4.0 Death

bootlegger · 01-08-2014, 11:13 AM

Engine went to 260 and blew a hose in my xj.Now she won't stay runnin. I'm assuming head gasket went.203k on the clock.Do I fix, replace or repower? Tight budget. I like little 4 cyl. diesels though......?

monkeystrong · 01-08-2014, 12:11 PM

Depends.. if its the gasket, then replace and keep on truck'n. if its the head itself, then I would start looking for options.

WrenchMonkey · 01-08-2014, 12:36 PM

Tight budgets and diesel conversions do not go together...

Fixing what you have is almost always cheaper. Even if you have to replace the whole engine, a bolt-in replacement is going to be faster, easier and cheaper.

bootlegger · 01-08-2014, 12:59 PM

I guess I'll get the head off and go from there.I'm just thinking it's probably cracked.
BTW i was just reading that there's a 4.0 poweresd vehicle in the current Dakar rally.

humpy · 01-08-2014, 02:54 PM

Put a tstat and new hose on and try it first... It's likely not runnin because of lack of coolant I noticed both if our 4.0 engines don't run right without coolant system sealed up and coolant in them ..., or u may have frozen it and junked it ... Is that possible?

bootlegger · 01-08-2014, 03:15 PM

Something is freezing up.The crank pulley is smoking the belt.Accys are barely turning. I'm thinking water pump or power steering.

WrenchMonkey · 01-08-2014, 04:12 PM

Quote:

Originally Posted by bootlegger

Something is freezing up.The crank pulley is smoking the belt.Accys are barely turning. I'm thinking water pump or power steering.

Oh, well if it's just an accessory, you're definitely better off fixing. Pull the serp belt, and see what won't turn by hand. Easy.

Unless you were looking for an excuse to bump up to a V8. I don't mean to discourage that!

GPER · 01-08-2014, 05:10 PM

Quote:

Originally Posted by bootlegger

I guess I'll get the head off and go from there.I'm just thinking it's probably cracked.
BTW i was just reading that there's a 4.0 poweresd vehicle in the current Dakar rally.

There are two Jeeps in the Dakar and the top one was in 94th spot as of yesterday.

bootlegger · 01-10-2014, 05:32 PM

After removing the belt , everything turns freely!!??
Good news is the oil looks fine and it drove back to the barn ok.I think i will change t stat, put a new hose and belt on ,fill up on critter killer and hope for the best.

tjrider · 01-10-2014, 07:27 PM

My tj over heated at big rock last summer cause my electric fan motor gave up. It ran like **** for a while after I cooled it down, then was fine. They have to relearn after over heating

WrenchMonkey · 01-10-2014, 09:49 PM

Quote:

Originally Posted by tjrider

They have to relearn after over heating

Depends on the year. Pre-91 was Renix, and stone simple.

Overheated mine at DTOR after filling the radiator with mud. Cleaned it out and went on my merry way. No learning required...

bootlegger · 01-18-2014, 05:49 PM

Update: Today I put a new t-stat, water pump, upper hose and distilled water/ prestone mix and she seems fine.What a relief!!! And right before the snow started to fly.
It ran for way too long with the gauge pegged at 260 before I could get it off the road.So I was sure that it was going to be damaging.
BTW I'm a huge believer in Motorkote and I run it in all my vehicles.

WrenchMonkey · 01-18-2014, 06:10 PM

Good deal!

For what it's worth, I'm a huge believer in the 4-0. Awful hard to kill the bastards!

underpowered · 01-18-2014, 09:36 PM

Quote:

Originally Posted by WrenchMonkey

Good deal!

For what it's worth, I'm a huge believer in the 4-0. Awful hard to kill the bastards!

x2.

the 4.0 in my old 95 ZJ has had the temp gauge buried multiple times, ran at the rev limiter for extended periods of time, been on Fire, and just generally beat on and still fires up and runs like a champ through all the abuse.

01-08-2014, 11:13 AM	#1
bootlegger Join Date: Nov 2012 Posts: 59	4.0 Death Engine went to 260 and blew a hose in my xj.Now she won't stay runnin. I'm assuming head gasket went.203k on the clock.Do I fix, replace or repower? Tight budget. I like little 4 cyl. diesels though......?

01-08-2014, 12:36 PM	#3
WrenchMonkey Mechanical Animal - CORE Member - - Moderator - Join Date: Feb 2008 Location: Beechmont Posts: 1,883	Tight budgets and diesel conversions do not go together... Fixing what you have is almost always cheaper. Even if you have to replace the whole engine, a bolt-in replacement is going to be faster, easier and cheaper. __________________ DIRTY DEEDS, DONE DIRT CHEAP Whatever doesn't kill you makes you stranger

01-08-2014, 02:54 PM	#5
humpy Join Date: Sep 2008 Posts: 573	Put a tstat and new hose on and try it first... It's likely not runnin because of lack of coolant I noticed both if our 4.0 engines don't run right without coolant system sealed up and coolant in them ..., or u may have frozen it and junked it ... Is that possible? __________________ S10 with a few air shocks..

01-10-2014, 07:27 PM	#10
tjrider Join Date: May 2009 Location: fairfield Posts: 320	My tj over heated at big rock last summer cause my electric fan motor gave up. It ran like **** for a while after I cooled it down, then was fine. They have to relearn after over heating __________________ If you don't want it broke, don't let me drive it....

01-18-2014, 06:10 PM	#13
WrenchMonkey Mechanical Animal - CORE Member - - Moderator - Join Date: Feb 2008 Location: Beechmont Posts: 1,883	Good deal! For what it's worth, I'm a huge believer in the 4-0. Awful hard to kill the bastards! __________________ DIRTY DEEDS, DONE DIRT CHEAP Whatever doesn't kill you makes you stranger

01-08-2014, 12:11 PM	#2
monkeystrong Señor Monkey Join Date: May 2012 Location: Georgetown, Ohio Posts: 185	Depends.. if its the gasket, then replace and keep on truck'n. if its the head itself, then I would start looking for options.

01-08-2014, 12:59 PM	#4
bootlegger Join Date: Nov 2012 Posts: 59	I guess I'll get the head off and go from there.I'm just thinking it's probably cracked. BTW i was just reading that there's a 4.0 poweresd vehicle in the current Dakar rally.

01-08-2014, 03:15 PM	#6
bootlegger Join Date: Nov 2012 Posts: 59	Something is freezing up.The crank pulley is smoking the belt.Accys are barely turning. I'm thinking water pump or power steering.

01-10-2014, 05:32 PM	#9
bootlegger Join Date: Nov 2012 Posts: 59	After removing the belt , everything turns freely!!?? Good news is the oil looks fine and it drove back to the barn ok.I think i will change t stat, put a new hose and belt on ,fill up on critter killer and hope for the best.

01-18-2014, 05:49 PM	#12
bootlegger Join Date: Nov 2012 Posts: 59	Update: Today I put a new t-stat, water pump, upper hose and distilled water/ prestone mix and she seems fine.What a relief!!! And right before the snow started to fly. It ran for way too long with the gauge pegged at 260 before I could get it off the road.So I was sure that it was going to be damaging. BTW I'm a huge believer in Motorkote and I run it in all my vehicles.