re the oil change.


I would also do a compression check on the engine. If you hydrolocked while the engine was running, even just idling, there is a chance that you bent a connecting rod. The fact that the engine runs at all implies that if a rod is bent, it is not too badly bent. But the compression check should reveal a bent rod as a cylinder with significantly lower pressure. Because lots of other things can cause low compression, I would not attribute a low reading to a bent rod unless the difference was pretty large, maybe 40-50 pounds lower than the rest. If you find a low cylinder, you could then do a cylinder leakdown test to determine if the leakage past the valves or rings was greater in that cylinder than the others. If the leakdown in the low cylinder is comparable to the other cylinders, a bent rod would be indicated. I would be concerned that a bent rod would pretty quickly spin its rod bearing, and damage the crankshaft journal.

I was planning on running the fresh cheapie oil I just put in for maybe 50 miles and then replace with the good stuff. Understood on the compression check. I've not done a compression check before ever, on any motor, and I know I must do one to get an accurate idea of whats happening in there. But is there a quick means or a gut feel for any of the issues noted? Motor starts right up, seems to have healthy idle w/ no suspicious noises. I've not done other than just idle and move from garage to driveway at this point. The hydrolock occured a week ago as I started engine, it idled rough for about 15 secs. then sputtered and stalled - after this misadventure, I drained coolant from #1, R&R all other plugs, pulled LIM - R&R gaskets and seals, R&R funky cracked plastic bypass fitting, new thermostat and gasket/seal (which leaks...dagnabit!).
Thanks for your continuing help! It is appreciated.

From your description, it is possible that there was no rod damage done. The coolant entering the cylinder would first foul the plug causing the rough running, then as the piston tried to pump out the coolant through the valves, that would slow the engine, and maybe stop it before any serious damage occurred. I would suppose that the more suddenly the engine stopped, the more likely you would find a bent rod. Still, the forces here are really gigantic in terms of one connecting rod stopping a running engine, even at idle.

It is all a matter of degrees. If you have a bent rod, the worse it is, the more quickly it will damage the crank. If you did not bend a rod at all, you will have no problems. The compression check is just a means to discover a problem before it becomes a bigger and more expensive problem. It would be possible to change one connecting rod with the engine in the car for the cost of a cylinder head gasket, oil pan gasket, one rod bearing and one connecting rod. (I'll bet you could find a serviceable rod here on BC cheap.) The gaskets you just installed could most likely be re-used with no problems. That could maybe be done for $100-$150. If the crank is damaged, the engine will have to come out, and you will be looking at $400 -$500 to put it right.

I don't know of a cheaper or easier way to check this out than a compression test. You can buy a tester for about $20.

Thanks Bill. I'll check that compression today and post my findings.
A million thanks.

Well, here'* the latest. I've not yet done a compression check yet BUT, After replacing the LIM gasket and seals, the cracked plastic bypass fitting and replacing the thermostat and fixing a weeping leak around the thermo housing (I'd missed scraping old gasket crust from the housing, once done and resealed, leak was no more) and also throwing in some new spark plugs. I can now say that I cant see any coolant leaking anywhere. I filled the coolant resevoir to the correct level and I'll keep a close eye on it. I drove about 6 miles, varied the speed quite a bit and let her sit and idle for about 10 mins. No leaks, no overheating. It runs and sounds great. Exhaust appears normal, not whitish and sweet smelling as it had been. I'm gonna drop the cheapo oil and replace with Mobil 1 tommorow.
The only negative is that the check engine light came on and the idle became a bit rough momentarily a couple of times. Any idea why that might be occuring? I feel like I'm over the hump here thanks to the great advice. I can't thank you all enough.

Try this:

http://www.bonnevilleclub.com/forum/...e=article&k=57

And report the codes back here.

What about your O2 sensor? Fastest way to smoke one is to burn coolant.

Another point of coolant leakage (external) centers around the o-rings going into the water pump/coolant pipe fitting and the smaller coolant pipe o-ring that goes into the intake manifold. I had slight leakage for a while and those o-rings were the culprits. (And no, for some strange reason they did not get replaced during the rebuild). Though external leakage may not be your problem now, it may be in the near future since you tore into the top end.

Hey Sand,
I was just checking out the possibilty of a wasted O2 sensor. I'll bet you're right. I'll have the counterjockeys at Advance Auto throw a code reader on it and see if it is indeed the O2 sensor. I would be thrilled to spend another $35.00 to get a new one and be done with my coolant burning days!

Do NOT buy a Bosch or low-grade sensor. You'll be replacing it very soon.

Spend the money for a Denso or AC Delco only. Our experience on this has been proven time and time again.

Let'* have the codes. Check the link I posted above. You can pull your own codes. You don't need a store to do it, and bias you with what they want to sell you.

Well, I threw a new O2 sensor in, tried to get Delco or Denso, Advance had neither in stock. BUT they sure did have the Bosch in stock ! I groaned and bought it. Wasn't cheap though, 54.00. I saved receipt to go back on 'em if it fails within a year.
The car ran great all weekend, no leaks, no heat buildup...all was good. Went out this morning to start her and noticed a puddle of coolant on driveway and a pretty good drip feeding it after it ran for a minute. I don't know where the external leak could be! Very frustrating. I'm gonna go try to locate it now. I'll post my findings. If anybody k nows a suspect place to check please advise.
Thanks.