98 4.0 lower radiator hose

Post here for all your technical questions or comments. - Jeep Only
Post Reply
EffiktivTJ
Posts: 10
Joined: Thu Oct 27, 2016 8:31 pm
MIJC Member: No
Full Name: Matt Morris
Location: East Peoria

98 4.0 lower radiator hose

Post by EffiktivTJ »

Hey all,

I changed my lower radiator hose on my 98 the because it was leaking, but the leak hasn't stopped. Can someone recommend somewhere I can take it that won't cost me a fortune. Or someone willing to give me a hand. It's driving me crazy and I need this thing back on the road. Thanks

Matt
LarryWilson
Posts: 163
Joined: Thu Jul 29, 2010 3:59 pm
MIJC Member: Yes
Full Name: Larry Wilson
Member page: http://mijc.org/members/u-z/wilson-larry-jennifer/
Location: East Peoria, IL

Re: 98 4.0 lower radiator hose

Post by LarryWilson »

Hi Matt,

Welcome to the forum! Most of us in the jeep club work on our own vehicles so recommending a repair facility might be a little difficult. But we do have a good knowledge base so hopefully that will help you. Coolant leaks can be annoying and frustrating to find. But I am confident that you can find the leak and repair the problem yourself.

The first thing I would do is to get a coolant pressure test kit. You can rent them from your favorite location auto parts store. Make sure that the engine is cold you don't want to burn yourself with hot coolant. Remove the radiator cap and attach the pressure tester. The radiator cap will have stamped on it the maximum psi for the cooling system. For that vehicle, I believe it is 16 psi. Then use the tester to build pressure in the system going no higher than what is stamped on the radiator cap. Then inspect the radiator and hoses for leaks. Pay close attention to where the tanks (the black plastic pieces that have the upper and lower hose fittings) connect to the cooling fins (the aluminum) on the radiator. I am willing to bet that you have a leak in the radiator above the lower hose and it is making it appear that the lower hose is leaking.

I hope that this gets you pointed in the right direction. Let us know what you find!

Larry
EffiktivTJ
Posts: 10
Joined: Thu Oct 27, 2016 8:31 pm
MIJC Member: No
Full Name: Matt Morris
Location: East Peoria

Re: 98 4.0 lower radiator hose

Post by EffiktivTJ »

Thanks for the reply Larry. It's definitely coming from the lower hose where it connects to the block. I changed out the radiator originally because I thought just that but it was still leaking. Realized after that it was from the lower hose but after changing that and now examining the old hose it looks fine, and I still have a leak. It's hard to see where it connects but it feels like it's on the all way. But I still have a leak. I'm assuming something could be cracked but I have no way to really see that.

I've always worked on my own vehicles and hate paying someone to do anything for me but I'm to the point of frustration with this one.
LarryWilson
Posts: 163
Joined: Thu Jul 29, 2010 3:59 pm
MIJC Member: Yes
Full Name: Larry Wilson
Member page: http://mijc.org/members/u-z/wilson-larry-jennifer/
Location: East Peoria, IL

Re: 98 4.0 lower radiator hose

Post by LarryWilson »

Ok, now that you have told us everything you have done, it will be a little easier to give you direction. The lower radiator hose connects the radiator to the water pump. Before you dive in and replace that, rent the pressure tester from the auto parts store. There are several places in the small area around the water pump could it could be leaking from and putting pressure on the system will help you identify where the leak is. Below are a list of possibilities:

1. There is a metal heater hose elbow at the top front (passenger side) of the engine. Those elbows do rust out.
2. The thermostat housing and or gasket could be leaking.
3. The water pump gasket or the water pump itself. There should be a weep hole on the bottom side of the water pump in line with the shaft. If it is leaking from there,
LarryWilson
Posts: 163
Joined: Thu Jul 29, 2010 3:59 pm
MIJC Member: Yes
Full Name: Larry Wilson
Member page: http://mijc.org/members/u-z/wilson-larry-jennifer/
Location: East Peoria, IL

Re: 98 4.0 lower radiator hose

Post by LarryWilson »

Ok, now that we have a little more information, we can get you headed in the right direction. The lower radiator hose connects the radiator to the water pump. Before you dive in and replace that, rent the pressure tester from the auto parts store. There are several places in the small area around the water pump that it could be leaking from and putting pressure on the system will help you identify where the leak is. Below are a list of possibilities:

1. There is a metal heater hose elbow at the top front (passenger side) of the engine. Those elbows do rust out and just screw in place. Pretty easy fix.
2. The thermostat housing and or gasket could be leaking. Pretty easy fix.
3. The water pump gasket or the water pump itself. There should be a weep hole on the water pump in line with the shaft. It could be leaking from there. OR you could see a leak around the shaft where the fan is attached. If it is leaking from there, the water pump is bad and needs replaced. To see this better you might need to take off the serpentine belt, fan and pulley. Doing this will give you more visibility overall.
4. It is possible that the head gasket could be leaking or worse case it could be cracked. (Did the engine over heat? Did you have the correct mixture of coolant? We did have a couple of nights of below freezing temps. Did this start after that?)

Below is a link for a video on replacing a water pump.


Keep me posted,

Larry
EffiktivTJ
Posts: 10
Joined: Thu Oct 27, 2016 8:31 pm
MIJC Member: No
Full Name: Matt Morris
Location: East Peoria

Re: 98 4.0 lower radiator hose

Post by EffiktivTJ »

Its leaking right around where the hose attaches to the water pump. It seemed to be leaking worse after I changed out the hose yesterday. It's been going on for a while but I have just been putting it off and mainly driving my second vehicle. After your post I drained the coolant again and pulled the hose to make sure it was actually on (it was). It's definitely leaking from around there and not the front where the fan is. The engine only over heated when the coolant got too low, when coolant was full or even half full it was normal temps. It only actually over heated once when I was on the highway and luckily I had water with me. And it was fine the rest of the way back to East Peoria from Bloomington. So doesn't sound like the head gasket (fingers crossed) seems to me like the issue is the water pump.
LarryWilson
Posts: 163
Joined: Thu Jul 29, 2010 3:59 pm
MIJC Member: Yes
Full Name: Larry Wilson
Member page: http://mijc.org/members/u-z/wilson-larry-jennifer/
Location: East Peoria, IL

Re: 98 4.0 lower radiator hose

Post by LarryWilson »

From what your describing, it does sound like a water pump. It is not too bad of a job to do. That video should help a little. Just take your time and you will be fine. (I know it is easier said than done.)
User avatar
wdln
Web Admin
Posts: 1577
Joined: Wed Jan 26, 2005 10:23 am
MIJC Member: Yes
Full Name: Dave Lennie
Member page: http://mijc.org/members/k-o/lennie-dave-carrie/
Location: Bartonville, IL
Contact:

Re: 98 4.0 lower radiator hose

Post by wdln »

It sounds like you've got it figured out, but the other thing I was going to suggest is to use a quality american-made hose clamp so you can tighten it down without stripping it, and make sure it's positioned optimally on the hose and pipe. If you get it on there crooked or too shallow, part of it could be on the outer retaining ridge of the pipe, which might cause a leak. Or not on the hose enough.

I spent the summer chasing a bad leak on my wife's '99 Cherokee. Tried new hose clamps first (P.O. had already replaced the hoses and radiator), that didn't do it. Replaced the water pump, but it kept leaking. Finally Frank and I tackled the head gasket, which was definitely leaking oil (so it wasn't a bad idea to do it), but it was inconclusive on leaking coolant. Got done, had a coolant spot on the driveway the next day, but then no more the rest of the week. I replaced one more hose clamp that looked suspect and it's been good ever since. So it could have been one of those things, or all of them, or just the stupid hose clamp. I'll never know.
Image___Image___Image___Image
. . . . . . '83 CJ-7 . . . . . . . . . . . . '89 Grand Wagoneer . . . . . . . . '78 Postal DJ-5 . . . . . . . . '99 Grand Cherokee ZJ . .
EffiktivTJ
Posts: 10
Joined: Thu Oct 27, 2016 8:31 pm
MIJC Member: No
Full Name: Matt Morris
Location: East Peoria

Re: 98 4.0 lower radiator hose

Post by EffiktivTJ »

This seems to be where I am at. I will look more after work today but I changed the waterpump this weekend ( Put a new thermostat and belt because why not.) Waterpump and thermostat look to be original which is crazy to me. But after I got everything back together it was still leaking yesterday then I had to work. Threw the catch pan underneath it and left. Started it up this morning and moved it back into the garage and checked for leaking, and nothing. And the pan didn't have as much coolant in it as I expected.

I will say this is definitely one of the most frustrating things I have had to deal with.

wdln wrote: Tue Nov 12, 2019 1:54 pm It sounds like you've got it figured out, but the other thing I was going to suggest is to use a quality american-made hose clamp so you can tighten it down without stripping it, and make sure it's positioned optimally on the hose and pipe. If you get it on there crooked or too shallow, part of it could be on the outer retaining ridge of the pipe, which might cause a leak. Or not on the hose enough.

I spent the summer chasing a bad leak on my wife's '99 Cherokee. Tried new hose clamps first (P.O. had already replaced the hoses and radiator), that didn't do it. Replaced the water pump, but it kept leaking. Finally Frank and I tackled the head gasket, which was definitely leaking oil (so it wasn't a bad idea to do it), but it was inconclusive on leaking coolant. Got done, had a coolant spot on the driveway the next day, but then no more the rest of the week. I replaced one more hose clamp that looked suspect and it's been good ever since. So it could have been one of those things, or all of them, or just the stupid hose clamp. I'll never know.
EffiktivTJ
Posts: 10
Joined: Thu Oct 27, 2016 8:31 pm
MIJC Member: No
Full Name: Matt Morris
Location: East Peoria

Re: 98 4.0 lower radiator hose

Post by EffiktivTJ »

EffiktivTJ wrote: Mon Nov 25, 2019 7:46 am This seems to be where I am at. I will look more after work today but I changed the waterpump this weekend ( Put a new thermostat and belt because why not.) Waterpump and thermostat look to be original which is crazy to me. But after I got everything back together it was still leaking yesterday then I had to work. Threw the catch pan underneath it and left. Started it up this morning and moved it back into the garage and checked for leaking, and nothing. And the pan didn't have as much coolant in it as I expected.

I will say this is definitely one of the most frustrating things I have had to deal with.
I'm going to say the gasket didn't sit correctly on the water pump. Its leaking 10x worse than it was before.
TSEJEEPERS
Posts: 2609
Joined: Thu Jan 27, 2005 10:14 am
MIJC Member: Yes
Full Name: Tom and Sally Evans
Member page: http://mijc.org/members/e-j/tom-sally-evans/

Re: 98 4.0 lower radiator hose

Post by TSEJEEPERS »

Check your thermostat housing and gasket out. It is pretty easy to crack the housing if the thermostat does not stay in the right position.
I use a little RTV on the thermostat itself to keep it in place.
It's hip to be square!!! []lllll[] NVRDUN9 93 YJ SOA XJ spring stretch, High pinion 9" rear Detroit locker, Dana 44 front ARB locker, 4.56 gears, Sanden OBA, Warn M8274 winch, 36" Iroks, Turtle enterprises swing out tire carrier
TSEJEEPERS
Posts: 2609
Joined: Thu Jan 27, 2005 10:14 am
MIJC Member: Yes
Full Name: Tom and Sally Evans
Member page: http://mijc.org/members/e-j/tom-sally-evans/

Re: 98 4.0 lower radiator hose

Post by TSEJEEPERS »

EffiktivTJ wrote: Mon Nov 25, 2019 2:01 pm
EffiktivTJ wrote: Mon Nov 25, 2019 7:46 am This seems to be where I am at. I will look more after work today but I changed the waterpump this weekend ( Put a new thermostat and belt because why not.) Waterpump and thermostat look to be original which is crazy to me. But after I got everything back together it was still leaking yesterday then I had to work. Threw the catch pan underneath it and left. Started it up this morning and moved it back into the garage and checked for leaking, and nothing. And the pan didn't have as much coolant in it as I expected.

I will say this is definitely one of the most frustrating things I have had to deal with.
I'm going to say the gasket didn't sit correctly on the water pump. Its leaking 10x worse than it was before.
Torquing every thing to spec is the key here. If you do not have a manual get one.
It's hip to be square!!! []lllll[] NVRDUN9 93 YJ SOA XJ spring stretch, High pinion 9" rear Detroit locker, Dana 44 front ARB locker, 4.56 gears, Sanden OBA, Warn M8274 winch, 36" Iroks, Turtle enterprises swing out tire carrier
TSEJEEPERS
Posts: 2609
Joined: Thu Jan 27, 2005 10:14 am
MIJC Member: Yes
Full Name: Tom and Sally Evans
Member page: http://mijc.org/members/e-j/tom-sally-evans/

Re: 98 4.0 lower radiator hose

Post by TSEJEEPERS »

As Dave said if you are using the original spring clamps get rid of them and get some quality clamps.
It's hip to be square!!! []lllll[] NVRDUN9 93 YJ SOA XJ spring stretch, High pinion 9" rear Detroit locker, Dana 44 front ARB locker, 4.56 gears, Sanden OBA, Warn M8274 winch, 36" Iroks, Turtle enterprises swing out tire carrier
EffiktivTJ
Posts: 10
Joined: Thu Oct 27, 2016 8:31 pm
MIJC Member: No
Full Name: Matt Morris
Location: East Peoria

Re: 98 4.0 lower radiator hose

Post by EffiktivTJ »

I will do that. Do you recommend using RTV on the gasket itself, or ditching the gasket and using RTV?

I did change the clamps out. Mostly for ease of use haha.
TSEJEEPERS wrote: Mon Nov 25, 2019 3:19 pm Check your thermostat housing and gasket out. It is pretty easy to crack the housing if the thermostat does not stay in the right position.
I use a little RTV on the thermostat itself to keep it in place.
TSEJEEPERS
Posts: 2609
Joined: Thu Jan 27, 2005 10:14 am
MIJC Member: Yes
Full Name: Tom and Sally Evans
Member page: http://mijc.org/members/e-j/tom-sally-evans/

Re: 98 4.0 lower radiator hose

Post by TSEJEEPERS »

LarryWilson wrote: Sun Nov 10, 2019 7:02 am Hi Matt,

Welcome to the forum! Most of us in the jeep club work on our own vehicles so recommending a repair facility might be a little difficult. But we do have a good knowledge base so hopefully that will help you. Coolant leaks can be annoying and frustrating to find. But I am confident that you can find the leak and repair the problem yourself.

The first thing I would do is to get a coolant pressure test kit. You can rent them from your favorite location auto parts store. Make sure that the engine is cold you don't want to burn yourself with hot coolant. Remove the radiator cap and attach the pressure tester. The radiator cap will have stamped on it the maximum psi for the cooling system. For that vehicle, I believe it is 16 psi. Then use the tester to build pressure in the system going no higher than what is stamped on the radiator cap. Then inspect the radiator and hoses for leaks. Pay close attention to where the tanks (the black plastic pieces that have the upper and lower hose fittings) connect to the cooling fins (the aluminum) on the radiator. I am willing to bet that you have a leak in the radiator above the lower hose and it is making it appear that the lower hose is leaking.

I hope that this gets you pointed in the right direction. Let us know what you find!

Larry
This is the best advise that has been given to you. Yes I know it looks to be expensive. You will get your money back after you use it though. I am sure most parts stores will work with you on it.
It's hip to be square!!! []lllll[] NVRDUN9 93 YJ SOA XJ spring stretch, High pinion 9" rear Detroit locker, Dana 44 front ARB locker, 4.56 gears, Sanden OBA, Warn M8274 winch, 36" Iroks, Turtle enterprises swing out tire carrier
TSEJEEPERS
Posts: 2609
Joined: Thu Jan 27, 2005 10:14 am
MIJC Member: Yes
Full Name: Tom and Sally Evans
Member page: http://mijc.org/members/e-j/tom-sally-evans/

Re: 98 4.0 lower radiator hose

Post by TSEJEEPERS »

EffiktivTJ wrote: Mon Nov 25, 2019 3:47 pm I will do that. Do you recommend using RTV on the gasket itself, or ditching the gasket and using RTV?

I did change the clamps out. Mostly for ease of use haha.
TSEJEEPERS wrote: Mon Nov 25, 2019 3:19 pm Check your thermostat housing and gasket out. It is pretty easy to crack the housing if the thermostat does not stay in the right position.
I use a little RTV on the thermostat itself to keep it in place.
No keep the gasket. I put some RTV on the thermostat to keep it in place.
Sure use some RTV on the gasket it self.
It's hip to be square!!! []lllll[] NVRDUN9 93 YJ SOA XJ spring stretch, High pinion 9" rear Detroit locker, Dana 44 front ARB locker, 4.56 gears, Sanden OBA, Warn M8274 winch, 36" Iroks, Turtle enterprises swing out tire carrier
EffiktivTJ
Posts: 10
Joined: Thu Oct 27, 2016 8:31 pm
MIJC Member: No
Full Name: Matt Morris
Location: East Peoria

Re: 98 4.0 lower radiator hose

Post by EffiktivTJ »

Just an update, fixed everything, threw on the RTV and no more leaks....there. Apparently my heater core is out as well. and I just went out to the garage to quite a bit of oil under my rear axle...I'm having a hell of a time with this damn jeep
Fraser
MIJC Treasurer
MIJC Treasurer
Posts: 993
Joined: Wed Jan 26, 2005 12:14 pm
MIJC Member: Yes
Full Name: Fraser Yarker
Member page: http://mijc.org/members/u-z/yarker-fraser/
Location: Pekin, IL
Contact:

Re: 98 4.0 lower radiator hose

Post by Fraser »

It's a Jeep thing.
1998 TJ (Wrangler) - usually driveable
19xx J-truck
Parts
EffiktivTJ
Posts: 10
Joined: Thu Oct 27, 2016 8:31 pm
MIJC Member: No
Full Name: Matt Morris
Location: East Peoria

Re: 98 4.0 lower radiator hose

Post by EffiktivTJ »

Fraser wrote: Fri Jan 17, 2020 12:51 pmIt's a Jeep thing.
If that isn't the most accurate statement.
User avatar
wdln
Web Admin
Posts: 1577
Joined: Wed Jan 26, 2005 10:23 am
MIJC Member: Yes
Full Name: Dave Lennie
Member page: http://mijc.org/members/k-o/lennie-dave-carrie/
Location: Bartonville, IL
Contact:

Re: 98 4.0 lower radiator hose

Post by wdln »

Jeeps are surprisingly unskilled at keeping fluids where they are supposed to be. However, a rear diff cover gasket is a cheap and fairly easy repair, and it gives you an excuse to change out the gear oil. If the puddle is in the middle of the rear axle that's probably all it is. It could also be the pinion seal, which is also fairly easy. If the puddle is near one of the ends... that could be an inner or outer axle tube seal, which is a little more involved.
Image___Image___Image___Image
. . . . . . '83 CJ-7 . . . . . . . . . . . . '89 Grand Wagoneer . . . . . . . . '78 Postal DJ-5 . . . . . . . . '99 Grand Cherokee ZJ . .
EffiktivTJ
Posts: 10
Joined: Thu Oct 27, 2016 8:31 pm
MIJC Member: No
Full Name: Matt Morris
Location: East Peoria

Re: 98 4.0 lower radiator hose

Post by EffiktivTJ »

Unluckily enough my rear diff was gone. I ended up just towing it and paying to get it fixed because that's out of my wheelhouse. Got my Jeep back last Monday and surprisingly there's a lot of sounds that aren't there anymore haha. Driving great so far other than the little no heat situation 😂
wdln wrote: Sun Jan 19, 2020 9:21 am Jeeps are surprisingly unskilled at keeping fluids where they are supposed to be. However, a rear diff cover gasket is a cheap and fairly easy repair, and it gives you an excuse to change out the gear oil. If the puddle is in the middle of the rear axle that's probably all it is. It could also be the pinion seal, which is also fairly easy. If the puddle is near one of the ends... that could be an inner or outer axle tube seal, which is a little more involved.
TSEJEEPERS
Posts: 2609
Joined: Thu Jan 27, 2005 10:14 am
MIJC Member: Yes
Full Name: Tom and Sally Evans
Member page: http://mijc.org/members/e-j/tom-sally-evans/

Re: 98 4.0 lower radiator hose

Post by TSEJEEPERS »

What brand of thermostat did you install and did it have a bleed hole?
What temp?
It's hip to be square!!! []lllll[] NVRDUN9 93 YJ SOA XJ spring stretch, High pinion 9" rear Detroit locker, Dana 44 front ARB locker, 4.56 gears, Sanden OBA, Warn M8274 winch, 36" Iroks, Turtle enterprises swing out tire carrier
Post Reply