and the engine has to come apart to do a gear case. Probably close to a 16-20 hr job in mostly labor cost.

[Mattman]

Truck has about 515,000 miles and 11,000 hours. Does have a little blow by, but I am not sure which crank case filter it has or last time it was replaced.

I don't believe anything is actually cracked. Seen a video of the structure gasket. Looks like not much of a gasket at all. Have asked around front and rear structure oil leaks seem to be fairly common around 500,000 mark.

Like others have mentioned it is labor intensive.