Riding home on free way, first I noticed oil temps getting high checked coolant it was 20' higher then usual...I pulled off freeway to a gas station, I opened the hood heard a bubbling sound in radiator followed by my overflow overflowing with coolant..bad thermostat, water pump or bad radiator?...

 

Possible blown head gasket.

 

Pulled dip stick and checked oil cap, no oil and water are mixing...oil was clean

Mind you this wasn't a problem that gradually got worse(like a head gasket normally would) until this incident all temps have always been good.

The car never over heated I pulled over once I saw temps out of range..when I pulled over I cut the engine off and radiator made that bubbling noise and overflow started backing up as if the fluid had nowhere else to go, that has me thinking thermostat..

 

If exhaust gases entered the cooling system, you would see rapid over-heating, expulsion of coolant into the over-flow bottle due to excessive pressure. Contaminated oil would not be evident.

A ruptured head gasket can happen immediately, not necessarily overtime.

If you suspect a faulty t-stat, replace the t-stat, and see if you have solved the problem.

 

Ok.....

 

I'll know tomorrow when I swap out that thermostat

 

If it blew like that at hwy speeds wouldn't that cause a mix of oil and water by the time I reached the gas station I drove to, wouldn't white smoke come from tailpipes.? I've had head gaskets blow while driving and it was very easy to tell that's what it was...

 

If the head gasket breach only allowed exhaust gases into the cooling system, the oil would not be involved, and coolant would not exit the exhaust system.

The symptoms you present indicate exhaust gases are entering the cooling system.

 

Thermostat housing bolts won't budge...I'm sure it's the original 30 year old thermostat in there...gotta give it a PB Blast blast in the am and hope that works..

 

I had a Pontiac Grand Prix do exactly that same thing. It turned out to be a clogged radiator. I replaced it with a new one and the problem was solved.

 

If you have access to an impact wrench, it should remove the bolts, although clearance
may be a problem even with a flex shaft.

 

Okay, what a morning, long story short, bolt on tstat broke...it's now it's on the way to the shop, leave it to the professionals, I'm blessed to have access to a great shop here in town, they build race cars and compete. Theses guys know performance cars...so they'll fix the tstat, and I'll do the radiator myself..after inspection of radiator this morning, I know it's the prob...I'll take a pic in a few when I meet the tow truck at the shop...for lack of a better word to describe it, it looks cooked,

It seems like this is common right around 100,000 miles.(replacing radiator that is).in the 84vette.I just flipped 113,000...

 

this isn't terribly comforting. I just bought one with 115k miles on it haha. good luck with the repairs.

edit: and it's white eek

 

If it does turn out to be the radiator, this is the perfect opportunity to do an upgrade. Turn lemons into lemonade. The radiator on my '95 failled at 104K...I ordered a really nice one from DeWitt and installed it myself. No complaints at all...wish I had done it sooner...great quality and the peace of mind alone would have been worth it.

 

I have the original brass radiator, the aluminum ones sold now are an upgrade in its self..I just learned when purchasing my new radiator..

 

NO BETTER TIME THEN THE PRESENT..!

Took this unfortunate opportunity to go ahead and just do what I wanted, since the radiator is being put on, and he's due for his tuneup anyway, I just dropped off a box of goodies...so in a week or so I'll be back on the road a bit stronger then before, can't wait to see what that chip really does at full throttle...I know what it says it does, I WANNA FEEL IT!

Parts list:

Corvette HEI Distributor HiPerformance 19811984

MSD 6AL Multiple Spark Discharge Ignition 19581996

Corvette Spark Plug Wires Red SpiroPro Taylor 1984

Corvette Spark Plugs Rapidfire 2 ACDelco 19761984

Corvette Air Filter Element KN 1984

Corvette Alternator 120 Amp 19841985

Corvette Engine Starter Gear Reduction 19841996

Corvette Door Panel Insulators Left RightWhisper Quiet19841996

Corvette MaxPerformance Mufflers Borla LT1 19841991

Corvette Hypertech Street Runner Power Chip For Cars With Automatic Transmission
© 2014 Eckler's Corvette.

 

Awesome!!!

 

BTW, since you are on a quest for power, how is the cat (catalytic convertor) on that car?

A new modern, high flow cat to replace the old design (and likely partially clogged) thirty year old cat can make a noticeable difference that you can feel in the seat of the pants.

Then again, I don't know where you are located so perhaps the cat disappeared or was gutted years ago. Here in CA, the bi-annual smog inspections are a real pain so I went with a Magnaflow replacement which still has the required numbers stamped into the side that they need to pass the visual portion of the test. It really woke the car up!

 

Hey, thanks for the input.. I'm in Cali also, East Bay Area. The exhaust is actually going to be done at a different shop in Hayward, so I'm sure kent(mechanic)will tell me to do them if needed. Or not even needed, if he says "hey, you might as well do the cat while I'm down here. Everything in the list except a couple items are basic tune up parts, just "high performance" tune up parts, I know that info, but exhaust, I have no idea. So now knowing what you just educated me on, I'm sure another $200 won't break the bank..lol..I bought those parts over a few months time and been stacking to a point to when I was done buying parts everything can go on new at the same time. And after this radiator incident, I just said Do it!

 

Hey...very cool! Hadn't realized you were local. One of these days, it would be great to organize a local C4 get-together. I used to do those for a different kind of car before and it was always fun to have a bunch together at the same time.

For decades, I was all about getting new speed parts and bolt on speed. The last few years, I haven't been that way, but have been amazed at the loss and degradation of performance over time as common components age. Oftentimes it is like shocks...the effect is so gradual over time that you don't notice how bad they have gotten until you replace them with new ones. Same goes for a lot of engine components. Now more than ever I understand why when I was younger, everyone was telling me to get a solid baseline first before adding speed, it makes a big difference, especially on a twenty or thirty year old car.

Naturally, as with anything, it gets healthier and faster if you throw money at it...LOL

If you are passing CA's sniffer test then your convertor is likely still functioning well enough to pass, but a newer high flow cat (make sure it is CA compliant with numbers on it and welded on in a way that the smog guy can read it...believe it or not, both have been a major issue) flows so much better and is more efficient at the same time.

On my '95 and also the '90 that I used to have, both were running so well on the original ones that I thought it couldn't possibly make much difference, but I did it anyway. I was amazed at how much it helped...it just woke both of them up. Even the exhaust note was louder and healthier with the engine more willing to rev. Driveability was improved in all ranges and the car was a lot more fun to drive all around.

As always, each car is different, but in my case, it was some of the best money I spent performance-wise in a long time...definitely worthwhile. Two Magnaflow cats for the '95 was only $250 installed and the single cat for the '90 was even less. When it comes to cats and exhaust, I prefer a muffler shop to a mechanic since that is their forte.

Happy Saturday, all!!!

Roy