Solving an Overheating Problem - Caused Hose to Burst

licenseTOill · Tue Nov 15, 2016 4:33 pm

My 2012 overheated today. I lost my heat and the temp gauge was hot. Under the hood I found a lot of coolant sprayed out in the left rear of the bay and I found a coolant line that had a hole.

My question is: Where does the coolant hose in the photo connect to or is it just a cap? The line in question is in the left rear corner on the head, next to the intake manifold.

LPSISRL · Tue Nov 15, 2016 5:12 pm

Just checked my 2011 SLS. It's a cap.

licenseTOill · Tue Nov 15, 2016 5:47 pm

Thanks! Maybe everyone needs to keep an eye on that cap. Aparantly mine blew apart.

Tue Nov 15, 2016 7:03 pm

So it has a solid end to the tube to serve as a cap?

licenseTOill · Tue Nov 15, 2016 7:28 pm

Yes, it appears that way. Maybe for use of this engine in a different vehicle.

licenseTOill · Tue Nov 15, 2016 7:30 pm

Fixed

licenseTOill · Fri Nov 18, 2016 3:06 am

Update on this overheating journey/struggle.

The cap I replaced failed again as I was driving to work the next morning. I now think the cap blowing out is the effect of a different problem. Pressure and temperatur build up in the engine just blew out the weakest point, which was that cap.

What I know: coolant in the engine gets hot. Really hot and into the red on the temp gauge and will boil eventually. (I think this is what caused the cap to blow out). The upper radiator hose is hot while the radiator cap, lower radiator hose, and air being pulled through the radiator remains cold.

I thought "ok, easy enough. The thermostat at the end of the lower radiator hose is stuck shut and not allowing the coolant to circulate. I'll replace it". Replaced it ($13 at autozone) and I am having the same issue.
Ok, next is the radiator cap. Took the cap to autozone to use their radiator pressure tester with the cap adapter. The original cap would not hold 16 psi. It bled down to 9psi before I cut the test short. Got a new cap ($6.99 at federated auto parts), pressure tested, held pressure to 16 psi, installed, and a very hopeful me was disappointed when the car overheated again with the same issue.

Next is the water pump, I may take the upper radiator hose off tonight and turn the car on to see if it is pumping water out of the hose or not. Water pump is around $230 at autozone.

That is where I stand so far

I may do a compression test and leak down next, after I rule out the water pump, to investigate the head gasket.

Any input?

LPSISRL · Fri Nov 18, 2016 5:43 pm

I think you're correct in looking at the water pump next. Hot engine, cold hose means no circulation. Since you ruled out thermostat, which typically fail open anyway, the pump would be the next logical step. The radiator could be plugged, but your coolant should be pretty gunked up if it was.

licenseTOill · Fri Nov 18, 2016 6:14 pm

Good point. I can't imagine the radiator is plugged. The car has 98k miles on it and had the original coolant. I had 2 bottles on hand because I was meaning to replace the coolant since the 90k mile service interval. I'll check the pump out tonight.

licenseTOill · Sat Nov 19, 2016 6:01 am

I tried testing the water pump today by pulling off a heater core hose and also the upper radiator hose. I got no flow out of them after starting the car. So unless I'm missing something, I thought that pointed to a water pump problem.

I removed the water pump, which was a pain in the *ss, and inspected. Well, it looked brand new inside and actually really well made. I cleaned everything up nice and put it back in. I also pressure tested my system to 16 psi with perfect results.

I'm going to finish putting the car back together tomorrow and then bleed the system really well before taking it for another test drive. No real rusts yet.