We have a 99 Disco 2 and it is running really rough. I had a mechanic buddy look at it and he did a compression check and found one cylinder only held 25 psi, he mentioned I might have a "burnt valve". So I have changed the oil and added some SeaFoam to the oil, I also added some Lucas Injector cleaner to a tank full of gass. I tried to inject some Seafoam into the intake but the engine kept on stalling. I am trying to avoid pulling the head and getting repaired. Any suggestions would be greatly appreciated. Thanks

 

have a cylinder leakdown test done. this will tell you where the air is going and lead u in the rite direction.

 

Not sure what the additives were supposed to help. Get it into a trusted mechanic and plan on a valve job, there is nothing else it can be other then a cracked head, either way, it is time for an upper tear down.

 

thanks guys

 

don't put seafoam in the oil.

The reason your truck was stalling on the intake was you were pouring it in too fast. Slowly. But it won't help your exhaust valve, which is the one that has the damage.

Oh, and never run 87 octane, only 91, or this will happen again.

 

auto-rx.com if it is a sludge problem, sludge is known to lower compression in cylinders. Lucas fuel additive is Nothing more than a Fuel System Lubricant. It does NOT clean anything in the fuel system. You can't lube a dirty system. If you want to clean the system use either Redline Fuel system cleaner, Gumout Regane Fuel system cleaner (caramel color), or Chevron Techron concentrate.

 

If you are talking about getting rid of sludge, do an engine flush and be done with it, there are no gas additives that will actually break down sludge.

 

A sticky valve can cause low compression because the valve is not closing when it is supposed to.

 

I am trying to do everything I can with my limited mechanic skills before I have the top end rebuilt. What suggestions do you guys have? I am a little nervous about an engine flush b/c I have heard things get plugged up from the loosened sludge. How can I avoid this and how can I free a sticky valve if that is what it is? Thanks

 

If you are not willing to listen to 30 years of experience, you posts are a waste of both your time and ours.
There is no vodo magic that is going to help you with this problems, the heads need to come off, early D2's had issues with valve guide failures and yours will most likely be one of them, so quit wasting your time and have it torn down.