1993 Ford Explorer Sport Ticking or Knocking?

[93SportExplorer]

Does this sound like a top end tick or a lower knock? I've owned this for the last 12 years and 55k miles, (now roughly 160K on the Odo) and have never been very good at routine oil changes. This sound used to go away after warm-up but it's been sitting for a year or so and now seems to be permanent. I tried a mechanics stethoscope on the valve covers and oil pan but it kinds sounds the same everywhere. I've done a fair amount of research on this forum but I don't have enough experience to know what i'm hearing.

https://www.youtube.com/watch?v=x5Np69Gt4Yw

Thoughts?

 

[Turdle]

Video is set to private.

 

[93SportExplorer]

Thanks. fixed.

 

[natenkiki2004]

I know a valvetrain tick when I hear one... that's not valvetrain

Here's mine making valvetrain noise, you can hear it towards the end:
https://www.youtube.com/watch?v=5LLOIC2KniY

Notice it's higher pitched and comes & goes as the hydraulic lifters fill up and then lose oil pressure (partially clogged). Your noise is much lower & deeper and consistent.

I really hope I'm wrong though, for your sake.

 

[FR-425]

That's rod knock or possibly a cracked flex plate.

OR harmonic balancer, loose accessory bracket, etc.

 

[93SportExplorer]

Well I don't think that's what I wanted to hear. Rod knock, just roll it off a cliff or?

 

[natenkiki2004]

Or... pull the engine. Very difficult to get the oil pan off in these vehicles and even if you did, you'd be doing rod bearings on your back on the ground. To do it 'right' would be to do an engine rebuild.

If the vehicle itself is nice with a good trans, you could find an engine at a junkyard easily and swap it in. Many of our Explorers died due to transfer case & transmission problems, not usually engine problems.

 

[2stroke]

It sounds like rod knock to me. You can either fill it with 20w50 oil and drive it until it throws the rod out the block, or replace the engine. That sounds pretty bad to me, I doubt it will last much longer. Its probably too late to be worth a rebuild. If it was me, I would get a junkyard engine and replace it.

 

[93SportExplorer]

What causes rod knock like this? Seems odd to have failure of this type on this motor at 160K. I keep hearing of guys running the early explorers 200 & 300K.

Thanks for all the info.

 

[natenkiki2004]

Lack of oil changes or running the oil too low or wrong viscosity. These engines are rock solid, if maintained. Maintenance is key.

IMO, do what 2-stroke said. I don't know that I'd jump straight to 20w-50, maybe try Rotella 15w-40 first. If it quiets things down, run with it. I just wouldn't trust it for long-haul trips or daily driver critical use.

Start looking for a 4.0L OHV off a wrecked car or one with transmission issues; 1991-2000 Explorer (I'd prefer a 1993/1994), similar years for Ranger, don't bother with an Aerostar. Skip the SOHC, even if the bolt patterns line up. Once you have a 4.0L, go through it and do quite a few gaskets like front & rear main seals, oil pan, timing cover, water pump. Strip everything off above the lower intake manifold (sensors, upper intake, etc) and bolt all your goodies to it. Drop it in & cross your fingers.

 

[FR-425]

Double check to be sure you don't have a broken bracket. a/c, power steering, alternator, etc. A busted bracket banging against the block can sound like a knock.

I would also get underneath with the engine running and listen to see if the sound is coming from the bell-housing area. It may be a cracked flex plate. (more common than rod knock on this engine)

 

[93SportExplorer]

Ok, I'll check those things out. Broken bracket should be obvious by grabbing and trying to wiggle by hand correct? Flex plate issue will manifest louder knock with Mechanics stethoscope on bell housing than on oil pan?

 

[2stroke]

Yes, there is nobody that can say with certainty what that sound is over the internet. You have to be there in person, and it should be fairly obvious when crawling under the vehicle.

 

[EastoutWest]

Here's mine making valvetrain noise, you can hear it towards the end:
https://www.youtube.com/watch?v=5LLOIC2KniY

Notice it's higher pitched and comes & goes as the hydraulic lifters fill up and then lose oil pressure (partially clogged).

I really hope I'm wrong though, for your sake.

Mine sounds the same, intermittent valvetrain ticking. I never knew why! Partially clogged lifters... have you been able to correct it? Engine flushing? Or it can't really be corrected without a rebuild...?

 

[2stroke]

I have heard its possible to clean the lifters, but its hard to get all the gunk. I figure if you pull the head apart, you might as well put in new lifters. A better solution is to just live with it. Our 2000 has been doing it for almost 100k miles and its close to 200k miles now.

 

[natenkiki2004]

I have heard its possible to clean the lifters, but its hard to get all the gunk. I figure if you pull the head apart, you might as well put in new lifters. A better solution is to just live with it. Our 2000 has been doing it for almost 100k miles and its close to 200k miles now.

Bingo. You can't fully clean the lifters without taking them out which means taking the heads off. If you go to that much trouble and cost, just put new lifters in (though that begs the question of needing a new cam...).

My theory is... the oil stops at the lifters, excess pressure is bled off but the oil can't leave the lifter. Because the oil isn't flowing through the lifter, it can't get cleaned out and debris/crud settles in there. Seafoam likely won't help, at least not in the ratio that would still allow your oil to be a lubricant.

I'm living with my tick. Sometimes it's bad enough to cause the engine to shake 2-3 seconds while it's trying to breathe (I'm sure the connecting rods LOVE that). But really, I'm not digging that deep until a head or head gasket blows. Even then, the cost of doing things right, I might just swap in a used long block or something.

Anyway, this is all off-topic. OP, have you listened/hunted around for the source of your sound?