JackCooper

I saw it for sale at a small dealership and just had to buy it. A 1979 Corvette. It has a great body, no rust in the frame (pretty good for a beach car), matching numbers, a nice leather interior, power everything, t-tops, ect. I got it for 5500 bucks. It runs strong too. Has a 400turbo tranny in it. Ran great for about 3 days, then I started having some probs.

I just put a new fanclutch and water pump on it (The fan clutch was worn out, and I decided to replace the waterpump too because the car had been sitting up for a few years before the old man decided to get rid of it (he'd had back surgery and hadn't been able to drive it for a long time because it hurt his back, so he traded it even for a 97 minivan, go figure)), and now it overheats when I drive more than a mile.

I just got it, so I'm scared that there may be something bad wrong with the motor. It runs great and has good oil pressure though so that probably isn't the case.

After I let the car cool off for a while, I heard a hissing from under the hood. I looked and the top radiator hose was collapsed where no water could pass through it!

So, why would it collapse and could that be why it overheated. I'm somewhat beffuddled because the day I bought the car, it ran fine (although the fan clutch needed replacing) and I drove it home through heavy traffic with it running cool!
And it continued to run cool up until I replaced the water pump and fan clutch. I did a compression check on the motor before I bought it, and it has good compression, nothing seems mechanically wrong.

So I'm a bit confused.

Yall think that replacing the t-stat and the water hose should fix it?

Oh, and about retaining origionality, I bought the vette to drive and enjoy (I'd like it to be my daily driver if possible), but I don't want to kill the value. Replacing the waterpump and stuff like that won't hurt the value will it?
How about using base-clear paint instead of the type origionally used?

daily_driver

okay 1st off i wouldnt worry about a 79's "value".....

remember you dont buy a corvette to get any value back!!!

cuase you wont!!!

modify it and make it a great daily driver!!


id swap out the thermostat if i were you..... check the condition of the coolant... is it orange?? if its orange or dirty backflush the syste,///....

look through the radiator cap at the core and see if the core is rusted or what??...

is the system leaking?? high pressure leak?? brown spots through fins??

start with the thermostat though...

if your gonna make it a daily driver then swap out that @#$@!!@@ fan+clutch for electric fans and toss that shroud also.

welcome to the world of vettes!

:)

daily_driver

u can buy dual electric fans at summit racing pretty cheaply...

people think the flex o lites suck but they are great for stock engines.....

JackCooper

Thanks.

What about the hose, why is it collapsing?

The coolant is new (I just drained and replaced it
with antifreeze mixture when I replaced the waterpump).

The radiator appears to be in good condition.
The system is not leaking.

Is there something wrong with the '79 vette?
I thought I was getting a good deal.

Allow me to tell you a little about myself.

I'm a 17 year old high school senior. I rank top of
my class, and I had always wanted a corvette, so
my parents gave me $6000 to buy an old vette for
my graduation. My Mom told me that I can work on it, ect,
but not to do anything that will diminish its value to less
than I have in it (IE, don't mod it unless the mod increases
value).

The car only has 97,000 origional miles on it, and all the numbers
match (block, tranny, rear end, body, ect).

Could I modify it for performance without diminishing the value if
I only do mods that I can 'undo' later (such as electric cooling fan)
without hurting the resale value (I don't plan on ever selling it, but
that was the stipulation my parents made).


[Modified by JackCooper, 12:54 AM 11/8/2001]

Flareside

I'm not entirely sure about '79s, but most large radiator hoses have a wire spring inside them specifically to prevent collapse. Some aftermarket hoses omit the spring. I would order the OEM rad hose.

How about a picture of the new car?

-Joe


[Modified by Flareside, 7:59 PM 11/7/2001]

79MakoL82

Hose collapsing makes me suspicious. First, replace the hose that collapsed. If it's that soft it needs replacing. If it is too soft, the collapse could cause an obstruction that would overheat the car. The other thing is that I have to believe that it is collapsing for a reason, like trying to suck a McDonalds shake through a straw. If your sucking on one end, and it's obstructed on the other, the straw will collapse. I would definately replace the thermostat. It's a $3-$8 part (depending on the quality of the replacement part). I recommend the 180 degree variety. If this is not opening, it will cause your engine to run hot. Also, have the radiator checked. Just good policy. Obviously, your water pump is working because you have the suction to collapse the hose. I would try the T-stat and hose first though because they're cheap, easy and likely culprits. I would still have the radiator checked though.


[Modified by 79MakoL82, 7:18 PM 11/7/2001]

daily_driver

what i mean is that u dont buy a vette to make money on it... thats for sure..

and dont think youll ever get all the money you put into it back!!!!

a 79 is a great year vette if your into that turtle back style!! :)

what im saying is dont worry about originality with a 79!!

modify it anyway you like it!!

it sounds to me for 5500 u got a good deal....

the reason you buy a vette anyways is to enjoy it.


what u want to check is take that old themostat out and boil it... if it dont open then that was the problem.... but boil the new one at the same time just to verify it works... believe it or not ...but ive gotten new thermostats that dont work!!! its amazing how a 3 dollar part can blow your engine up...
btw: go with a 180 thermostats... u dont need a 195 !!

my top hose doesnt have a spring in it... although the bottom hose definatly should have one!! (usually you xfer the old spring to the new one....)

checkout the t-state and get back to us...

make sure u dont go crazy torquing down the t-stat housing bolts as many people have broken em off that way (use a torque wrench... they are only 25 bux!!)

Shutdown1

Hey Jack,

You might just want to take the old thermostat out for a while and see if it still overheats. While it's out take off the radiator cap (engine not hot!) and look to see if the new water pump is pumping water or not. You should be able to see water movement inside the radiator if it is. At this time why don't you check to see if there's any water on your oil dipstick which might mean you have a gasket or leaking problem somewhere in the engine. - Little changes like electric fans, etc. aren't going to hurt the value of your car. Keep us posted on what you find. Regards, PM '74 Turbocharged 350, "Molested to Perfection" class of '71

Green76

Jack, I would first replace the radiator cap and also check out the hose for kinks/obstruction to the overflow tank. It sounds like you have a vacuum in the radiator when it starts to cool down and it probaby isn't able to pull antifreeze from the overflw tank back in to the radiator.

BSeery

I would go with thermostat -- replace it with a nice 180 degree unit and see how that does.

Good luck with it, you will love it when you can enjoy driving on nice day with the tops off and the sun in your face .......

79MakoL82

and the hose. Any basic automotive manual will tell you that if you can pinch the hose together, it needs replacing. If yours collapsed, it needs replacing.

shoptek

Jack,

Congrats on the new purchase!!!!! Any Vette is better than no Vette at all. :cheers:

Agree with the past posts. Try the thermostat and hose. I'll bet that is all it is.

Good Luck!!!!!

CharlieS

The 79 L-48 upper radiator hose does not have an internal wire; never did. The lower one, however, does.

Something simple; make sure the radiator cap is fully closed, or it can do exactly as yours is doing. "Been there; done that!" :smash:

ddecart

I'll concur with that. There's something in the system that isn't working properly. Personally I'd give it the once over and replace the thermostat & cap, both hoses, flush the radiator, make sure the lines to the expansion tank are clean & clear.

Dave

JackCooper

Well, I replaced the t-stat with a 180 degree unit.
I discovered that there was no t-stat in it to begin
with!!
I also replaced the hoses.

It is still overheating. :mad

Also, there is some black gunk in both the radiator
and the overflow tank.

I'm beginning to think that I may have bought a lemon, hehe.
Well, it can't be too bad.

Maybe I should take the radiator out and have it boiled and
rodded... is there anything else I should do you think?





[Modified by JackCooper, 1:18 AM 11/9/2001]

Shutdown1

Jack,


Tough luck on your first attempt. Hang in there though, you can fix it. I would suggest at this point (if you can determine that oil and water are not mixing together, and that your new water pump is functional) that you take the car to a radiator shop and let them pressure check your cooling system. They have probably seen this scenario before, and maybe can help you on a first-hand basis. With the new results you have given us, it is really hard to throw a lasso around this one. Maybe some of the other members can come up with something better. I'll do some head scratching for you. Please keep us posted. Your learnin' ! Regards, PM '74 Turbocharged 350, "Molested to Perfection" class of '71

79MakoL82

Absolutely, have the radiator worked and replace the radiator cap. This could cause the overheating and the hose collapse (even though I believe you needed a new one anyway). Also, check your fan clutch and your radiator seals. With the engine running and warmed up, turn the car off and watch the fan blades. They should only spin 4-5 times before stopping. If they spin more, you need a new fan clutch. Second, check your radiator seals. These are frequently deteriorated or missing and they work to force the fan to suck the air THROUGH the radiator instead of around it. If these are missing, they need to be replaced.

Even with the expense of these things, you've spent a lot less on your Vette than a new car, and you look a hell of a lot better.

Good luck. :cool:

GaryS

I guess I will play the idiot here, but you say the upper hose collapsed. :confused: The reason the lower hose has a spring in it is that the water pump sucks the water out of the lower portion of the radiator into the engine. This can sometimes collapse the hose. So why is your upper hose collapsing? I know that some of the later model GM cars had reverse cooling whereby the water enters at the BOTTOM of the radiator (I think). Is there any way that a reversed water pump was installed that flowed water the wrong way? Try disconnecting the upper hose and then running your engine with a water hose stuck into the top of the radiator. Is water coming out of the hose or out of the radiaotor? Obviously you must wait for the thermostat to open. If water is flowing properly, try replacing the upper hose. They are fairly cheap.
Gary

daily_driver

okay man holdup!!!

you gonna have the radiator cleaned out??? NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO!!!

i have pulled my radiator enough times to learn a valuable lesson!!

get it done up right the 1st time!!

get it recored!!

it only cost me $130 for my 4 core radiator to get it recored....

thats chump change compared to some of the corvette repairs heheheh....

i had my supposedly recored twice.... i pulled that stupid radiator so many times grrrrrrrrrrrrrrrrrrrrrrrr :cry :cry :cuss :cuss :cuss

daily_driver

btw: what kinda black gunk?? hope thats nots oil!!!

:eek: :eek: