A couple weeks ago, temps got below 0 and on the way to work my jeep overheated and sprayed antifreeze all over the place. I had no choice but to take it to a shop that I had had bad experience with in the past. They said that all that was wrong was someone had put a hose clamp on too loose, and that the seal in my radiator cap was shot. I was happy with the cheap repair cost, and went on with life.
Late last night, it again blew and sprayed antifreeze all over everything, but the temp gauge did not read hot, I just felt a gradual loss of power and eventually noticed smoke/steam trailing me and pulled over. Had it towed to a different shop and they looked at it this morning, they said it had popped a rubber freeze plug out, but the mechanic is convinced there is something wrong deeper than that, and keeps saying he thinks it's a head gasket.
The plug that popped was the one under the intake and exhaust, so that's more than they can do at that shop (Big O tires).
My question: should I replace with another rubber plug temporarily so they can run some tests and see if there's another problem, or should I just take it to an engine shop and have them replace with a brass plug, possibly replacing the other plugs/head gasket/etc while they have it all apart?
edit: the tow truck guy looked at it, and said it looked like there may be something wrong with the water pump, but I replaced that about a year ago. He also said my coolant looked like it may have a little oil, but he couldnt really tell. When he dropped the jeep off, he said that all things considered, it looked like a thermostat problem to him. So there's that as well.
Also, I had noticed it had dropped a decent amount of fluid on the driveway yesterday morning towards the back of the engine. I normally park on gravel or rocks so I dont know how long it's been leaking, or what it was
I just called the shop, saying I had found a rubber plug (they had said they couldn't find any in town) and asking if they wanted me to bring it in so they could do what they had wanted to do, and I guess the guy thought I was a local parts store calling back, cause he said "nah don't worry about it, he's got deeper problems, we think his head gasket is blown." So apparently they're done with it.
My manager's brother in law runs the shop program at a local high school and he only charges parts, so I'm seeing if he is willing to work on it.
You've got a bunch of conflicting "casual" off the cuff diagnoses without anything definitive.
You need a shop and technician that can do the proper TESTING to determine true root cause here. I'm not confident that the shop you have your XJ at has that expertise.
Cooling systems are not rocket science; pressure tests and other testing can be done. For a suspected blown head gasket, I'd start with a compression test and also a block test where you sniff the coolant for presence of hydrocarbons.
I suspect you are in for another bad result with this shop. Get your XJ to another shop. Quickly.
99 Cherokee, 4.0 AW4, NP242
Past Jeeps: 49 Willys, 81 Scrambler, 88 Comanche Without "data", all you have is an opinion!
What year is your jeep? If you had smoke and loss if power it may be a head gasket. If its got the 0331 head it may be the head. Definitely sounds like the temp sending unit is bad.
It's a 98.
Originally Posted by tjwalker
You've got a bunch of conflicting "casual" off the cuff diagnoses without anything definitive. You need a shop and technician that can do the proper TESTING to determine true root cause here. I'm not confident that the shop you have your XJ at has that expertise. Cooling systems are not rocket science; pressure tests and other testing can be done. For a suspected blown head gasket, I'd start with a compression test and also a block test where you sniff the coolant for presence of hydrocarbons. I suspect you are in for another bad result with this shop. Get your XJ to another shop. Quickly.
This shop was going to do the compression testing, but couldn't because the plug was blown out and they said they weren't going to get into taking everything apart to replace the plug just to test it. The guy was nice enough not to charge me anything, and they don't mind if I leave it there for a few days until I find another place to take it.
I don't really know anything about anything under the hood except for how to bolt on alternators/starters/PS pumps/etc, but would you have to take the head off to replace this plug, or just intake and exhaust manifold? I couldn't really tell by the info he was giving me
A compression test can be performed without a cooling system hooked up. Heck, I've performed compression tests on engines out of the vehicle.
A compression test will test to see if each cylinder is compressing at the same psi, or if one has a leak (head gasket leaking) it has nothing to do with the actual cooling system.
If the compression test is good then install the rubber freeze plug and begin testing the cooling system. Figure out the problems there and after everything is working good then you can take it to have a metal plug installed.
Just the way I would proceed.....its advice on the internet. But for the record, I would trust anyone here to diagnose your jeep more than the shop you've got it at now if they make wild assumptions without any data to back it up.
Sent from my phone where correct grammar is difficult.
No tests, as the shop said they couldnt with no plug in it. My girlfriend's cousin works on diesels and he is willing to do everything for 400 including parts (head gasket and the plug) so I'll ask him if he can do the compression test before tearing it apart. If the test shows everything is fine, should I just not worry about the head gasket, even though the manifolds and all will already be off to replace the plug?
Thanks for the advice Holder, that's the course of action I would take if circumstances were different. However, it's too cold outside for my florida blood and I dont have a garage available where I live to work on it. The shop it was parked at wasnt willing to install the rubber plug to test it, and I didnt want to pay another $50-60 to tow it to a shop that would do what I wanted.
I believe the compression testing the shop was talking about was for the coolant system to see if it was getting too much pressure, rather than testing to see if the gasket was blown. My buddy offered to do it, he has the garage, tools, and experience necessary and the price was right. Didn't have to pay for a tow truck, and I'll have the brass plugs in all the holes and a new set of gaskets whether I needed them or not as well as a new t-stat.
He was going to put a rubber plug in and run the tests before tearing it apart, but there were none available locally and the old one was too torn up to use so I told him to go ahead and do the brass plugs and gasket.
I've been a week without a jeep and the roads are nice and slick and I also put a new light bar on the night it blew up, so I just want to get it back as soon as i can so I can go out and play.