1991 Pontiac Trans AM 305 TPI, my baby has overheated today and when I arrived at work it was at 260 or almost to it. I noticed it from the shuddering the car was doing, I opened my door and heard a grinding sound. IMMEDIATLY turned the car off, my coolant was boiling, no smoke though and everything else seems fine. Fans still running ect. ect.
Now my question is, was that the water pump or did I spin a bearing loose? I need to know pretty soon, and if or not it would be adviced to drive it home (20 minute drive, if traffic is merciful) or should I get it towed home?
Also could I have warped anything in this process.

More info: I did not notice anything leaking from the weep hole on the pump.
It has overheated once before (low coolant).
Everything on block is iron heads, pistons, ect. ect.
I am unaware of how long it was heated this time.
I was parked and at idle when I noticed it overheat.

 

If it's boiling over, then it's definitely overheating. If the fans were running, then you have a deeper problem. If it's grinding, that's something metal rubbing on something else metal.

Check your oil, is it "milky" or have bubbles in it?

 

Sorry should have added, my fans are on a toggle switch. But one of the fans just went out... lovely.
But just checked the oil, It is still at level, and color was good and there was no grit in there as well, I didn't notice anything milky and no bubbles.

I just turned it over and no grinding happened at start. So, does that leave the bearings out of this and could be solemnly water pump?

Edit:Car was still over 100 degrees after an hour but not to running temp.

 

One fan should be enough to keep the car cool. Is your AIRDAM intact?

I would fill the radiator with water for now. Run the car at idle with the one fan on, it shouldn't overheat. Listen for the grinding you heard.

If you hear the grinding constant, and it's "loud", then you may have internal damage. IF you have a broom handle or a long screw driver, put that on the water pump and put your ear up to it...see if you can hear the grinding you heard earlier. Move the handle/screw driver around the motor at various places....use it like a stethescope.

 

Our 84 sounded like a piece of junk (gravel, grinding sound) when idling which I thought was due to exhaust. After replacing it, engine still did not sound right, quieter but sound was still there. Short time later, antifreeze leak from water pump. Replaced pump and grinding sound went away and car sounds good.

Can you take a long screwdriver, put end on water pump and handle to your ear and the hear the grinding sound through it?

 

Sorry Ozz, posting at same time, I just took too long!

 

My radiator is full, the overflow is over half full and the coolant is clear as day clean. I sadly don't have a long enough screw driver to do that while the car is running.. Think a long stick would work?

 

A good solid stick may work also, just be very careful of moving parts.

 

Just to add, When mine went out on my 88 5.7, Overheated, grinding noise like you mentioned. Scared the heck out of me. I replace the pump after I took tension off belt and tried to turn the WP.......not good. crunch crunch crunch.
After replacement, all was well. Hope you are as lucky as I was.
Good Luck!

 

I'll give it a try on my lunch break in an hour.

 

Any long stick/broom handle. needs to be solid though. If you have a jack-handle that would be about the perfect length (1-2ft long).

 

Alright, so I took it for a drive and today is about 90 degrees. So, it ran fine, but at idle it hesitated a bit. I did NOT hear any grinding while driving and my temp stayed current at 195 how it usually does.
But I put a stick up to it (probably 1/2 inch diameter solid chunk of wood, I have no good resources because my lunch is only 30 mins and job is far from reach of anything useful). I heard slight grinding, but nothing severe, nothing like how it did sound.

Should I just go ahead and replace it and call it a day or should I wait for further signs? Pump is only 30 dollars new, I'm just deciding how long it will take because I have work again tomorrow and need to get there.

 

If you can swing it, get a NEW GM pump, not a rebuilt piece of crap or you'll be doing it again a short time down the road. Spend the money now and be done with it. My GM pump is going on 10 years vrs. 18 month Auto Zone. Remove and replace is a bout 2 hours for me, it's not bad.

 

Oh it'll be new no worries there. I would get a GM pump but the PDC in my area is only open when I am working :P. I never go to Autozone, they always screw up even on a simply sensor they screwed up. I go to Advance Auto Parts, but that must be a preference thing.
and 2 hours, did you have to move anything, alternator, powersteering ect.ect?

 

Mostly the upper Radiator shroud, Bypass hose to Throttle Body, belts or belt, pulley off the pump, Water pump hose's, then unbolt.
But if you are THAT far, replacement hoses and T-Stat wouldn't hurt. Especially in Oklahoma City....I been there in the summer!
I know you need the car for work tomorrow, but just wanted to throw that out there...

 

1RAMAIRWS6 Might as well, the thermostat is only a year old, but who knows if it just got damaged. And as long as I can get to sleep at midnight, I can survive at work with a NOS or Redbull.

I want to thank everyone for the advice and help! I love this community, I just locked up my other account and was in a state of distress and couldn't remember my password! :P So I made this account!!

Thank you again everyone. In a few hours I'll be super greasy but the car will be happy!

 

We're all here to help where we can!!!!!!
Good Luck and keep us posted.

 

Might i add...get a bottle of hyper lube-super coolant...coolant additive..Keeps your temp Low...20· difference...in a 16oz bottle...find at walmart or any auto part retailer....im just using water and this additive...my temp stays below 185· at cruising speeds and idle...(dual fans connected to toggle switch)

 

To all who it may concern! Water pump was not the problem, I am going to change it with a heavy duty one though come the weekend. The real problem was with the alternator.. No ****, let me explain. The grinding noise was something internally wrong with the alternator, it locked up thus making my belt stop moving (gets better) it got so hot sp quick on my belt tension pulley that it warped it... So, replaced everything, pulley, alternator, belt, fuse for fans, relay for fans and cleaned out my air filter(it was due) runs like a champ again.
so learned today, bad sounds can always be a crappy reman alternator you bought at AutoZone. Hahah.

I hope this information helps. Any questions?

 

U can use a piece of rubber hose also .. That's what I've always used as my engine stethoscope lol ... Bout a 3 ft piece of 3/8 rubber fuel line or vacuum hose etc.

91' bird 305 TBI T-5, trick flow 175 cc heads, 4.10 gears, lots of suspension upgrades. 24mpg @ 2500rpm hwy. 8.80@ 84mph 1/8th on street tires... 8.000's soon

 

Well glad you found the problem and it wasn't too painful. Lol