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2.9L & 3.0L V6 Tech General discussion of 2.9L and 3.0L V6 Ford Ranger engines.

Engine Compression Test

Old 02-06-2016
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Join Date: Jan 2016
Location: Edmond, OK
Posts: 3
Engine Compression Test

I own a 2005 ford ranger 3.0 liter v6 I just recently did a dry compression test here are the results cylinder 1,2,3 are @ 150 psi 4,6 @ 120 psi and cylinder 5 @ 50 psi the engine only has 85k miles on it so I don't know what all this means cause I am no mechanic how much would it cost me to get this problem fixed? A mechanic had said I should just get a new engine with low miles on it at a salvage yard? Should I do this cause I know the labor will be expensive? But he had said even if he were to replace the valves he couldn't guarantee that it would fix the issue And also do I need a new battery? Because as soon as I was done and plugged everything back in I cranked the engine and next thing I know the airbag light comes on and there's a clicking sound or is the engine just flooded and if i need new valves how much would it cost me compared to getting a new engine? At a salvage yard also what do these numbers possibly mean and how much would it cost to get them all fixed? What will possibly happen if I decide not to get them fixed?
Old 02-06-2016
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Join Date: Jan 2014
Location: Vancouver, BC
Posts: 10,910
2004-2006 Ranger 3.0l engines had a problem with Recessed Exhaust Valve seats, which causes a loss of compression.
Fords TSB can be read here: http://www.ford-trucks.com/forums/88...placement.html

Your numbers point to this.

You can do a leak down test on #5
Leak down means you remove the spark plug and put piston at TDC, valves closed, then apply known air pressure, like 100psi, thru spark plug hole, and then read how much pressure will hold.
If it shows 90psi then you have 10% leak down which isn't bad.
But real reason for YOU to do this test is because you can listen at the exhaust pipe, and if you hear/feel air escaping then 100% confirmation on exhaust valve issue.

I would first check with local machine shops, a few, and see if they can install new seats and exhaust valves and how much, then also get them to price rebuild heads, both heads need to be done.

On ebay a set of 3.0l heads are listed at $320, plus shipping, so if local machine shop can fix yours or get you a set for $350 then that would be a fair price

You also need head gasket set($65) and head bolts(can't reuse these)($32), also coolant($15)
Many also change thermostat when doing this much work($10)

3.0l engine was very reliable, Rangers had them from 1991 to 2011, so literally millions are out there and still working, in Rangers and Taurus/sables

So redoing the heads would be worth while.
Swapping the engine is a gamble, usually not a bad gamble but you will have 0 history on the "new" used engine, it could have been over heated or internal parts stressed when running engine was suddenly stopped in an accident.
Used engines don't usually come from working vehicles, lol.

If you can't or don't want to o the work yourself, then shop time to do both heads, R & R(remove and replace), should be 8 hours, actually only takes 5 or 6.
Shops often like to supply all the parts, i.e. gaskets, bolts, and heads, some won't do the work unless they do supply parts.
This is because you would expect them to warranty the work, most people do, lol.
If you supplied the heads and there was a head problem.............who pays?
Or if a gasket, you supplied, failed?

But go in KNOWING the prices of the parts they will be supplying and ask for the prices of these parts upfront, if they seem out of line ask why, they will be "marked up" but 15% is normal, 100% is NOT.
Your truck, your money, YOUR CHOICE

Last edited by RonD; 02-06-2016 at 11:06 PM.
Old 01-11-2018
Join Date: Nov 2017
Location: Pasadena, California
Posts: 94
I know this is an old post but, did you ever get the airbag light issue fixed?
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