Is my motor hydro-locked?
#21
Senior Member
Certified GM nut
![Default](https://www.gmforum.com/images/icons/icon1.gif)
Too far. You shouldn't need to remove the heads. Once you take off the black UIM, you'll see the metal LIM below that. The LIM gaskets in question are directly underneath that. That'* as deep as you need to go for this repair.
#22
Senior Member
Posts like a 4 Banger
Thread Starter
![Default](https://www.gmforum.com/images/icons/icon1.gif)
ok so if i dont have to remove the heads, do i do the cranking after i reinstall everything to remove the fluids? because my setup has the Upper Plenum, then the LIM and after the that its the block and heads, i mean wit the U and LIM removed i can see the pushrod and all of the jackets.
#23
Senior Member
Certified GM nut
![Default](https://www.gmforum.com/images/icons/icon1.gif)
ok so if i dont have to remove the heads, do i do the cranking after i reinstall everything to remove the fluids? because my setup has the Upper Plenum, then the LIM and after the that its the block and heads, i mean wit the U and LIM removed i can see the pushrod and all of the jackets.
Once the repair is complete and the new UIM is installed, then you can crank it without the spark plugs and that will all but drain the cylinders. That should fix almost every hydro-locked engine.
Reinstall the plugs, and as soon as it fires up, burns off any remaining coolant, and starts running smoothly, shut it down and change the oil. You can't change the oil enough during something like this.
#25
Retired Senior Admin
![](/images/badges/Gearhead.png)
Expert Gearhead
Join Date: May 2006
Location: Sheboygan Wisconsin
Posts: 29,661
Likes: 0
Received 29 Likes
on
25 Posts
![Danthurs is a name known to all](https://www.gmforum.com/images/reputation/reputation_pos.gif)
![Danthurs is a name known to all](https://www.gmforum.com/images/reputation/reputation_pos.gif)
![Danthurs is a name known to all](https://www.gmforum.com/images/reputation/reputation_pos.gif)
![Danthurs is a name known to all](https://www.gmforum.com/images/reputation/reputation_pos.gif)
![Danthurs is a name known to all](https://www.gmforum.com/images/reputation/reputation_pos.gif)
![Danthurs is a name known to all](https://www.gmforum.com/images/reputation/reputation_highpos.gif)
![Default](https://www.gmforum.com/images/icons/icon1.gif)
Chances are, the engine is fine. It filled when not running. But each time you try to crank it you jam a dry bearing and risk damage, so no cranking it until the plugs are out. Replace the plugs with new after you fix the leak. It'* going to run real bad for a little bit, but will smooth out. Replace LIM and UIM gaskets along with the UIM.
#26
DINOSAURUS BOOSTUS
![](/images/badges/Gearhead.png)
Expert Gearhead
![Default](https://www.gmforum.com/images/icons/icon1.gif)
OP... do not reuse that UIM w/o plugging the coolant holes or replacing it. Was the LIM full of coolant? The LIM gaskets should have a very tough time of filling the cylinders with coolant if they are bad. Becuase the chance of coolant running from one port on the head to three others w/o seeping into the valley or externally would be nearly impossible.
If you had coolant in the LIM, then look in the EGR hole of the UIM. You will find a crack or weakness that allowed coolant into the engine.
As for plugging those ports. It keeps this problem from ever being able to happen again. 95NASTA has done this many times, I've done this multiple times..it'* not a bad thing. You just want to do a good job and be neat about it.
If you had coolant in the LIM, then look in the EGR hole of the UIM. You will find a crack or weakness that allowed coolant into the engine.
As for plugging those ports. It keeps this problem from ever being able to happen again. 95NASTA has done this many times, I've done this multiple times..it'* not a bad thing. You just want to do a good job and be neat about it.
#27
Senior Member
Posts like a 4 Banger
Thread Starter
![Default](https://www.gmforum.com/images/icons/icon1.gif)
day 3, i just finished puttin everything back together. all bolts and nuts hoses elecetrical connectors. lettin it dry and will start the crankin test tomorrow afta i get off work.
i was jus thinkin, should i disable the fuel system and leave the thermostat out until im completely done after i change the oil about 3 or 4 times ?
my fingers are still crossed.
i was jus thinkin, should i disable the fuel system and leave the thermostat out until im completely done after i change the oil about 3 or 4 times ?
my fingers are still crossed.
Thread
Thread Starter
Forum
Replies
Last Post
Pepin
Everything Electrical & Electronic
4
07-25-2011 04:00 PM
Chiefjaybird
1992-1999
3
01-20-2008 09:05 AM
1995, 1999, 3800, antifreeze, bonneville, coolant, cylinders, grand prix, hydrolock, leak, lim, manifold, misfire, pontiac, repair, uim, upper intake manifold