So I am looking at a 2002 Disco II w/ 107k. Looks like drive shaft has been updated (grease fittings visible) and body is straight. Otherwise it's a little rough, especially inside. Anyway I understand Head Gaskets are an issue on these so I went ahead and ran compression test. Most checked out around 160-170 but 3,2 and 6 were more like 130. According to OBDII it is missing on 5 and 8 but both of these spec'ed out fine. So what do you think, is this a reasonable set of data?

BTW-no white smoke from exhaust and I ran a chemical test on coolant tank which indicated no presence of exhaust fumes in coolant.

Also brakes barely work, pedal sinks to floor and applies force to pads only once it has bottomed out, then there is some stopping power but not much.

Owner agreed to sell truck for $1500 btw... Good deal or no?

 

Did you do the compression test with all 8 plugs out and the t/body wedged open, if not your result are not accurate. You might want to do it again along with a wet compression test to see if 3,2 and 6 comes up.
If the compression does not average out better, I would start looking for another truck.

 

I think your numbers are fine, for that price buy it, spend the $500 and a weekend doing the headgaskets and you're back on the road.
With those 3 cylinders lower than the others by that much prob head gaskets ready to go, small leak just waiting to get bigger.

 

That's sort of what I was thinking. I could buy one for 5k and have the gaskets go 100 miles later since it seems to be imminent on these things anyway. This one just gives me a nice improvements budget!

Oh and no, I did not open the TB but did remove all plugs. Since TB was not open, should I expect actual readings to be higher?

 

do the test with the tb open and then do it again with a tablespoon or so of oil in each cylinder

 

Okay but if I re-run it and get same results, how bad is 130ish in your opinion?

 

Not bad, probably just leaky valves, nothing the local machine shop cant fix for an extra 100 bucks while he is resurfacing the heads.

 

put the oil in and you will know if it's rings or valves

Ps rule of thumb it 10-15% difference from highest to lowest

 

Thanks for all the input guys, really helpful! So I think I have decided to go buy the thing today... all indications are that the big/important pieces are there, just need to do a tune-up and some odds and ends.

So I've noticed that you are all crazy about replacing these head gaskets. Like, if there is anything wrong, replace gaskets! Do they really go bad THAT often? Easy job on these? Did the gasket on my 944 turbo a while back and it all come to like $1500 in parts alone and was a pretty big job, but there is a lot less room to work in those and a lot of hoses/pipes in the way.

 

I fear you will find out soon enough