Had coolant hose blow off, need advise

OK so on my way home my nearly new (replaced 2 months back) top Radiator hose blew off. Hopefully it was just the worm-clamp had either come a bit loose, or while messing w/it I forgot to snug it down. So I watched my temp gauge and drove it about 2 miles ~ 35mph and the gauge got ~ 215 but not much more. I did pull over once and let it cool down a bit and put the clamp/hose back on and snugged it up.

When I got home, I had to put ~ 2 gallons of coolant in. Got everything buttoned up, cap back on radiator, no noticeable leaks... started it up and added a bit more coolant. Heater blowing HOT air. Took it for a drive ~ 2 miles and temp gauge was around 200 +/-...

Now for my question. The top radiator hose and bottom radiator hose never really pressured up even after the engine getting hot and driving it around a bit. It was 'squishy' and never hardened up w/pressure. I couldn't see any holes or leaks but those hoses have always pressured up when the engine comes up to temp. It's cooling down now and I'm going to go back out and check the coolant level to see if it needs more, but do you think this is anything to be concerned about?

2-core aluminum radiator, fresh thermostat and water pump and all hoses and clamps tight.

Thanks for any suggestions or reassurance that I'm just being paranoid and it's going to be fine.

Did you bleed the air from the cooling system after the repair? If not, that is your next step. In the future please do not trust your temperature gauge when you are having an overheating event and have lost coolant. Do not keep driving your Jeep, unless you really hate it. As you were seeing 215 or more you were not getting an accurate indication of the actual cylinder head temp. Unless you can fix the hose on the side of the road can replace the coolant and bleed the system, pull over and get a tow. It is easier than having to replace a head gasket or worse. Just to be safe, I would get a test for carbon monoxide in the coolant and check for water in the crankcase. BTW, a failing head gasket can cause over-pressurization of the cooling system. My girlfriend's Civic just had that happen. Blew the cap off the coolant reservoir and spewed coolant all over the engine compartment.

After you fully bleed the cooling system, let it cool to a safe temperature, carefully take off the radiator cap (lots of towels over the cap and wear leather garden gloves when you remove it) and run the engine. Check for bubbles coming up. If you notice even a few, it may be an early warning of a head gasket issue.

Blown head gasket?, do a compression test of each cylinder.

Thanks for the info. Ill keep an eye on the coolant etal.

I had the 0331 Cylinder Head replaced ~ 1 yr back. Has been running good since but hopefully nothing wrong w the gasket or head now.

Should I be concerned if the cooling system doesn't pressure up after the engine warms? After going thru the head crack incident I hate to have to mess with that again.

May be a nothing more than a bad radiator cap?

But If it got hot enough, which it sounds like it did, it killed the T-stat, which is now stuck wide open, making it run a lot cooler, and keeping the PCM in open loop longer. Replace the cap and T-stat.

Also did any coolant get on the O2 sensors? If it did it can kill them, making the engine run rich and cooler.

No idea if any coolant got on the O2 sensors... but it's possible. Coolant kind of blew all over the engine bay. I also flushed water all over the engine bay (gently) to wash off the coolant once it was cooled down and I had refilled the radiator.

Update: This morning was going to drive it to work (since I test drove it last night for a couple hours) and then this weekend if I didn't experience any problems I was going to do a compression check. BTW, just changed the plugs this past weekend and the 'old' plugs were in really good shape. Cleanly burned with just a bit more gap. Anyway, she won't start now. Just turns over and over and over. Never even hickups like it wants to start. No fire at all. Any ideas what it could be now?

(Seems like all my problems act up in the most inopportune time!! ... like us all)

What year, 4.0, auto?????

Define won't start?

Cranks or not?

Fuel?

Spark?

Sorry guys... thought I put that...

This is an '01 XJ, 4.0, Auto, 4x4.

It will turn over and over but never fires up. I am in my office work clothes so hadn't tried much other than pop the hood to make sure nothings leaking. Not sure if I have fuel or spark. Since it has Coil Packs not sure how to check that? It's giving symptoms of a bad Crank Shaft Position Sensor. Looks like the plug-in for that is in a different location than on my '96 XJ was.

you can try swapping the asd relay with another and see if that works, that's the only work clothes friendly thing I can think of, and caused me headaches for two years on my old xj

H8PVMT said:

you can try swapping the asd relay with another and see if that works, that's the only work clothes friendly thing I can think of, and caused me headaches for two years on my old xj

Click to expand...

I'm not sure what the 'asd relay' is? I caught a ride from my wife to work so the XJ is still sitting in the driveway at home... getting my game plan in order for tonight or tomorrow for working on my rig.

Thanks for the replies...

Automatic shutdown relay, big fat relay passenger side under the hood with the rest I them, same as most others so you can swap them around quick to see if its bad or not

Update:

It appears that it was the Crankshaft Position Sensor that had quit working. I went by the Dealership and bought a new Mopar CPS for $81... figured I'd stick w/the Mopar part since these are not fun to change out. After swapping in the new CPS my rig fired right up. Took it for a drive and the temp gauge warmed up to ~ 212 and then you could see it drop back down to ~ 200 +/- as the thermostat opened back up. Drove it for ~ 3 miles, stop and go, and when getting home popped the hood and didn't see any leaks. Both Upper and Lower Radiator hose were now pressurized as they should be. I got my laser temp gauge out and the temps were ~ 180-185 degrees on the thermostat housing. I had no signs of a blown head gasket but plan to run a compression test in the next couple of days just to verify. It's a PAIN to pull the Coil Rail and all the plugs and get access to the plug holes to run the compression test on my '01, but I'll just have to do it to be sure what's going on inside the engine.

Thanks again for all the tips and things to check. Will follow up after I get the compression test ran.

Not to bead a dead horse, but did you use the dealer-supplied T-stat? There's a reason that it has the little check-ball in it. Both our XJs and our Subie Outback use the check-ball T-stats, and it's to help the trapped air to bleed out.

Thermostat is a Stant Superstant. I've always had great success with those. The CPS is from Mopar.

I've used the Stant T-stats, and my '92 didn't seem to care. But, my '96 would always spike high with a Stant, rather far up, until it hit the temp at which it would open, then the temp would settle down. I put the proper one in, with the check-ball, and then it has behaved properly. Same deal with my Subie...It just didn't like a 'normal' 'stat. To the point where it would start to over-heat, run the fans too long, and set a CEL code. I replaced it with a genuine T-stat, one with a check-ball, and it's behaved ever since.

Just my $0.02!