lt1 leaking radiator

[Oldskool153]

Ok so the past few times I had the vet out I've been smelling antifreeze but could not find a leak anywhere, than yesterday I comeout and there a small puddle under her. I hooked it up to a pressure test and found that the bottom of my radiator has a small drip, I bought Bars liquid copper and I'm hopping that will hold until spring when its warm, my question is how hard is it to swap the radiator? I changed one on my lt1 z28 is this gona b anything like that? Vet is a 92 with an auto

 

[gmjunkie]

Ok so the past few times I had the vet out I've been smelling antifreeze but could not find a leak anywhere, than yesterday I comeout and there a small puddle under her. I hooked it up to a pressure test and found that the bottom of my radiator has a small drip, I bought Bars liquid copper and I'm hopping that will hold until spring when its warm, my question is how hard is it to swap the radiator? I changed one on my lt1 z28 is this gona b anything like that? Vet is a 92 with an auto

No,It's easier than a 93 up Z28!!
Have the radiator repaired or replaced,It's probly got a cracked tank!!Don't dump that crap in your car,it will only stop it for a little while if at all and probly cause more problems down the road!

 

[Rex S]

I'm with Junk, don't use the stop leak. Changing the rad isn't a big job the worst part is burping the system when refilling it. I always use the GM pelletts too. Yea I know it's stop leak but the GM stuff never clogs anyting.

 

[vetteboy86]

It was fairly easy when we did my brothers 87 vert. Other than some annoying froze up fittings, things were a breeze. It is also a fantastic time to clean this area out!!

 

[KANE]

No,It's easier than a 93 up Z28!!

Having owned an equal number of Vettes and Fbodies- Agreed. And Jesse- he is speaking from experience too!

Don't dump that crap in your car,it will only stop it for a little while if at all and probly cause more problems down the road!

Amen Jesse!

I'll go further... you wouldn't drink glue to stop bleeding when you need stitches? Same concept!

Drain what is left, pull the radiator, and get it repaired. Piece of mind is PRICELESS!

 

[Oldskool153]

Lol well its alil late considering I already put it in, in know its only a tempoary fix and will prolly blow out the 1st time I take her on the highway an build up any kinda pressure but ita january in NJ an I'm hoping I can make it till spring without changing it considering I work on my cars outside. - drove my z for a few months with stopleak b4 the crack got too big. Now u guys say its easier than the z, but what exactly has to come out on the vet for me to pull the radiator out?

 

[John Robinson]

The Nuts, Screws, and anything that holds it in place.

 

[Oldskool153]

The Nuts, Screws, and anything that holds it in place.

Funny guy u are lol

 

[vetteboy86]

Don't dump that crap in your car,it will only stop it for a little while if at all and probly cause more problems down the road!

What is the preferred method to clean a system out that has had this crap or another product added to the cooling system?

 

[Hib Halverson]

Avoid using stop leak products.

Here's why...they work by coating the entire inside of the cooling system with a thin pliable coating that sometimes "plugs" leaks by flowing into the minute passage that makes the leak, then getting "stuck" there.

When you continualy add more stop leak, or in the case of the other member who posted, the GM "pellets," you are adding more and more coating to the inside of the system.

The problem is this coating also inhibits heat transfer from the metal parts of the cooling jackets to the coolant.

So, using stop leak is a "fool's errand". Yeah, it might temporarily fix a very small pinhole leak in your radiator, but once that leak is "plugged" the cooling system is slightly less efficient. Add successive coatings via either more "Bars Leak" or more GM pellets, and you slowly but surely reduce your cooling system's efficiency by a noticeable amount.

Of course, you eliminate some of this inefficiency when you change radiators, but the coating that's inside your engine block's and cylinder heads' cooling jackets is there at least until you overhaul the engine and may even be there permanently.

The moral of this story is, never use any "stop leak" product in a high-performance engine.

The GM pellets are a one-time treatment for engines fitted with aluminum cylinder heads which demonstrate a documented problem with porosity. The GM pellets were not intended for "stop leak" use in systems with leaking radiators. Typically the factory service manuals of mid/late-80s and early 90s L98s make reference to these pellets but also states they are a one-time use product intended for engines which have coolant leakge due to cylinder head porosity problems.

 

[vetteboy86]

So what is the best way to clean a cooling system out that has been exposed to these additives?

 

[John Robinson]

Hibs Answer

Hib is right about the coating effect and the loss of cooling efficiency. Your question is if you have already done the dirty deed just how much measurable efficiency is lost. The cooling system as in most everything else in the car has been engineered to have a safety factor well above the expected normal day to day use. With that in mind Hibs reply in a single application case would probably reduce the overall design safety factor and not the normal operating temperature needs. With that in mind if you change the radiator the process of dumping all the fluid and putting in new will probably be all you need to do. With that said be aware that if the system for whatever reason has displayed a leak in the radiator it is a sign that the whole system may be compromised. By that I mean if you fix the radiator and are able to build pressure again then the next weak spot in the system will show up. That may be a hose or the heater core etc. so be prepared to chase leaks until you get the whole system back to a stable condition