Blew engine?

[mobilemedic]

Was driving down the freeway then it started knocking. Had a few choice words and pulled off the road and had my 91 towed home.

This is what it's doing and I an not familiar with what exactly failed with this sound as its not exactly repetitive.

Anyone got an idea and how to physically diagnose?

Thanks. See video I attached below.

https://goo.gl/photos/mgkEF6Wu6RD2ZGrh8

 

[tacosupreme]

Sounds like a rod knock to me. Drop the pan and look for chunkies, I bet there will be a lot of glitter in the oil. Pull the caps on the connecting rods if you don't see something obvious, and have a look at the bearings. My guess is one of them will be mostly missing.

 

[Pin_Head]

It doesn't sound like a rod knock or bad bearing. It does't make noise at idle. You just have to get in there with a listening probe and localize it.

 

[47coeman]

I agree with pin head you can also use a long screw driver placed around to find the noise. Check up top at the valve cover might be lucky and it could be a bent push rod very easy to fix.

 

[LS1FJ40]

I'm with @Pin_Head. Doesn't sound like a rod or bearing. It almost sounds like something is slapping...

 

[grizzlygibbs]

Possibly a drive/belt problem? I would think if it was internal it would not be intermittent.

 

[mobilemedic]

Definitely not a belt. I was thinking it was top end as well. Only concern I had was if pushrod belt, what else gets damaged and I forgot to add that when It bangs it has crap for power. When it died in the freeway bang bang bang and crap power that's when I figured the engine blew.



Is checking a pushrod is a easy as pulling the valve cover? Internals of an engine I've never done. Not afraid.. Done lots of work, just never internal.

Thanks for the help

 

[packetstormin]

Did your truck lose power steering ?

 

[mobilemedic]

No. I'd have cried since I replaced the power steering and Brake booster a month ago No. everything kept. Never died just power loss and bang bang bang from the engine.

 

[jonheld]

That sounds like the fan slapping the shroud to me. Sounds external, but hard to tell across the internets.

 

[thatcabledude]

I know you said the belts were fine so I assume you looked at the pulleys also, but it sounds like a loose wobbling pulley to me. Wouldn't cause a loss in power though.

 

[Comet]

Spark plug? Igniter wire burnt through for me a few weeks back. Lost all power, not just one cylinder.

 

[LS1FJ40]

That sounds like the fan slapping the shroud to me. Sounds external, but hard to tell across the internets.

That's what I thought. If you look at the video the fan looks wobbly. Bearings?

 

[bigfj62]

To me it sounds like plastic hitting. Check fan in the shroud. It starts and stops at certain rpm also. Rod knock or bearing would be mostly constant.

 

[packetstormin]

Pull your fan clutch and start the truck. This rules out the fan.

 

[beachcomberspi]

Sounds external not internal. Look everywhere something could hit-belts, shroud et al. Best wishes.

 

[mobilemedic]

I'll be under the hood later.. I'm positive its in the block somewhere. Hoping it's not a rod but we shall see.

 

[Howard705]

Check all flywheel bellhousing etc also

Sent from my LG-LS970

 

[CRSHR]

Because of the speed of the knock I'm going to say rod bearing as well. Often you won't get a bearing noise until you raise the rpm. Easy thing to do is check the oil for any metal shavings. You can strain some through a coffee filter to help check (I do this a fair amount at work checking fluid condition).


Sent from my iPhone

 

[maxamillion2345]

Definitely not a belt. I was thinking it was top end as well. Only concern I had was if pushrod belt, what else gets damaged and I forgot to add that when It bangs it has crap for power. When it died in the freeway bang bang bang and crap power that's when I figured the engine blew.



Is checking a pushrod is a easy as pulling the valve cover? Internals of an engine I've never done. Not afraid.. Done lots of work, just never internal.

Thanks for the help

On 3fe checking push rods is as easy as pulling valve cover and spinning them in place, yes.