Something Broken In The Head

DomMc · Nov 1, 2015

Found this piece just lying in the corner when I took the cover off the top of the passenger side.

Since there is a groove am guessing its part of the mechanism that holds the push rods...
am starting to wonder if this car did 'run when parked' after all...

Am going to take as much of the engine out today to see if I can see why it's seized.
Finding pieces hasn't boosted my confidence though.
I cant see anything that looks broken though. Thats the weird part.

DomMc · Nov 1, 2015

Update to the above - I got the head off both sides and things dont look good.
Two of the pistons are at the same height, which with my basic knowledge of engines, seems very wrong.

Can anyone confirm?

Adieu · Nov 1, 2015

DomMc said:
Update to the above - I got the head off both sides and things dont look good.
Two of the pistons are at the same height, which with my basic knowledge of engines, seems very wrong.

Can anyone confirm?

In most engines, 2 pistons will be at or near TDC at the same time, one will be on the intake stroke, the other on the exhaust. It's why when doing valve adjustments on a "Vee" engine, you can do one valve each on two cylinders at a time if you know what you're doing, or just do it the slower, but easier to keep track of one-at-a-time like I do.

DomMc · Nov 2, 2015

74stang2togo said:
In most engines, 2 pistons will be at or near TDC at the same time

Would it right to say that there should be symmetry between both side of the engine though?
I've tried to show how they look at present.

View attachment 544302

Perhaps this is an acceptable position for all. (Hopefully!!!!!)

DomMc · Nov 2, 2015

74stang2togo said:
In most engines, 2 pistons will be at or near TDC at the same time

Would it be right to say that there should be symmetry between both sides of the engine though?
I've tried to show how they look at present.

Perhaps this is an acceptable position for all. (Hopefully!!!!!)

Adieu · Nov 2, 2015

Firing order has a lot to do with it. Remember, each piston hits TDC twice in one complete combustion cycle, once on the compression stroke, and once on the exhaust stroke.

If the engine's locked up and won't turn over by hand, you'll need to remove the oil pan and look at the bottom of the engine for a broken crank or bent or broken connecting rod.

Totally different engine family (Ford/Nissan 3.3 from a Quest/Villager), but notice how it's similar?

Same here on a Chevy small-block. (Kind of having to go with what I can find, have filtered internet here at work so Photobucket and a few other of my usual sources are ruled out.)

DomMc · Nov 2, 2015

I read that removing the oil pan is possible with the engine still in the car?
But if something is broken, which I think we can assume is the case... the engine would need to be lifted out to repair, right?

So really, I should probably just plan to pull the engine regardless?
or is there a chance this can be repaired without pulling the engine...

Adieu · Nov 2, 2015

DomMc said:
I read that removing the oil pan is possible with the engine still in the car?
But if something is broken, which I think we can assume is the case... the engine would need to be lifted out to repair, right?

So really, I should probably just plan to pull the engine regardless?
or is there a chance this can be repaired without pulling the engine...

You can pull the pan and get a look inside with it in the car, but any kind of bottom-end repair is going to be nearly impossible with it in the car.

DomMc · Nov 2, 2015

Great, thanks,
I've pretty much resigned myself to having to pull the engine at this stage... just hadn't budgeted for it.! - and had thought that the car would come back to life without getting this deep in to it.
But hey, where would the fun be in that, right!?

LILCBRA · Nov 2, 2015

Is it metal or something like old rubber? I was wondering if it might just be a piece of dry rotted/old valve seal?

DomMc · Nov 2, 2015

LILCBRA said:
Is it metal or something like old rubber? I was wondering if it might just be a piece of dry rotted/old valve seal?

It's solid (definitely not rubber) but very light.
It looks to the valve train material but I can't see any damage anywhere.

LILCBRA · Nov 2, 2015

Well......

Since you have the heads off the car now, you could get yourself a valve spring compressor and disassemble the heads? I´m sure you would benefit from changing the valve seals at very least and hopefully confirm that your heads are good at the same time. Some of the work depends on how mechanical you are, but removing/replacing valves isn´t hard and I think most people could do it the first try if instructed.

jozsefsz · Nov 2, 2015

Looks like crumbled up valve stem seal to me. Especially from where you found it.

Personally I've never seen an engine fail with a piston just sitting there, not without a connecting rod sticking out of the side of the pan. If you do pull the pan with the engine in-car, please let us know how that goes. I've got a few dents on mine and am reluctant to pull the whole engine if I don't have to.

If you're concerned about valvetrain binding, just remove the whole shaft on both sides. 3 bolts and it's out.

By the way, have you gotten around to checking the timing gears? That is absolutely the most common source of problems in these engines. Guaranteed to fail and very possibly locking up the engine when it does.

DomMc · Nov 2, 2015

I've pulled both valve trains and they seemed fine... not locked up or anything.
And there was a semblance of oil around so that's probably a good sign.

Got the timing cover off on Friday and again, things seem ok in there.
I pulled the bolt from the top gear, and was able to jiggle the gear back and forth a small amount.
Seems like its the crank thats locking things up.

When you say fail? I guess you mean the teeth break and lock up the gears or something? All looked ok from what I can see.

jozsefsz · Nov 2, 2015

Cool, that looks pretty aok to me. It also looks like it already got the aftermarket steel cam gear. The originals were plastic believe-it-or-not, and they'd frequently crumble and jam up the gears.

Brighter side you've got this thing most of the way apart for a rebuild. I agree that next up will be pulling the pan to see what you have going on down there. Before you do, with the heads off, you could try whacking each piston head with a soft mallet to see if you can get the problem child to free up. It's gotta move one way or another!

84Ttop · Nov 2, 2015

If the motor is "locked up" I would plan on removing it to be gone through. It's likely that it won't last long or be in great running condition even after free'd up

jozsefsz · Nov 2, 2015

84Ttop said:
If the motor is "locked up" I would plan on removing it to be gone through. It's likely that it won't last long or be in great running condition even after free'd up

I'd ordinarily agree with you, except that I have the same engine (2.8 v6) in my II, and it was locked up when I got it. Some persuasion with an impact wrench after some WD-40 soaking and it's been running like a top for two years. Something about those engines liking to seize while sitting, but they're pretty bullet-proof otherwise. If of course the Op doesn't have some mechanical damage, in my case it was just a bit of corrosion keeping things from moving.

Adieu · Nov 2, 2015

jozsefsz said:
I'd ordinarily agree with you, except that I have the same engine (2.8 v6) in my II, and it was locked up when I got it. Some persuasion with an impact wrench after some WD-40 soaking and it's been running like a top for two years. Something about those engines liking to seize while sitting, but they're pretty bullet-proof otherwise. If of course the Op doesn't have some mechanical damage, in my case it was just a bit of corrosion keeping things from moving.

What can happen, and could be happening here (and was likely what happened in your case) is a bit of light rust keeping the rings from moving in the bores, which keeps the piston from moving and so on. It happens at times when an engine is left sitting for long periods of time in a high humidity environment. In that case, the cure would be an oil change, and to soak all six bores in some form of penetrating oil (the aforementioned WD40 works well) for a day or so, allowing the oil to seep down into the rings, penetrate the surface of the metals involved, and loosen things up. After that, and attempt can be made at turning the engine over by hand. This is all IF pulling the oil pan doesn't reveal carnage, I'd still recommend that as a first step for a locked up engine simply to make sure you're not going to damage anything further if there is existing damage.

DomMc · Nov 2, 2015

74stang2togo said:
.... an engine is left sitting for long periods of time in a high humidity environment...

Car bought in Texas, and had been sitting in the sun since 2008.
Hmmmm....

DomMc · Nov 10, 2015

Any tips on pulling the engine?
I got a universal lift plate from autozone but it doesn't even remotely fit.
Can drill it out to match the carb bolts but was hoping you guys could provide some wisdom!

Something Broken In The Head

DomMc

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DomMc

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Adieu

Easy there, this ain't a dating site.

DomMc

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DomMc

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Adieu

Easy there, this ain't a dating site.

DomMc

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Adieu

Easy there, this ain't a dating site.

DomMc

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LILCBRA

I wish I didn't have all of these balls in the air

DomMc

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LILCBRA

I wish I didn't have all of these balls in the air

jozsefsz

DomMc

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jozsefsz

84Ttop

They make new pistons every day, so why worry?

jozsefsz

Adieu

Easy there, this ain't a dating site.

DomMc

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Something Broken In The Head

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I wish I didn't have all of these balls in the air

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They make new pistons every day, so why worry?

Easy there, this ain't a dating site.

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