4.0 OHV noise

fordrangerforumuser · Oct 2, 2018

Okay started truck in the morning to circulate coolant before I flush it to change radiator. Forgot about it. Got back from lunch and trucks making a weird noise. Not overheating but probably got hot for a few minutes (radiator is bad coolant system gets air trapped in it).

Noise partially goes away when I press the clutch, don't think its the pilot bearing although that may be some of it. Oil looks fine, sounds like its coming from the engine, only notice it at idle and low revs when I touch the gas. Doesn't sound like any lifter or rod bearing i've heard, not very consistent.

Only thing I can come up with at the moment is timing chain tensioner/guides? Unknown miles on the motor.

https://www.youtube.com/watch?v=-o6Xcj8Z6T0&

Denisefwd93 · Oct 2, 2018

Get underneath see if your catalytic converter is rattling

RonD · Oct 2, 2018

When engine is COLD loosen fan belt and remove it from crank pulley, then start the engine
See if you hear the noise, if not then noise is from one of the fan belt pulleys, check them.

DO NOT FORGET about it this time, you should only run COLD engine without water pump for 2 minutes.

Also with fan belt off, engine bay will be VERY QUIET, no fan noise, so if you still hear the noise it might be easier to pin point

fordrangerforumuser · Oct 2, 2018

RonD said:
When engine is COLD loosen fan belt and remove it from crank pulley, then start the engine
See if you hear the noise, if not then noise is from one of the fan belt pulleys, check them.

DO NOT FORGET about it this time, you should only run COLD engine without water pump for 2 minutes.

Also with fan belt off, engine bay will be VERY QUIET, no fan noise, so if you still hear the noise it might be easier to pin point

I’ve never heard a bad tensioner sound like this. Usually just the bearing destroys itself. I’ve got it got quite a few times but doesn’t show signs of head gasket failure. Noise goes away with rpm so I’m stumped with this one.

Denisefwd93 · Oct 2, 2018

Ron's advice is quite good, suggest you try it. Video is good but not that good it sounds like the catalytic converter to me.

fordrangerforumuser · Oct 2, 2018

Denisefwd93 said:
Ron's advice is quite good, suggest you try it. Video is good but not that good it sounds like the catalytic converter to me.

There’s no cat on the truck it’s internal or transmission

fastpakr · Oct 2, 2018

Why is there no cat?

fordrangerforumuser · Oct 2, 2018

The exhaust was trashed when I took it out to put a new trans in and I made the cheapest exhaust possible

AdirondackRanger · Oct 3, 2018

oh boy.. that don't sound good at all.. Looks like lots of low rpm vibration going on

AdirondackRanger · Oct 3, 2018

input shaft bearing? Isn't pilot bearing noise more of a constant noise if it goes bad?

fordrangerforumuser · Oct 3, 2018

AdirondackRanger said:
input shaft bearing? Isn't pilot bearing noise more of a constant noise if it goes bad?

I thought that but driving it shifting gears makes no difference. Gonna pull the timing cover when I pull the rad hopefully find something. It’s had a lifter or rod knock for a second at startup after sitting since I got it but this doesn’t sound like that at all.

RonD · Oct 4, 2018

fordrangerforumuser said:
I thought that but driving it shifting gears makes no difference. Gonna pull the timing cover when I pull the rad hopefully find something. It’s had a lifter or rod knock for a second at startup after sitting since I got it but this doesn’t sound like that at all.

On cold start you can use "Clear Flooded Engine" routine to get oil circulated before startup
I use this every morning on my high mile 4.0l engine

Turn key on
Press gas pedal down to the floor and HOLD IT DOWN all the way
(when computer "sees" Full Throttle/WOT, and 0 RPMs it turns OFF fuel injectors)
You are now in "Clear Flooded Engine" routine

Now crank the engine, it should not start or fire, no fuel
After 5-10 second or so release gas pedal and computer will start fuel injectors, and no Knock noise on startup

If engine starts with gas pedal to the floor then your throttle cable has stretched, so you no longer have WOT.
Google: Ranger throttle cable mod

Simple, cheap and effective fix, you will be surprised on how much more power you have now

fordrangerforumuser · Oct 6, 2018

Pulled calve covers d timing cover and unfortunately found nothing so i guess it busted a piston skirt when it got hot idling. Gonna throw it all back together with some 15w-40 hopefully get me by for a bit.

Denisefwd93 · Oct 6, 2018

fordrangerforumuser said:
Pulled calve covers d timing cover and unfortunately found nothing so i guess it busted a piston skirt when it got hot idling. Gonna throw it all back together with some 15w-40 hopefully get me by for a bit.

Didn't take the belt off per Ron's advice?

fordrangerforumuser · Oct 6, 2018

Denisefwd93 said:
Didn't take the belt off per Ron's advice?

No, I pulled the timing cover without taking the belt or any accessories off.

I think I've isolated the noise to the transmission. I've had a whine in gears 1-3 and 5-R for a while now progressively getting worse (thought it was just louder because I took out my carpet.)

If I turn the crank back and forth by hand in neutral or 1-3 5-r I get a loud clunking noise. I do not get that noise in 4th. 4th gear should lock the input and output shafts together which would explain the noise, and all the metal shaving on the trans plug. Fluid was dark, engine oil looked good minus some water from when I pulled the timing cover.

Hopefully I still have a warranty on the transmission, not looking forward to swapping it out again but at least its light enough to manhandle.

4.0 OHV noise

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