Pulled intake manifold to change gaskets

[Grube]

have had an oil leak running down back of engine. Couldn’t quite tell if was intake manifold or valve cover, decided to pull apart and do all the gaskets. Found some oil sludge buildup in valley. Looks like I’ve got some cleaning to do, and some hardware to replace.

How much sludge is too much? How far would you go with cleaning/maintenance if you opened the lid and saw this?

 

[95burban]

grab a few gallons of diesel and a stiff brush. Drain your oil after your done and one more time after driving it a few miles.

 

[movietvet]

That is a lot of sludge. New intake bolts, too. That sludge is in the lifters too. IMO, I would think seriously about an upper end teardown and address as needed. How many miles on this engine and I wonder how long between oil changes in the engine history, quality of oil and if the engine cooling system is working correctly? Is their an oil cooler on this engine? But, I also love spending OPM!

 

[Grube]

grab a few gallons of diesel and a stiff brush. Drain your oil after your done and one more time after driving it a few miles.

I’m gonna get a shop vac goin and try to suck up large pieces. Diesel brush is a good idea, I’ve got some around I can use.

I was even thinking maybe run some atf in with the oil get it hot then drain it right away.

 

[Grube]

That is a lot of sludge. New intake bolts, too. That sludge is in the lifters too. IMO, I would think seriously about an upper end teardown and address as needed. How many miles on this engine and I wonder how long between oil changes in the engine history, quality of oil and if the engine cooling system is working correctly? Is their an oil cooler on this engine? But, I also love spending OPM!

Haha, I like spending OPM too. With my own things, I won’t deny - I tend to cheap out a lot!

There is 315,000KMs, or 195700miles. I’ve only owned the truck since Dec 2023, and it had 17 owners before me haha. So I really can’t answer the oil changes or quality question. Cooling system is getting a new water pump and tstat during reassembly, all hoses replaced as they are cracking/aging. And flush the fluid. I was initially worried about lifters when I saw the gunk, but it did run well before disassembly (despite external leaks). The truck does have an oil cooler

 

[454cid]

grab a few gallons of diesel and a stiff brush. Drain your oil after your done and one more time after driving it a few miles.

I was thinking something similar, but gasoline instead of diesel. My thinking is that gas might be more likely to really liquefy the crap, and not leave clumps that could plug up the oil pickup. I've not done either, so I'm just extrapolating from when I cleaned some valve covers with gas.... stripped the baked on stuff nicely. Priming the oil pump with a drill would probably be a good idea after using gas. My experience with diesel is pretty much none, but I've found kerosene doesn't clean much for me.

This engine doesn't look as bad as the work van I got to see with the intake off, at a former employer. The mechanic (also shop owner) said he'd pick off as much as he could reach and spray it down, but he was afraid of getting too aggressive because the potential for clumps clogging things up. That van had had a bad intake coolant leak that we didn't see because the engine was run hard and would burn the water off.... engine oil would eventually turn red because of the dye in the dexcool.

 

[movietvet]

Haha, I like spending OPM too. With my own things, I won’t deny - I tend to cheap out a lot!

There is 315,000KMs, or 195700miles. I’ve only owned the truck since Dec 2023, and it had 17 owners before me haha. So I really can’t answer the oil changes or quality question. Cooling system is getting a new water pump and tstat during reassembly, all hoses replaced as they are cracking/aging. And flush the fluid. I was initially worried about lifters when I saw the gunk, but it did run well before disassembly (despite external leaks). The truck does have an oil cooler

Ok, your engine and your call, of course. When you fire it back up and the thermostat opens up and there is flow in the entire cooling system, I would use an infra red temp gun and check the core temps across several spots on the radiator.

 

[scott2093]

I’m gonna get a shop vac goin and try to suck up large pieces. Diesel brush is a good idea, I’ve got some around I can use.

I was even thinking maybe run some atf in with the oil get it hot then drain it right away.

I think the comment about the lifters being affected was good. My 93 didn't look nearly as bad and all the lifters were very caked up inside,,, They scoffed at overnight soaking in lacquer thinner so it was a chore to get them cleaned up.... But mine was more varnished than yours.....

Anyone have any thoughts on replacing the lifters by themselves?

 

[movietvet]

I think the comment about the lifters being affected was good. My 93 didn't look nearly as bad and all the lifters were very caked up inside,,, They scoffed at overnight soaking in lacquer thinner so it was a chore to get them cleaned up.... But mine was more varnished than yours.....

Anyone have any thoughts on replacing the lifters by themselves?

My opinion only. If I change lifters, I change the thunder stick.

 

[tayto]

i would consider dropping the oil pan and checking/cleaning it out. i could see the pickup being partially plugged with that much sludge in the valley.