Coolant Issues

[adsm08]

Where my radiator/s were crimped together, they only leaked when hot. So you may be on to something there.

Most radiator tank seal leaks are temp sensitive because the plastic and aluminum expand/contract at different rates.

 

[black_demon69]

Over the years I've had more than one coolant hose continue to leak after a clamp problem, etc. It seemed like once they leaked for so long, they'd never seal no matter what style of clamp I used. A new hose fixed the problem.

I have in a pinch used gasket shellac on inner side of the hose then reclamp but can be a PITA too get off later.....

 

[adsm08]

So I messed with it some more today. I think my ultimate problem is that the cap seal is leaking when it tries to pull coolant back into the system from the tank, and then runs down the hose and drips off the low point, which is just about right for where I see drips, when I see them. I'm going to swap from the Ranger that barely gets driven and doesn't have this problem before I go spending money on parts that won't fix it.

I also apparently had a huge bubble in the system because the radiator hoses were collapsing and the rad was going into vacuum after the thermostat started opening. Filled it up the whole way (I think) so I will see how that goes.

 

[Rimjam]

So I messed with it some more today. I think my ultimate problem is that the cap seal is leaking when it tries to pull coolant back into the system from the tank, and then runs down the hose and drips off the low point, which is just about right for where I see drips, when I see them. I'm going to swap from the Ranger that barely gets driven and doesn't have this problem before I go spending money on parts that won't fix it.

I also apparently had a huge bubble in the system because the radiator hoses were collapsing and the rad was going into vacuum after the thermostat started opening. Filled it up the whole way (I think) so I will see how that goes.

I had to replace my '88 2.9 radiator due to a pass side tank leak. The new O'Reilly's radiator leaked on the OTHER side at the cap. A second known good cap leaked also. I had O'Reilly's replace the radiator because I was sure there was a driver side tank crack just under the cap, they did so without complaint. To my surprise the SECOND radiator leaked in the same place! Letting the truck idle for several minutes revealed small bubbles underneath the cap at the overflow hose nipple. A simple fix I tell myself, a small hose clamp & all is good - NOT! Still had a small leak. Remove the radiator & discover the nipple was miscast; the mold was crooked & so the two halves of the nipple were offset. Careful use of a file & a daub of RTV silicone finally solved the problem.