Skip to content
View in the app

A better way to browse. Learn more.

Ultimate Subaru Message Board

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

Hydro-lock EA82

Featured Replies

Hi ya

 

Head gasket or bad head?

 

I bought a 90 Loyale with a bad water pump and a recent overheating.

Replaced the water pump then 5 minutes after filling radiator, the combustion chamber of driver’s side cylinder closest to radiator completely fills with coolant requiring removal of spark plug. Isn’t this the first place that would crack when cold coolant is added to an overheated engine? Also the usual…

 

Steam out tailpipe

Coolant flowing out tailpipe after hydro-lock event

Coolant in oil but surprisingly not always

Exhaust gases out radiator

External oil leak from bottom of head gasket, top is dry

No oil in coolant but its not in there long enough to make sure

 

The other three cylinders have no water in them. The other head has no external oil leaks. If I start it right after adding water it will run. Is this a blown head gasket, warped head, cracked head, cracked block, a failed intake manifold gasket or all the above?

 

Im trying to get an idea before or if I take the head off

 

What do yaz think?

This is no blown HG, this is more like a non-existant HG. Usually what happens (and I havent heard of it happening in ages) is putting cold water in an overheated raditor (if you can remove the cap without the 3rd degree burns) and splitting the radiator. Everything is usually so hot that it just becomes steam.

 

It sounds like to me ... and just a guess here.

 

The #1 cylinder hydrolocked with such force it may have stripped the threads for a head bolt. It would fit the external leak, the sudden filling, the ocasional coolant in oil.

  • Author

hi

 

The cylinder was hydrolocked by filling the radiator with water thus preventing the engine from cranking. It did not stall a running engine. Also water had been added to a bone dry overheated engine with a seized, leaky water pump. Replacing the water pump has intensified the blown HG symptoms and added hydrolocking to the list.

Edited by Casino Loyale

Ah okay.

 

Well this goes under the heading ... you can't busticate it any more then it already is.

 

I am going with a crack of some kind as even most HG failures will not loose water that quickly, but a crack of some kind will. A recent overheat and a seized waterpump, I wouldnt even bother with a daignoses and just start with a used engine.

I would suggest bad intake gaskets, as this introduces water into the CC, and will simulate a bad HG less the compression loss.

 

Intake gasets can be deceiving, but at 6 bucks apiece, see if this fixes the matter before it gets worse.

and get them from the dealer, the auto parts chains are die cut from what looks like cereal boxes. they are 5 at autozone, 6 at the dealer. i trust the dealer.

i keep forgetting about those gaskets...

 

i can be a dope at times.

My manifold gasket failed only a few weeks ago. All the same symptoms except exhaust gases in the radiator.

 

I thought it was terminal at the time but it turned out to be a cheap 5min fix.

 

You may also be lucky.

 

Heres hoping

 

IMG_0548.jpg

  • Author

It's been leaking about a quart of oil a week.

Edited by Casino Loyale

 

which one is it?

 

Might be time for you to get the tools out and find out. checking out the manifold gaskets is a 10min job. If they are ok then you know the problem lies further in. But think you will only find out by further exploration.

 

No crystal balls here.

  • Author

Is the #2 cylinder front drivers side? Thats the one filling up

Edited by Casino Loyale

thinking about it, if it were intake gasket leak, BOTH of the cylinders on that side should be filling up with water. pull the head, if it isn't cracked and the block looks good, have both the heads decked at a local machine shop and replace use felpro head gaskets on it (no retorque needed). If the head is cracked between the valves, it can be ok, (subaru released a TSB on this issue) but you would make sure the valves seal to seats, and that the crack doesn't leak from the coolant jacket through the exhaust port or into the cylinder. they can check that at the machine shop. :burnout: good luck

thinking about it, if it were intake gasket leak, BOTH of the cylinders on that side should be filling up with water.

 

I thought about this but it is also possible that the valves are closed on the other cylinder. Maybe turn the engine over 180 degrees and see what happens?

  • Author

hello,

I cranked it, no locking of other cylinder, i smell gasoline in the radiator. so im guessing its a big o' crack to fill it so fast.

Heres hoping its a mullered head gasket.....

 

Time to take the head off and find out.

Please sign in to comment

You will be able to leave a comment after signing in

Sign In Now

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.