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mikes landscaping
04-28-2007, 11:29 PM
I just bought a 1999 ford ranger supercab 4x4 with the 3.0 v6. i got a great deal on it, for only 1200 bucks. it has 114,000 miles on it. Everything on the truck is perfect, almost lol. It has a compression problem in the fourth cylinder. my question is, would it be cheaper to get the head re bored, or what might my other options be? thanks
-Pete

Dirty Water
04-29-2007, 05:44 PM
A compression problem can stem from a handfull of symptoms.

You could have a chipped exhaust valve, which would prevent sealing and allow compression loss.

You could have bad rings on the cylinder which would make the compression go into the crankcase.

You could have a blown headgasket and you'll see the engine compression push into the coolant.

Before you tear an engine down, you need to do a leakdown test to see wher the problem lies.

Best case scenario is you will pull the head and change the gasket, but I doubt it. You have to pull the head regardless, so have the head inspected by a quality shop to make sure the valves are ok and the head is not cracked.

If it is from bad rings, you should probably do a full rebuild, as you will pull the pistons and hone the cylinders, replace the crank and rod mains, replace the rings, and have the head off anyway.

mikes landscaping
04-29-2007, 06:12 PM
ok, thanks for the info, but then i also have the option of a junkyard engine for $500, with 70-80 thousand miles? would you just go for this?

Dirt Digger2
04-29-2007, 07:01 PM
i would say the first thing to do if you take the head off is to look to make sure all the valves are seating...in my old tractor the exhaust valve in cylinder #3 isn't seating so its losing compression but i sure wouldn't have anything rebored until you have to

topsites
04-30-2007, 09:14 AM
It depends how bad a compression problem it is... I had an older '87 VW Golf with that problem but you really couldn't tell other than it didn't sprint like it used to, but no missfire or nothing, and I just drove it till it quit lol. It was getting something like 50 psi instead of 90 on the number 4 cylinder (I don't remember the exact specs, but about half of normal), the rest of the engine was fine, so I just drove it.

That's what I would do, for $1200 I would just drive it, again so long it's not such a big loss that it affects the engine.

mikes landscaping
05-01-2007, 11:46 AM
It depends how bad a compression problem it is... I had an older '87 VW Golf with that problem but you really couldn't tell other than it didn't sprint like it used to, but no missfire or nothing, and I just drove it till it quit lol. It was getting something like 50 psi instead of 90 on the number 4 cylinder (I don't remember the exact specs, but about half of normal), the rest of the engine was fine, so I just drove it.

That's what I would do, for $1200 I would just drive it, again so long it's not such a big loss that it affects the engine.

well the truck needs to be registered and ionspected, so theres no way it will pass inspection in this state of disrepair lol.