Hello Ranger Forum,

2004 Mazda B3000 DS

New heads, lifters, and timing chain were replaced at 155k miles. My truck now has 166k miles and all is working good with no check engine light or misfires.

Yesterday, I ran the compression tests just for my own benefit to see what the readings were after the heads were replaced.

Engine was cold and I added 1 teaspoon of oil in each cylinder for the wet test.

Results:

Cylinder Dry Wet
------------------------------
1 180 190
2 180 195
3 180 190
4 180 200
5 195 215
6 180 195

Cylinder 5 is higher then the rest. Do you think this is anything to be worried about?

Thanks ahead of time.

Jeff

 

Is there any "ticking" noise at idle?

Lifters have a spring inside to hold pressure against pushrod and rocker until oil pressure takes over
Its possible to have a bad spring on an exhaust valve lifter so when cranking over on compression test the exhaust valve has delayed opening and early closing which would increase compression reading in that cylinder
But you would often hear a "popping" noise when testing that cylinder, from escaping pressure when intake valve opened, but not always

It wouldn't be a big concern since oil pressure is what is used to hold up lifters when engine is running, and if there is no ticking noise then all is well

 

Yes Ron there is ticking noise at idle!

And I have heard a popping sound once in a while on start up.

Oil pressure runs from 10pst to 60psi depending on engine temp and rpms.

 

Then you most likely have a bad lifter on that one cylinder, exhaust valve

Not sure on the 3.0l Vulcan if you have to pull the head to change a lifter, on the 2.9l and 4.0l you did
On some of the pictures it looks like the pushrods do go thru the head so there may not be enough clearance to pull out a lifter with just the valve covers and lower intake removed

It wouldn't be an urgent fix, it won't cause any engine damage

 

Thank you Ron for your detailed insight.

Just having to remove the valve covers and lower manifold would not be to bad.

Looking at this picture I took during the head install, thinking I can replace the #5 cylinder exhaust lifter without removing the heads:

 

Yes, it looks way different than the pictures I saw of what was IDed as the 3.0l

You can test for lifter issues by removing spark plugs(so you can turn engine easily)
Then rotate crank so both valves are closed on a cylinder(watch rockers and lifters)
Then try to spin the pushrod with your fingers, should be barely doable with a good grip, lol
If it spins easily then lifter is bad

Test a few and you will get a "feel" for it

You can get a new set of 12 lifters for about $100
But replacing just 1 or 2 is OK as well, these are not high failure devices
Soak new lifter in oil for 60min or so

After new lifter is in and rocker assembly torqued down, crank engine over, no spark plugs, to get new lifter(s) pumped up
Then do finger test again

Be careful when hooking battery back up those alternator wires are LIVE

 

Sweet, I will purchase a few lifters and then do the pushrod spin test.

For this tasks:
"After new lifter is in and rocker assembly torqued down, crank engine over, no spark plugs, to get new lifter(s) pumped up"

Assuming manually turning crank thru a few rotations with socket and wrench on crank pulley?

 

No you have to use starter motor to get oil pump up to speed to send oil into the lifters

You can jump the starter relay in engine fuse box

And its not "required" to do this at all, just for testing, so you can skip it and just reassemble

 

I would like to do that test by cranking the engine, but with the valve covers off, wouldn't oil spray everywhere?

 

It can, I would lay the valve cover over each side just in case, and put a towel down across exhaust manifolds as well in case there is run off

I have rocker arm oil deflector clips from the old days when you had to adjust each rocker with engine running, yes I am old

 

That is awesome, thanks so much Ron for your insight. I now have a game plan to fix the remaining engine issue.

 

Yes, you can replace the lifters without removing the heads. But... You may run into difficulty removing the lower intake unless you remove some pushrods. The way the lower intake is shaped, some of the spots where the push rods pass through are a bit tight, like an almost closed loop around the rod. I was never patient enough to try removal with all the rods in, nor to see which ones were the hold up. lol Another thing you will find is it is easier to just remove all the push rods to re-gasket for the lower intake and install the intake before installing the push rods. If you do this, you must carefully install the push rods to insure they are properly seated. Have a magnet ready in case you let one slip out of your fingers. lol. YMMV

 

Thank you Grumpa for the recommendations.

I do plan to remove the lower manifold to replace cylinder 5 exhaust lifter and perform the pushrod twist test this time and on all lifters. And agree the pushrods have to be take out on a few cylinders to get the lower manifold off and back on.

I replaced all the lifters 11,000 miles ago, but I did not know enough to perform the pushrod twist test. I must of got a defective lifter with a bad spring.

Lessoned learned, but I don't mind. I enjoy working on the truck, plus I usually screw things up a few times before getting it right, and then it sticks in my brain.

 

If the lifters are newer then you should also have a look at the pushrod and rocker, problem with either could show up as same symptom

But yes, "they don't make them like they used to" applies to new parts, lol, so most likely it was a defective lifter in that batch of 12

 

Thanks for the recommendation Ron.

I did replace the pushrods at the same time as the lifters, but not the rockers.

So I will now check / replace the rockers too.

 

Just look at the under side to see if its worn down(well up, lol), lifter is usually the issue 99% of the time, but................still that 1% left