Georgia Trail Riders Forum

MEMBERS DISCUSSION AREA => General Discussion => Topic started by: Nick_Knipp on January 24, 2011, 08:03:06 PM

Title: MJ loss of power
Post by: Nick_Knipp on January 24, 2011, 08:03:06 PM
sup yall, just drove to Atlanta and back today, it was scary as hell. ever since i started it this morning it doesnt seem to get going when i push the gas pedal hard(accelerating) but it does catch up real slow, takes about 2 mins to get up to 60 lol. i pulled over, pressed on the clutch and reved up the engine to its max and doesnt seem to have problems getting the high idle. however when I'm on I75 going up very slight hills (I HATE hills!) it bogs down alot and speed drops to like 45-50. the gas pedals floored in and I'm in 4th and 5th, and it still aint going. once i get over the hill i can speed up again to like 60-65. but it still bogs when i floor the gas.

when i just entered atlanta it was getting worse and i started to smell something burning.. i pulled over for gas as well, popped the hood and saw oil all over the head. the 2 lines going into the top of the head were loose. oil was leaking all over the concrete, but my oil dipstick doesnt show serious loss of oil. and i knew that wasnt good. so i got the tape and held them down real good. arrived at my friends and helped her out. when we were done my jeep had been sitting for a good hour. i started back up and it seems to be fine til i got back on the interstate heading out of atlanta, then it started doing the bogging thing all over again. when i pulled over for gas i tapped the gas tank real good and filled her up. got back on the highway and seems to get some improvement, going 55-60 up small hills.

I'm at loss, tomorrow I'm taking out the tank and cleaning it first thing. then put the gas in my other jeep for daily driving. what does it sound like to you? lines are okay and in right places. filter, fuel pump, fuel pump filter, all are brand new and I had a friend from the jeep club help me install them.
Title: Re: MJ loss of power
Post by: ranger11 on January 24, 2011, 09:39:39 PM
I would start with the dented fuel tank. I dont know how your gonna do it but  I think you need to undent it as its dented right where the pick up sits in the tank.
Title: Re: MJ loss of power
Post by: rabunjeeper on January 24, 2011, 09:50:31 PM
It could have low compression. Being that your hoses were blown off your engine, that tells me maybe you have excessive blow by and it can build up enough crankcase pressure to blow the hoses off. You can tell by starting the engine, then removeing either the oil cap or pcv valve and see if its blowing steam up out of the valve cover.
Title: Re: MJ loss of power
Post by: Nick_Knipp on January 24, 2011, 09:50:48 PM
idk if it is dented, doesnt seem like it is. is it really?
Title: Re: MJ loss of power
Post by: ranger11 on January 24, 2011, 09:53:05 PM
Andy I said the same thing about the blow by.  My old 4.0 use to do it.


Nick look on the bottom of the tank or better yet post a pic I will circle the dented area.
Title: Re: MJ loss of power
Post by: S14unimog on January 26, 2011, 03:46:36 PM
I agree about the blow by scenario.  Might as well do a quick compression check and see where you're at; and if you had time a leak down.  If you knew base fuel pressure you could install a gauge and see if its making that?
Title: Re: MJ loss of power
Post by: Nick_Knipp on January 26, 2011, 04:21:08 PM
well im focusing on the whole fuel system now, ive already taken out the tank, fuel pump, sending unit, and both filters. im thinking of running an air compressor thru the fuel lines to clean them. the oil im puzzled about, i dont have any type of gauge to test any pressure.
Title: Re: MJ loss of power
Post by: S14unimog on January 26, 2011, 04:32:10 PM
^ well surely that can only help given the age of the lines on that MJ.  I don't understand what you're saying about the oil?
Title: Re: MJ loss of power
Post by: Nick_Knipp on January 26, 2011, 05:23:12 PM
oil

after driving a long time on the interstate it started to burst all over the head, theres even some on the hood (inside part) the 2 lines that were going into the head were loose when i checked, i plugged and taped them back on, couldnt do it 100% w/o tools. oil dipstick doesnt show much loss of oil, but it leaks really bad.
Title: Re: MJ loss of power
Post by: rabunjeeper on January 26, 2011, 05:56:23 PM
oil

after driving a long time on the interstate it started to burst all over the head, theres even some on the hood (inside part) the 2 lines that were going into the head were loose when i checked, i plugged and taped them back on, couldnt do it 100% w/o tools. oil dipstick doesnt show much loss of oil, but it leaks really bad.
I still think it has blow by and thats what caused it to blow oil everywhere.  I used to have an old nova that would do the same thing when i drove at high rpms down the freeway. Around town it never gave a problem.
Title: Re: MJ loss of power
Post by: DOUG on January 26, 2011, 06:46:04 PM
well im focusing on the whole fuel system now, ive already taken out the tank, fuel pump, sending unit, and both filters. im thinking of running an air compressor thru the fuel lines to clean them. the oil im puzzled about, i dont have any type of gauge to test any pressure.

Nick, sounds like the fuel issues will be handled, but I'm with the guys that say you have blow-by and a serious engine issue.  Do you understand what the guys mean by blow-by? 
Title: Re: MJ loss of power
Post by: Jimmy on January 26, 2011, 07:04:52 PM
Does your oil smell like gasoline? Oil on the air filter?

Might be time to start looking for a 4.0. They are everywhere and cheaper than a rebuild.
Title: Re: MJ loss of power
Post by: Nick_Knipp on January 26, 2011, 07:14:17 PM
honestly im new to mechanical terms, still learning in college. i dont know what a blow by is, i think its related to high pressure tho. and yeah im thinking of rebuilding the 2.5, and no i wont be looking for a 4.0, cause im gonna drop in a 5.9 in the future, why have to do 2 engine swaps?

the 2.5 is an okay engine, gets me where i need to go and pulls just fine for the truck, hell i pulled robins fishing boat with it

the entire truck needs to be worked on i know that, which is why i bought it  ;D
Title: Re: MJ loss of power
Post by: rabunjeeper on January 26, 2011, 07:46:05 PM
Blow by is where when the cylinder builds compression it leaks by the rings if they are worn out. That pressure that went by the rings goes into the crankcase where your oil is. SInce you have a sealed engine, the only escape for the pressure is out through the valve cover usually and anything that is connected to it will get blown off and oil will be all over the top of your motor. Another tell tell sign the rings are worn out is low power. Like I said earlier, crank it up and remove the oil fill cap and see if it is blowing some steam out of it. Then you will know.  {toast}
Title: Re: MJ loss of power
Post by: Nick_Knipp on January 26, 2011, 08:06:13 PM
alright ill have to check that when i install the fuel system again.
Title: Re: MJ loss of power
Post by: zukbilly on January 26, 2011, 08:24:14 PM
how about the cat being stopped up. I have seen it cause crankcase pressure before and sounds alot like what u say its doin
Title: Re: MJ loss of power
Post by: Jimmy on January 26, 2011, 08:40:43 PM
I think he would have noticed a glowing red cat by now if it was stopped up, but it is a possibility. I've seen a few catch on fire too, which probably would have happened on a trip to Atlanta and back if it was going to happen.
Title: Re: MJ loss of power
Post by: Nick_Knipp on January 31, 2011, 04:59:31 PM
just finished the fuel system, its clean as a whistle now.

next thing i did was check the oil fill cap and see if steam came out, nothing

i just think the vales are bad and need replacing. including the gasket (easy job)