Need some help! Replaced head gasket, now motor is stuck!!
 

Hey everyone,


Bought a '97 XJ that was pouring out white smoke. I braced myself for the worst, but when I pulled the head the block and the head looked perfect, no cracks, so I replaced the head gasket. Got it all back together this morning, went to start her up and the motor locks up. I can turn it by hand to a certain point, then it's just stuck. What the heck could it be?


Just to let you know, I've been wrenching on my own stuff for quite a few years, have been inside a lot of cars and bikes, so I've been around the block a time or two with stuff like this. What stupid thing could I have done to cause this? Desperately need to get this going, winter is coming and a VW
Beetle is no fun driving 100 miles a day to/from work!! :oops:

The head was the only thing removed? Did u remove the pushrods/lifters? Positive nothing dropped onto the top of a piston?

There has to be something in a cylinder not allowing one of the pistons to come all the way up. Did you make sure wasn't any coolant in one of the cylinders hydro locking the motor?

I would think when turning by hand, rotation is so slow that any water in a cylinder would pass by the ring gaps, not be compressed, not cause a hydrolock.

Unfortunately cliffpenick hit the nail on the head. Pulled the plugs and rotated by hand again, when I hit the #1 cylinder (same cylinder that originally had the problem) coolant shot out the plug hole. Now I'm right back where I started. Just pulled the head again, nothing jumping out to indicate anything is wrong. Head gasket looks perfect, and still cannot for the life of me see any cracks in the head of block. I will have the head checked for cracks or warping, but I really would have thought that if it was warped it would be toward the middle of the head, not on the very end. Oh well, some days it just sucks to be me!! :mad:

That sucks buddy. There has to be a pretty major problem if the cylinder is filling with coolant without being pressurized. Crack in the cylinder wall will do that or warped head. Need to resurface head and get it checked for a crack.

Yeah, I'm pretty shocked it could fill up with enough coolant to lock it up that fast! I literally put oil & coolant in it this morning after buttoning everything up and bam! What really bothers me is that it was able to run before that, it smoked after it got hot, which it did pretty quickly, but it still ran. Not sure what the heck is going on, I'll have the head checked and go from there.

At least one head bolt that needs sealant is near #1. (might be front right, and the one behind it). They go into the coolant, (water jacket, my dad called it). How long was it? Over night, those two might have done that. :confused1:

I'll take a look.....

OK, it's "#11". That's the FRONT LEFT. The front left head bolt needs sealant to prevent coolant from leaking. (If I have this right).

^^ Spot on.

Yeah, I put sealant on that bolt, when I pulled the head last night it still had sealant on it and was pretty obvious that none had leaked past. I have the head in the back of my car, I'll see if I can find a machine shop to check it out.

OK, I'm taking the head to a machine shop tomorrow. 50 bucks to pressure test it, another 50 to machine it if it's warped. So the way I look at it I have 3 scenarios here. The best scenario is it fails the pressure test and turns out to be warped. The second "best" would be it fails the pressure test and is cracked. That means I have to find another head, and I could be right back where I started unless I have THAT head checked too. The WORST scenario is that is passes the pressure test. That more than likely means I have a cracked block.
I have an idea I'm going to try tonight, before I drop the head off. Whatever is wrong, it has to be pretty significant to fill the #1 with coolant in about an hour or so, under no pressure whatsoever. What if I put the drain plug back in the block, drop my #1 piston to the bottom of the cylinder, and fill the block with water through the water jackets? If there was a cracked wall or whatever, I would think the water would leach out into the cylinder overnight. Any thoughts? Am I looking at this right? In my defense I've got a nasty cold and I'm taking a lot of Nyquil, so my brain might not be working as well as it should be right now... :w00t:

Without the head and head bolts torqued down to spec, water testing the block for a cold water leak is not duplicating the conditions well enough for a definitive answer.

You would have to use a torque plate. That way you are isolating the block.

But you still have the problem that the test is not accurate, because the head would have coolant in it above the block. That would allow for gravity flow during a cold water leak.

In the final analysis, you may have to use the head for a door stop and buy a brand new one. I don't trust a used replacement head any more.

I agree, it won't be entirely accurate. But the way I look at it, if I come out in the morning and there is coolant in my #1 cylinder, I really don't need to get the head checked, do I? :mad:

Sounds like a fine plan. No cost, nothing to loose, and may turn something up. It's that kind of thinking that makes this country great! You may well learn something none of us expect. (actually you might expect that!)

Cold...1/2 inch Honey in cup, fill with hot water. Add apple cyder vinegar to taste. (I like allot, some..couple tablespoons). The vinigar changes the PH so the "invaders" are not happy, the honey is an antibiotic. The hot with steam and the "edge" of the vinegar is nice when you are all plugged up. This will do no harm, as oppose to industrial chemicals, which I myself avoid.

Agreed,> " if I come out in the morning and there is coolant in my #1 cylinder, I really don't need to get the head checked, do I? "