2.8 Smoke and Pressure

Wolf Fabrication

Founding Member
There are a lot of threads on the interwebs on this subject, but thought I’d query the collective.

On a road trip from IL to MD my 2.8 started to expel white smoke mixed with some grey and I lost power going up hills. Turbo was still making boost at roughly 10lbs. Acts like it’s running on 3 cylinders. Pulling off the highway I was spewing white smoke. Temps remain normal and I’m not overheating. Exhaust isn’t sweet smelling.

Limped home. Visual inspection showed a loose valve cover and oil spewing from the front of the oil pan. PCV appears clear.

Tightening up the valve cover sealed the motor and now I have some strong pressure in the crankcase where it’s pushing oil out the oil pan and the oil filler cap can shoot off.

Running/idling cold there’s no smoke or oil leak. At temp it’s spewing white smoke, and at 2000rpm it’s pushing oil out the pan.

Before I start chasing a head gasket or IP timing, curious as to what your thoughts are.

Cheers!
 

Napalm00

Technical Excellence Contributor
Probably a blown head gasket at the push rod seal location. Remove the valve cover and start the engine look for exhaust chuffing out one of the pushrod holes.
 

Napalm00

Technical Excellence Contributor
It'll be apparent just by removing the rocker cover if you have a blown head gasket. No need to think about removing the head yet to identify where it's coming from.

But if you are pressurizing you're definitely getting engine compression somewhere into your oiling system.
 

Wolf Fabrication

Founding Member
It’s perplexing. The motor has less than 10k miles on it and wasn’t overheating. I maintained 200 degrees at speed on the highway in 95 degree heat. Higher than I want, but not significant. Chugging up the hills it would get to maybe 215, but immediately cool back down to 200.

It’s the loss of power, like even going up the hills by my house it chugs along.

I’ll pop the cover tonight and report back.
 

Napalm00

Technical Excellence Contributor
It happens man for sure. I just built a 2.8 from a 200 block and used ARP head studs instead of the bolts.

The fourth day after I moved here to Las Vegas I blew a bypass hose when I was 111° outside or something. I limped it home spraying coolant all over my brand new motor but it didn't warp and didn't blow.

If you rebuild it and decide to keep it and it's something as easy as a head gasket if you have $400 to blow I would just do the studs. I have my part number somewhere there's also a few guys overseas who've done it who I'm in touch with who have what I would think are better part numbers than the ones that I use

I'm running a peak boost pressure 35 PSI without issue using the standard 2.8 gasket. And I think I actually have an extra 2.8 gasket here at the house let me know
 

Wolf Fabrication

Founding Member
So hopefully found the issue, and something else didn’t cause this.

Found a broken tappet adjuster. This was on the #7 valve, which is intake. Push rod isn’t bent.

Also have a lot of wear on some of the rocker
arms.

The key question is, did timing belt slippage cause this?
 

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jymmiejamz

Founding Member
Callsign: KN4JHI
The last one I saw like that on a 200 Tdi I had assumed it was due to incorrect valve adjustment. Every other cylinder was way off
 

Napalm00

Technical Excellence Contributor
Wow that wear on the rocker arms is extreme. I can't imagine even the tops of your valves are in good condition.

All those rockers are going to have to be replaced and I just did this on a 300 TDI and it is not cheap. The little adjusting tappet is about $8.

If the tops of your valves are mushroomed at all they're going to have to be replaced as well. I recommend to most people to ditch the Land Rover lash caps and use the aftermarket empi 8mm hardened valve lash caps that are made for Volkswagens. They fit perfectly


This would not have been caused by timing belt slippage This is definitely caused by somebody setting the valves too tight or way too loose and the valves bashing against the rockers arms

I would go as far to say that if you end up replacing these items I would do a double oil change after they're replacement. Change the oil maybe 15 minutes 30 minutes run time after changing it again . There's a lot of cast steel in your system right now
 
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Wolf Fabrication

Founding Member
Wow that wear on the rocker arms is extreme. I can't imagine even the tops of your valves are in good condition.

Surprisingly the tops of the valves and caps are perfect! I'm replacing all the rocker arms and tappet adjusters. The motor was extremely loud from what I remember a 300/2.8 being (lots of top end noise) so this was the culprit. This was a "new" 2.8 from M&D with just under 10k miles on it.

I'll change the oil as well.

In my mind I am trying to walk through how I'd have smoke and more importantly pressure in the crankcase. Assuming #4 intake valve wasn't opening to allow air in it was just dumping fuel in and pushing it out the exhaust = white smoke. But it's the pressure that has me baffled. Can you explain that?
 

expanse

Well-known member
Pressure is coming form somewhere. rings or a HG blow out is where i'd be looking next. I'd pull the head and fully inspect; head, valves, valve seats, cam, followers, cylinders, etc. sucks to have this go on a fresh motor but sucks more to reassemble and still have an issue.
 

Wolf Fabrication

Founding Member
Pressure is coming form somewhere. rings or a HG blow out is where i'd be looking next. I'd pull the head and fully inspect; head, valves, valve seats, cam, followers, cylinders, etc. sucks to have this go on a fresh motor but sucks more to reassemble and still have an issue.

I'll do a compression test before I pull the head.
 

MountainD

Technical Excellence Contributor
Was the valve adjustment too tight do you think, keeping a valve slightly open allowing compression stroke pressure to escape?
 

Wolf Fabrication

Founding Member
Was the valve adjustment too tight do you think, keeping a valve slightly open allowing compression stroke pressure to escape?
Perhaps. This is why I am not going to pull the head immediately. I'll fix the rocker issue, test fire, and see if it's still pressurizing. No need to disturb the head....yet.
 

javelinadave

Administrator
Staff member
I believe you have two different issues. The one you uncovered and your overpressure situation. Your rocker/valve problem caused your overpressure situation but will not fix it. Only two culprits, the head gasket or your over pressuring the crankcase and its coming up thru the oil separator. My guess would be the head gasket as your motor is basically new. Good luck.
 

Napalm00

Technical Excellence Contributor
When you reassemble the rockers on the shaft pay close attention to the order of the shims. There are two thicknesses on there
 
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