'88 GT Convertible - Croatia, Europe

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snovak

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Oct 9, 2020
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The oil pressure is good?
The crank end play is now good
Short out spark one cylinder at a time and try to isolate knock
Pull the heads off
By the looks of those bearings it may have a loose piston
Real hard to inspect pistons and wrist pins with them still in the block
Mechanical gauge oil pressure after cranking 50psi, 70-80 when I rev it a bit... allthru with knock coming out I am affraid to...
Crank play is perfect now, lower (0.004") factory specification.
I was shorting our plugs several times, only time when there was a change is when I pulled BOTH #5 and #1. Knock went away.
Right there, on first main journal I felt with the finger a very very slight embossed middle of the journal, right where oil passage is. So not groove, but like that part of the journal is rised.

I am not trained mechanic, but engine and journals didn't look bad to me. Bearings were gone, all of them, and that was obvious since I took the cap off.
G** damn, I am closer and closer to pulling the engine for rebuild, this is nerve and time consuming.... but first to confirm 100% change exhaust gasket ans check flexplate....

Are thoose Sealed Power and Enginetech piston and rings from Rockauto any good? I don't want to risk, first sign of wear and I am also changing pistons...

Wrist pin.
That means pulling and tearing the engine down..
Wrist pin would make piston up/down movement lash? Is there any way to confirm 100%? I don't know.... like boroscope camera or wooden stick thu spark plug hole and turning the crank left-right when having a cylinder on TDC?

Right now, I have a condition being affraid of having the same knock after nice shinny rebuild.
I changed water pump, clutch, chain and sprockets, harmonic balancer (THERE ISSUES STARTED WITH HB), lifters, pushrods, rockers, rocker bolts, injectors, and now oil pump, oil pickup, all bottom bearings and I still have a damn knock... as a matter of the fact I have only pistons and camshaft left, or crankshaft (which I could not measure went south)...

Eitherway, thnx for your support up to this point!
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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If knock was from crank bearings it would be audibly less now even if the crank was bad.
 
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90sickfox

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That sounds a lot like the spacer plate rubbing the flywheel in the video. The plate between the engine and transmission. Almost a scraping noise. It could be just the way the audio picked it up.
 
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snovak

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@90sickfox I wish so, but don't You think it would hardly travel thru crankshaft up to oil filter, driver side lower timing cover to block bolts...? Would it?
Eitherway, inspection cover is off, I will re-check again. Thnx.
I also plan to disconnect engine and AOD and check situation around flexplate to crank bolts....maybe run the engine without tranny...

With checking the flexplate and exhaust manifold gasket I am out of options and rebuild is next logical step... :-(
 

90sickfox

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Listen to the timing cover behind water pump. If noise is there it could be the camshaft bolt has come loose or the oil slinger is hitting cover. The flywheel usually won't make noise travel to the front of engine.

Noise that loud should've given definite evidence of where it is. I'd expect bearings or pistons to be completely torn up making that type of noise. Video audio can be deceiving though.
 

snovak

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@90sickfox and @General karthief You may be right afterall...
It's pretty tight there between flexplate and block plate (and I don't know there really boroscope went) but I clearly see aluminium scraping, and particles of plate when pulling boroscope out (third picture)...

Althru I need to separate engine and tranny, if this is what knock was, it would be a rise from the ashes for this fox and me...

Still need to confirm, but... how did that happen?
Clogged tranny cooling lines?
(I have had thrust bearing failure, latest leaks at coolinf line-to-aod fittings, and noticed tranny tunnel warm on last few rides which I assumed was from hot weather back then...)
Did I mess up changing engine and tranny mounts? The old ones were shot... so new ones may had raised engine/tranny if it matters...
 

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90sickfox

Wasn't a pretty sight...and I've got big hands
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There really isn't anything that will cause the block plate to move. Im guessing heatvcoukd make it warp a little but shouldn't be enough to touch the flexplate. I've seen flex plates crack though just from use over the years. Doesn't happen as much on ford's but chevys do it all the time.

There's also a piece the sits at the bottom at the front of the bell housing. If something hit and bent it there it can cause it to rub.

I hope this is the only problem and you'll be back to driving around soon. Atleast now you've added a bunch of time to your engine with the new bearings. They were really about to destroy something.

Sometimes my car will lead me down the fix this and fix that path. I think it's just leading me to other things that would've been a big issue if I hadn't found them when I did. Without the knock you wouldn't have done your bearings. Your car is just making you think on your toes.
 
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snovak

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Update... I was having 'fun' putting back the front springs in their place (in order to stay alive, I used backside method with lowering LCA bushings towards engine with 100% success).
I still have some (maybe stupid) belief that the knock is outside of the engine. My goal is to separate aod from engine and start it without tranny before pulling the engine for rebuild.


Today I took out the flexplate to converter bolts and as soon as I took them out saw some (at least) 1/4" play between flexplate/crank and converter (see pictures).
All four holes are oval and when turning the crank You can hear knock. The bolts were tight, one of them much more than others, but all of them are shiny at the back....
Is this normal or may I have some issues with flexplate/converter?
 

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snovak

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Got it apart.
Okay guys, help: what is this? Flexplate to crank bolts pressed into converter face?
 

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manicmechanic007

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There is an old TSB for that
I think they were just putting washers between the converter and flex plate to begin with and had updated parts after that
Machine or grind down the heads of those flexplate bolts and that should do you
You could get technical and make them all weigh the same or buy some with not as thick a head
 
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manicmechanic007

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That is why they call it a flex plate
Early E4OD in trucks was so bad it punched holes in a few converters and made them leak fluid
 
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snovak

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That is why they call it a flex plate
Early E4OD in trucks was so bad it punched holes in a few converters and made them leak fluid
Thnx. Yap, got that part "flex"-plate but as I chase knock source after crank play fix I automatically saw this as a potential pushing of the crank too much forward or converter balooning or whatever...
By Your reaction this may be normal...
 

manicmechanic007

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Put it back together and retest it after new or modified bolts
They knock real bad with those bolts contacting the converter
 

manicmechanic007

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Not normal if they are knocking
Normal in the sense that they are so close that there are often witness marks where the bolts were
If they do not knock the marks are normal
 
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