FG Falcon ate water. What to do now?

[XF EDDIE 165]

3 days ago I learned the meaning of if its flooded forget it and my fg falcon got the engine flooded with water. I pulled the plugs out and got the water out of the cylenders but it wont run now and the engine sounds very lumpy. Im planning on running a compression test but what kinda damage am I gonna be in for. Im already suspecting bent con rods or bent valves but I dont know how to check that apart from just pulling the head and looking at it. Any help would be much appreciated!

[deankxf 20,904]

bent con rods are likely. 

there might be a way to check by dipping something down the spark plug holes and rotating the engine by hand.
if one or 2 are lower on each top of the stroke position  then bent conrod is confirmed. 

 

[XF EDDIE 165]

Ill give that a try. If con rods are fked what else needs doing or could I get some rods and go?

[deankxf 20,904]

55 minutes ago, XF EDDIE said:

Ill give that a try. If con rods are fked what else needs doing or could I get some rods and go?

depends i guess. 

if it was mine i'd probably chuck another engine in. 

@Thom may know if a bore could crack from it, i'd expect it possible, so therefore having the engine block crack tested might be something to do. 
i wouldn't expect anything else, but i also don't know heaps about this issue. 

[XF EDDIE 165]

1 hour ago, deankxf said:

depends i guess. 

if it was mine i'd probably chuck another engine in. 

@Thom may know if a bore could crack from it, i'd expect it possible, so therefore having the engine block crack tested might be something to do. 
i wouldn't expect anything else, but i also don't know heaps about this issue. 

That probably would be the go, although if most of the guts are ok I was maybe thinking of doing a turbo build (nothing too crazy just put some stock xr6t parts on it if i can find them cheap)

[SPArKy_Dave 9,295]

7 hours ago, XF EDDIE said:

3 days ago I learned the meaning of if its flooded forget it and my fg falcon got the engine flooded with water.

 

How did that happen - a flooded road?

 

Yeah, water doesn't compress,

although I wouldn't have thought bent conrods, would make the engine run poorly?

 

An inspection camera down each bore, could be helpful maybe?

A leakdown test, would show any bent valves.

Plus as @deankxf says, measuring each cylinder stroke with a plastic stick or similar, would be useful!

 

Did you replace the oil too - I imagine that would be full of water also?

 

[XF EDDIE 165]

42 minutes ago, SPArKy_Dave said:

 

How did that happen - a flooded road?

 

Yeah, water doesn't compress,

although I wouldn't have thought bent conrods, would make the engine run poorly?

 

An inspection camera down each bore, could be helpful maybe?

A leakdown test, would show any bent valves.

Plus as @deankxf says, measuring each cylinder stroke with a plastic stick or similar, would be useful!

 

Did you replace the oil too - I imagine that would be full of water also?

 

The oil has no water in it as I got to the other side before it died. Yeah flooded road with overgrown depth markers, water was only about 30 cm deep but this car is too low for almost any water and so it went over the bonnet and flooded the intake. Im worried if maybe the main bearing caps would have been damaged, if the block and head are salvagable ill put some new rods in it and do it up to xr6t spec. Also might be a dumb question but would el rods fit? I got an el bottom end in the scrap heap and it would be nice to get something out of it

[Thom 6,707]

depends i guess. 
if it was mine i'd probably chuck another engine in. 
[mention=43]Thom[/mention] may know if a bore could crack from it, i'd expect it possible, so therefore having the engine block crack tested might be something to do. 
i wouldn't expect anything else, but i also don't know heaps about this issue. 

The oil has no water in it as I got to the other side before it died. Yeah flooded road with overgrown depth markers, water was only about 30 cm deep but this car is too low for almost any water and so it went over the bonnet and flooded the intake. Im worried if maybe the main bearing caps would have been damaged, if the block and head are salvagable ill put some new rods in it and do it up to xr6t spec. Also might be a dumb question but would el rods fit? I got an el bottom end in the scrap heap and it would be nice to get something out of it

Compression test will show if the engine is mechanically damaged, all cylinders within 5-8% of the same reading should still run smoothly, a bent rod or valves will show lower compression on that cylinder, cylinder walls can crack from hydrolocking but you would most likely bend rods firts (and possibly damaged the skirt on a few pistons if the rod hes bent far enough to let the piston hit the crank, alternatively if the rod twisted it could have bent far enough the valve reliefs dont line up any more, in that case you would have bent valves too) and if the cylinder wall was cracked you would have water in the sump, main bearings will be totally fine unless you've managed to bend the crank but it would probably not run if you managed to do that, e series rods are shorter than au-fgx except el hybrid engines they are the same length as au-fgx, the bigger problem for swapping rods on anything but a factory turbo 4.0 is they use a press fit gudgeon pin and are quite difficult to change without the proper equipment,.you also can't put sohc pistons in a barra as the valve reliefs are in the wrong position for the barra head

[XF EDDIE 165]

40 minutes ago, Thom said:

Compression test will show if the engine is mechanically damaged, all cylinders within 5-8% of the same reading should still run smoothly, a bent rod or valves will show lower compression on that cylinder, cylinder walls can crack from hydrolocking but you would most likely bend rods firts (and possibly damaged the skirt on a few pistons if the rod hes bent far enough to let the piston hit the crank, alternatively if the rod twisted it could have bent far enough the valve reliefs dont line up any more, in that case you would have bent valves too) and if the cylinder wall was cracked you would have water in the sump, main bearings will be totally fine unless you've managed to bend the crank but it would probably not run if you managed to do that, e series rods are shorter than au-fgx except el hybrid engines they are the same length as au-fgx, the bigger problem for swapping rods on anything but a factory turbo 4.0 is they use a press fit gudgeon pin and are quite difficult to change without the proper equipment,.you also can't put sohc pistons in a barra as the valve reliefs are in the wrong position for the barra head

The engine dosent sound too fucked up (no knocking or scraping) just sounds like it has a dead battery. So if the rods are bent could I still run a leakdown test to see if the valves are still good? Im just thinking if just the rods are bent can I just get some used rods and just slap it back together?

[Thom 6,707]

The engine dosent sound too fucked up (no knocking or scraping) just sounds like it has a dead battery. So if the rods are bent could I still run a leakdown test to see if the valves are still good? Im just thinking if just the rods are bent can I just get some used rods and just slap it back together?

If its winding over slow that's a good indication of bent things, unfortunately you won't know what you need to replace until you do a bit more investigation, a leak down test will show if the cylinders are still sealing, but if you've got to pull the head off anyway to change rods+ whatever else is damaged you may as well inspect the valvetrain while it's off

[SPArKy_Dave 9,295]

Does the compression sound even, when cranking (even slowly?)

Does it crank faster, with the spark plugs out?

 

The starter could be shorting internally, due to to water ingress?

I'd try measuring the current draw, if you have a clamp style ammeter.

[XF EDDIE 165]

Well ive done a compression test and everything is bad. First off the tips of the plugs were all wet with water so there have been more water hiding in the intake and second the readings arent great with all cylinders being zero except for for number 1 which was 30. I could hear compression when I put the gauge in and this gauge has been very dodgy before so im going to rerun the test with a new gauge. However if these readings are correct what does this mean? Bent valves across the board?

[the miracle stick mechanic 89]

11 hours ago, XF EDDIE said:

Well ive done a compression test and everything is bad. First off the tips of the plugs were all wet with water so there have been more water hiding in the intake and second the readings arent great with all cylinders being zero except for for number 1 which was 30. I could hear compression when I put the gauge in and this gauge has been very dodgy before so im going to rerun the test with a new gauge. However if these readings are correct what does this mean? Bent valves across the board?

Is it auto or manual transmission ?

If auto, the torque converter would slip before the engine is bending the conrods.

Did the rear wheels skid when it happened ? 

[Thom 6,707]

Well ive done a compression test and everything is bad. First off the tips of the plugs were all wet with water so there have been more water hiding in the intake and second the readings arent great with all cylinders being zero except for for number 1 which was 30. I could hear compression when I put the gauge in and this gauge has been very dodgy before so im going to rerun the test with a new gauge. However if these readings are correct what does this mean? Bent valves across the board?

Sounds like it's autopsy time, if the gauge is correct, it means that every cylinder has damage, you won't know without pulling the head off or using a bore scope to assess what went wrong, but if I were a betting man I would say you have more than your fair share of bent rods and valves, and if it is really that bad you may be better of financially to just swap the whole engine

[the miracle stick mechanic 89]

19 hours ago, Thom said:

 

 

Sounds like it's autopsy time, if the gauge is correct, it means that every cylinder has damage, you won't know without pulling the head off or using a bore scope to assess what went wrong, but if I were a betting man I would say you have more than your fair share of bent rods and valves, and if it is really that bad you may be better of financially to just swap the whole engine

 

How exactly does water in the engine bend a valve when it would just pump the water through an open valve ?

He hasn't even done a compression test with a decent compression gauge .

I disagree .

 

[Thom 6,707]

How exactly does water in the engine bend a valve when it would just pump the water through an open valve ?
He hasn't even done a compression test with a decent compression gauge .
I disagree .
 

Rod bends and twists, valve pocket is no longer below valve, flat of the piston hits a valve and bends it

[XF EDDIE 165]

Just wondering what engines can I put in a fg? I saw a bf barra come up for cheap near me and was wondering if it would work?

[deankxf 20,904]

1 hour ago, XF EDDIE said:

Just wondering what engines can I put in a fg? I saw a bf barra come up for cheap near me and was wondering if it would work?

in case no one else jumps in before you find the answer. 

i believe the dipstick location could be an issue, (block or sump may need drilling) sump and might be different,  
definitely look it up before buying. (i only vaguely remember Street Machine's turbo taxi being a pain for similar reasons. )

[XF EDDIE 165]

17 hours ago, deankxf said:

in case no one else jumps in before you find the answer. 

i believe the dipstick location could be an issue, (block or sump may need drilling) sump and might be different,  
definitely look it up before buying. (i only vaguely remember Street Machine's turbo taxi being a pain for similar reasons. )

Ahh great

[XF EDDIE 165]

Ok so Ive got my new compression tester and got some new results

Cylinder 1: 90 psi

Cylinder 2: 90 psi

Cylinder 3: 50 psi

Cylinder 4: 55 psi

Cylinder 5: 30 psi

Cylinder 6: 25 psi

I'm thinking bent con rods at this point but I'll do a leak down test before I start the autopsy. Got any other thoughts on what I should do before I crack the head off?

[SPArKy_Dave 9,295]

1 hour ago, XF EDDIE said:

Got any other thoughts on what I should do before I crack the head off?

 

I'd check for bent conrods, using a straw, plastic stick or similar, down the spark plug holes.

[Thom 6,707]

Ok so Ive got my new compression tester and got some new results
Cylinder 1: 90 psi
Cylinder 2: 90 psi
Cylinder 3: 50 psi
Cylinder 4: 55 psi
Cylinder 5: 30 psi
Cylinder 6: 25 psi
I'm thinking bent con rods at this point but I'll do a leak down test before I start the autopsy. Got any other thoughts on what I should do before I crack the head off?

You may as well just pull it apart, with that much variation it's not going to be fixed without at least the head coming off so you'd as well do it to know what your up against

[deankxf 20,904]

4 hours ago, Thom said:

 

 

You may as well just pull it apart, with that much variation it's not going to be fixed without at least the head coming off so you'd as well do it to know what your up against

 

 

that's what i was going to say, 

surely with 100psi lost in each cyl, it's got some serious issues..
taking the rocker cover off might show some gnarly carnage alone.