# She broke down



## Norms68 (Jul 17, 2013)

Ok just got done towing the 68 goat back to the house.

Normal cruise around the country side. We stopped at a gas station and was in light traffic. Temp started to go up but that's normal for stop and go. Drove out on highway and temp went down to normal. Stopped again to turn around and temp started to go up. Got back on the highway to cool it off again but this time it just kept on going up and up. I had no place to stop (highway with kids in backseat) so took a chance to make it to next turnoff. Engine started to run rough as I turned off and stalled with temp spiking to max. Rolled to a stop popped hood and let her blow her steam. 

I got a friend to help and after it cooled got antifreeze and water. The top hose had nothing in. Filled radiator to top and cranked it over. She ran but really rough. Didn't seem to be getting water to top hose. 

So I'm guessing either thermostat or water pump.

My question now is if it caused internal damaged what should I look for? 

I only cranked it up once to try getting water through it and it ran really rough. Any thoughts?

Thanks,
-Norm


----------



## Cory (Mar 2, 2014)

Doesn't sound good. If it runs rough after it 's completely cooled off, and your not leaking fluids on the ground, or she sprayed coolant all over the ignition wires, then i'd start by:

Check the oil, see if it's overfilled and signs of any water in it. Might look like a nasty milkshake. Or if it's overfilled, you could drain a little out of the oil pan, if there's water, it will come out first as it is heavier than oil. If you find water in oil, the heads will need to come off, and further inspection is needed.

If the oil is ok, next I'd track down why it runs poor, before I would spend money on the overheating problem.

Good luck,


----------



## BearGFR (Aug 25, 2008)

Your symptoms sound like a thermostat stuck closed to me. As for the rough running, once you get the overheating sorted out the first thing I'd do would be to change/inspect the oil ("milkshake" brown means it's coolant contaminated and that could have several causes, like head gasket leaks and/or cracked head(s)/block). That's going to mean it has to come apart and may be history. If you dodged that bullet, then the next thing I'd do would be to run a compression test. Extreme overheating can cause the rings to lose their tempering so that they no longer seal. It'll still need to come apart but won't be as likely to be a goner. You'll probably want to have the block/head mating surfaces checked for straightness/flatness as they may have warped. I hope not, but you're probably in for some bad (and expensive) news.

Bear


----------



## chuckha62 (Apr 5, 2010)

Everything Bear said, but you should also pull your spark plugs and look for moisture. If your head gasket let go into a combustion chamber(s), you _could_ see moisture on your plugs. You won't always see it, but you should be able to. That alone will cause a misfire, rough running condition.


----------



## Norms68 (Jul 17, 2013)

Right before I went to work this morning I checked the oil. Looked great and at the right level.

For the next step I was thinking replace thermostat, check plugs(moisture) and wires, and if that checks out fire it up to see if it pushes water.

This might just be the excuse I need to get approval from the wife to finish my 461 stroker!


----------



## 68GTO4004Spd (Jun 19, 2008)

As the internets leading expert on Pontiac motors exposed to too much heat. I say your ONLY option is the 461 stroker.


----------



## geeteeohguy (Feb 2, 2008)

Everything these gents said, and I'll add this: I can't _count _the number of customers I had back when I was in the mainstream auto industry that said they 'just had to make it home' or 'to the next town', etc. with the oil light on, or the temp gauge pegged, etc. Could _not_ stop. Stopping right away always= cheap repair. Pushing on at all costs usually=$$$$$$$$. With cell phones and AAA, etc. no good reason not to stop asap, JMHO.


----------



## Indecision (Oct 24, 2010)

geeteeohguy said:


> With cell phones and AAA, etc. no good reason not to stop asap, JMHO.



This... I have AAA Platinum, I get like 4 100mi tows a year and 1 200mi tow per person. I used 3 in the last billing cycle... usually stupid stuff, but it pays for itself every year. I've yet to not use a single tow.



68GTO4004Spd said:


> As the internets leading expert on Pontiac motors exposed to too much heat. I say your ONLY option is the 461 stroker.


Also... yes.


----------



## Jared (Apr 19, 2013)

One good reason not to stop on the interstate is you can get killed doing so. I have personally seen the results of stopping for a flat tire on a busy interstate result in death. Sometimes there is not enough room to pull all the way off and no repairs are worth your life! Having the kids in the backseat, you definitely made the right choice. The car can be repaired, your life and your kids lives are way more valuable.

That being said, I hope your engine ends up being OK.


----------



## PontiacJim (Dec 29, 2012)

geeteeohguy said:


> Everything these gents said, and I'll add this: I can't _count _the number of customers I had back when I was in the mainstream auto industry that said they 'just had to make it home' or 'to the next town', etc. with the oil light on, or the temp gauge pegged, etc. Could _not_ stop. Stopping right away always= cheap repair. Pushing on at all costs usually=$$$$$$$$. With cell phones and AAA, etc. no good reason not to stop asap, JMHO.



What? You must have never owned a slant 6 car. Had one I was going to junk and I wanted to blow it up. Oil light just a blaring, water temp pegged, knocking, and I just couldn't quite seem to kill it. Cooled off, it ran great again. Just watch the movie Duel with Dennis Weaver and see the punishment that slant 6 takes. Took pushing it over the cliff to end it! HaHaHa. Now Pontiacs, had one overheat on the ex-wife from a blown hose and it was driven a distance and the rod knock soon followed - and the end of an engine (because you could buy another cheaper than rebuilding).


----------



## Norms68 (Jul 17, 2013)

Got a new thermostat to put in, a 160 F one. I only drive in summer and never use heater so I think that should be good.

Passenger side plugs checked out good. Driver's side #3 had moisture. Looks like I'll be pulling that head inspecting it and at least replacing the head gasket.

-Norm


----------



## Cory (Mar 2, 2014)

It's worth doing a compression test first. If you get weird numbers, I'd squirt a little oil in those holes and see if the numbers come up. That'll tell you what kinda condition the rings are in.


Also don't have any regrets for trying to make it off the freeway. I ran out of gas once in rush hour with my daughter in the back seat.. One of the scarest times in my life.


----------



## ALKYGTO (Mar 29, 2010)

Another test you can do before tearing it down is a coolant pressure test. They rent them at most auto parts stores and it pressurizes the coolant system and if there is a leak (head gasket) you will lose pressure. I highly recommend it as it doesn't take much time and probably won't cost you anything.

And as a father I agree with Cory in that you made the right call priority wise, family first. The car can always be fixed. Good luck.


----------



## Norms68 (Jul 17, 2013)

Thanks for the help and kind words guys. I'll do those checks.

-Norm


----------



## Norms68 (Jul 17, 2013)

This is what I found so far.

#1 Piston, on the top you can see the ring where it blew apart.










-Norm


----------



## PontiacJim (Dec 29, 2012)

Wow. Never heard of that due to overheating. I have read that a ring land can break from severe detonation, but that may have indeed been taking place due to the extreme overheating situation. Just curious, what type pistons? Piston lands can be placed differently based on the maker.


----------



## 666bbl (Apr 13, 2014)

Looks like you pulled off on "Detonation Alley"...


----------



## geeteeohguy (Feb 2, 2008)

Looks like a TRW/Sealed power part number for a forged piston. Seeing that it's .060" over, it looks like it's time for a new engine block or some sleeve work. As hot as it got, I would not trust the rest of the engine. I would suspect bearing damage, etc., looking at that broken piston.


----------



## Norms68 (Jul 17, 2013)

Yeah, I'm probably 50% complete with my 461 build on another block. Just have a few more big ticket items to save for :/

Slow process but she'll be back.

-Norm


----------

