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Got home from fishing today and after cleaning the fish, noticed a small puddle under my 1995 C1500 W/T with a 4.3 motor.... Got down to look and sure enough, is was "green" fluid..... Opened the hood and the puddle was on the driver's side top of the radiator.... on what appears to be some sort of hook up for a garden hose perhaps to flush the radiator???? There is a kind of weird looking ring nut threaded on this garden hose pipe fitting and the leak is right there at the bottom of this weird looking ring... I know the ring probably just unscrews, but what am I going to find under it????? a gasket that needs to be replaced that is perhaps shot? I looked on Rock Auto at the new radiators for this truck and see that this is a stock fitting on this radiator.... Anybody care to tell me if this is an easy gasket fix or what I should do? Unscrew the ring and see what is under it? Please advise.... and thanks.... PS... I will try to attach a picture of the Rock Auto radiator with a red circle around this weird pipe fitting on the radiator.......
better picture close up of leaking garden hose connection ring
I did some computer magic to get a better close up look at the garden hose connection ring on the radiator that is leaking... the leak is definitely coming out of the bottom of this connection...... Do I just unscrew the ring and look for a gasket? Cheap fix? DIY???? Thanks
I assume no hoses hooked to driver's side?
+1 for fittings for oil cooler - fittings on that side for my 93 Suburban are for oil, and passenger side for transmission cooler lines.
If it's leaking antifreeze I agree time for new radiator; nothing to tighten as the fittings would be carrying engine oil through radiator for cooling. Or find a radiator shop that could repair it - used to be lots around; no so much anymore in our disposable society.
My son happened to stop over this afternoon and he has a 1994 W/T so I took a look.... The lines running to these two connections were for his oil cooling lines..... Chevy made a lot of changes between 1994 and 1995..... and apparently there is some other oil cooler on my 1995 engine..... I cleaned up the area... filled up the radiator and let the truck run for 20 minutes.... no leak.... go figure... I suspect it only happens under higher speed pressure... time will tell.... Even though the truck is a 1995 it only has 75,000 miles on it.... and the water pump, hoses, etc. are all OEM.... so maybe it is time to just spend some money.... Thanks for the advice....
Oil cooler was an option, typically for tow packages so it wouldn't be unusual if your truck doesn't have it. If everything is OEM you re doing good and being lucky! I would for sure think about new hoses before one of them leaves you stranded.
Engine speed has no effect on cooling system pressure - it’s all about temperature. Pressure in the cooling system builds as the temp of the coolant increases - the water pump only circulates the coolant.
If you don’t have an engine oil cooler but the radiator has the fittings for it, it could’ve been deleted by a PO. If you saw coolant dripping from around the fitting then the radiator is leaking and will need replacement - there’s no gasket or o-ring that can be replaced as they are sealed during manufacturing from the inside. Whether or not it leaks at a given time is dependent on the overall temperature of the the radiator (not the coolant). The engine can be at operating temp and the thermostat open but the radiator still cool (relative to engine temp) and so it won’t leak. But after significant work and running time (long drive, for example) the radiator expands enough to start leaking.
Get the engine nice and hot - a controlled brake stand around 1500 RPM for 2-3 minutes (once it’s up to operating temp) will usually create enough heat to cause the leak to come back. Once you’ve gotten everything hot, shut off the engine - this allows the pressure to build even more as air is no longer being drawn over the radiator and dissipating heat.
Oil cooler was an option, typically for tow packages so it wouldn't be unusual if your truck doesn't have it. If everything is OEM you re doing good and being lucky! I would for sure think about new hoses before one of them leaves you stranded.
This is a work truck so we assumed a few things when we found it for sale..... I had restored my son's 1994 after buying that with an engine problem that was an easy fix.... and learned a lot about work trucks.... I assumed that all of them had posi..... like the 1994..... and after researching a bit, found out that mine does not have this and his does.... His has an oil cooler as the option and mine does not..... I am going to use this truck to go the five miles to the lake where I fish on Monday and then take a look once again... but in the meantime, I will be looking for a new radiator, and yes, my only "fear" in changing the radiator myself are getting the transmission coolant line removed.... and put back, without a leak.... Anybody got any advice about that? Heat from a small butane torch first? I have found that "penetrating oil" is way over rated..... but will listen to other suggestions.... a mechanic I learned from way back in the 60's used a vice grip instead of the proper wrench, and distorted the nut on the end of the line..... nothing but grief after that.... so I need to listen and learn.... Advice, suggestions welcome..... PS.... I also got the OEM numbers off the upper and lower hoses to replace them at the same time.... This is not a daily driver, especially in the winter, so I can afford to wait for a leak in the water pump... and yes, I have changed one on a 1998 Blazer with a 4.3 because all the shops were two weeks out at the time.... and a mechanic friend who owns one of these shops said to "go for it" and take your time.... He would help if something went wrong but it did not.... Time to listen.... thanks!!!
Penetrating oil is like any other tool - it has its limits. You can increase your chances of success with it by cleaning the line fittings with a wire brush and compressed air - soak them for a day, then repeat until you’re ready to remove them.
A line wrench or a closed crows foot type socket is the best tool for taking the lines off, but what usually happens is the fittings are so corroded that they round off no matter what. However if you’re gonna be replacing the cooler lines, I’d suggest just cutting them off at the transmission and using a socket.
By 95 I'm pretty sure the transmission lines were held in by a metal clip. You remove the clip and simply pull the line out of the radiator. The new radiator will probably come with the clips installed, if not install the clips you removed from the old radiator and the simply push in the transmission lines until they are captured by the clips, be sure they are fully seated and can't be easily pulled back out and you are good to go. Radiator changes in this series of trucks are easy, drain, remove hoses and transmission. oil cooling lines that are easy to reach, remove screws holding the shroud and remove the upper shroud, this should make access to the other lines easy, lift out radiator, reverse to install.
May 21st, 2020, 2:16 PM
radiator leak help
