4 Wheel Drive/SUVs/Overheating 89

Advertisement

Expert: - 2/7/2005


Question
My brother has a 89 laredo limited with 4L engine and he's facing overheating problems to the point that it spits out all the antifreeze from the bottle. This seems to be a common problem in these closed circuit systems. Any hints or recommendations other than converting to an open circuit system?

Answer
Peter,

Actually, the closed system is a fairly dependable system.  Normally, any heating problems with this system, can occur in a standard cooling system also.  The only problems that I have seen that are directly connected with the closed system, is the reservoir can become brittle and cracked, leaking off pressure and fluid.  In this case, you simply replace the plastic reservoir, and it's quite easy to replace.  

There are several other problems that can cause over heating.  I would start out by flushing out the radiator with a good commercial flush to make sure that all the radiator tubes are clear, and have proper flow.  You should check the cap to make sure that it's maintaining the right pressure.  Any radiator shop can do this for you.  You may need to replace the thermostat, as it may be sticking, or not opening properly.  A slipping fan belt can be another problem.  A bad fan clutch, or faulty electric fan, are a couple more common problems.  Another item that could be bad, is the water pump itself.

Most of these items are fairly inexpensive, and easy to replace yourself.  The hardest to replace, and most expensive (other than the radiator), would be the water pump.

Carl

4 Wheel Drive/SUVs

All Answers

Answers by Expert:

Ask Experts

Volunteer

Carl Brandt

Expertise

Will discuss suspensions, lifts, lockers along with tire suggestions. Trail ratings and possible requirements needed for specific type of trails. Safety equipment and what you should carry with you. Certified off-road instructor. I am not a mechanic, and 4-Wheeling is a hobby, so if I can't answer a technical question it is due to my mechanical knowledge being related to vehicles that I have owned, or have worked on. I do not have manuals on all vehicles.

Experience

40 plus years of 4 wheeling in a variety of vehicles. At the present time, my major off-road rig is a 94 Jeep Wrangler with a spring over and a 1 1/2" suspension lift. This gives me a total lift of 7" or so. I have lockers front and rear. I have removed the track bars, and sway bar for maximum articulation. I am running a stock 2.5 ltr 4 cylinder with a Jacobs ignition along with a cold air high flow filter. It has 4.56:1 gears with a Dodge NV4500 transmission along with a 3.8:1 Atlas II transfer case. This gives me a final ratio of 105:1 in low gear/low range. Other vehicles I own, are a 96 Ford F-250 with a 6" lift, posi rear end, 36" Hummer tires, 5 speed with a fuel injected 460 ci engine, an 87 Samurai with an 8" lift, Ford 9" rear end with a spool, Chevy Dana 44 front end with an electric locker, 5.88 gears, 16% reduction in high range and a 6.5:1 low range with 35" Baja Claws, and a stock 2003 Grand Cherokee Overland. Trails I have run are the Rubicon (10 times), Dusey Ershim, Fordyce Creek trail, McGrew trail, several trails in Moab, Utah along with local monthly runs.

Organizations
Lost Coast 4x4's Cal 4-Wheel Corva UFWDA Blue Ribbon Coalition

Education/Credentials
Certified off-road instructor - Certificates in engineering/electronics

©2012 About.com, a part of The New York Times Company. All rights reserved.