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57L wonbt fire post hydro lock

N

Nermie

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"So,
I've managed to get


"So,
I've managed to get my seized 5.7L turning over after getting water in the cylinders, but she still won't start.
Plugs out and cleaned off the (un-seizing) oil 5x, killed 2 batteries while cranking. She just won’t fire… just some sputtering.

Fuel OK, spark OK,… but no compression.

Compression is very low at 100 and 80 on cylinders 1,3. So, one of three things, I figure:

->Valves (seats)
->Rings
->Timing (hopefully)

TIMING:
I think this engine has a timing chain, located behind the balancer?
How can I easily check to see that valves are opening at exactly correct times? (Valve cover is off.)
Timing just might have jumped a few cogs/links/teeth, so it’s not quite firing right?

(I’ve already checked that plug is firing at APPROX TDC, so rotor cap positions for leads are OK.)

VALVES / RINGS:
Any easy way to check on these w/o taking off head?"
 
"Dont ya just love Hydro Locks

"Dont ya just love Hydro Locks.
A bit more info would be handy, like how did the lock occur and how bad was it.

Your timing chain and sprockets would have to be totaly stuffed and just floping around inside your engine to jump teeth, I have never heard of it happening due to a lock up but that doesnt mean it hasnt happend to someone else.
With valve covers off rotate engine by hand observing valve movement, bring engine up to fire on number 1, both valves should be shut tight, rotate engine 360 degree, as timing marks on crankshaft start to line up, one valve on number 1 will be closing as the other starts to open, (rocking)if this is happening as the marks line up your valve timing is OK.

It sounds a bit like you may have blown a section out of your head gasket between 1 and 3 do your compression test again with all the spark plugs out and note the readings, then screw a plug back into number 3 and retest compression on number 1, if there is an increase in compression reading on number 1 it is starting to point towards the gasket
This can be confirmed by doing a leakage test using compressed air, adapt an air fitting to screw into your spark plug hole, make sure you are on compression stroke on number 1 (valves closed coming up to fire ) flow compressed air into number 1 cylinder (at low pressure) with the spark plug removed from number 3 and see if you are getting a stream of air out through the spark plug hole, if so the gasket is shot.

You can check for ring wear/damage by squirting a bit of oil into each cylinder as you re check compression readings and look for a significant increase in reading when you do this compared to your original readings, a big difference points to rings.

You can check valves using the leakage test, check each cylinder individualy on compression stroke, (valves closed comming up for fire) using the compressed air in through the fitting into the plug hole, observe for air flowing out at inlet manifold/carby air horn, or out the exaust, indicating a problem with the inlet or exaust valves.

There is a bit there to take in, I hope it helps but I would have to say with just 2 cylinders low on compression I would still expect it to start but just to run very rough, you may well have some fuel or ignition issues as well.

Good Luck
Cheers
Peter C"
 
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