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Topic: 89 Ford 350 running hot (Read 152 times) previous topic - next topic
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89 Ford 350 running hot
Hi, questions for owners/technicians of older LDs. I’m a new owner of an 89 M23 with a Ford E350 and it seems like the engine is running hot. It’s fine idling, but when we bring it up to speed on the highway like 60-65mph the heat creeps up pretty quickly, like the top of normal range. Flat road, with or without a/c on. Looks like the oil pressure is a little low too, but still within “normal”. Is this normal? My mechanic is starting to check things like thermostat, radiator fan, but says it’s not unusual for older American trucks to act like that. I noticed around 65mph the LD feels maxed, which makes me wonder. Is there maybe a transmission issue here? I also did a search here and read a post 12 years ago that mentioned the 350 is weak so I’m wondering if this is just the result of an underpowered engine working too hard. If it’s not normal and you experienced it what ended up being the issue?  Thanks
 
Re: 89 Ford 350 running hot
Reply #1 –
Have the mechanics check for a plugged exhaust system.
Dave 04 Excel
2004 PleasureWay TD
Re: 89 Ford 350 running hot
Reply #3 –
Hi G Bert;  Welcome to the Group!   If this is a Ford Chassis, you have an Econoline Van cutaway chassis  E350 with either a 355 C.I.D.  (5.8 liter)  V8 engine, or the larger 460 Cubic Inch Displacement sized engine. Also a V8 (7.6 liter displacement) Neither engine should overheat.  I would suspect a partially plugged up radiator. Or a fan clutch problem. No catalytic converter to plug up, although there could be some other blockage in the exhaust system.  Timing off, and many other problems can cause slight overheating.  Make sure you have enough oil in both the transmission, and the engine. A water temperature gauge would help here also. You don't say where in the country you are located.  It has been hot as usual, in August, in Southern California.
    The 350 referenced being 'weak' I believe was the GM 350 cid engine.   Ford did have many problems with exhaust manifolds breaking.  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: 89 Ford 350 running hot
Reply #4 –
-Plugged or undersized radiator. Defective fan clutch. Slipping fan belt, worn water pump impeller. Plugged or dirty engine water passages. Bad head gaskets. Internal engine damage.
-Engine out of tune or running too lean.
-A plugged catalytic converter, yes it has one according to Rock Auto.
Your mechanic can do an exhaust pressure test, a vacuum gauge can sometimes also be used to determine a plugged exhaust.
1989 FORD E-350 5.8L 351cid V8 Catalytic Converter | RockAuto

Other possibilities.
-Dragging brakes
-Transmission problems that produce excessive heat with slipping plates and/or clutches.

For all rigs, adding a bigger transmission cooler isn't a bad idea.
Larger transmission cooler E450 | Flickr

On both of our LDs, an added water spray system has been installed to cool the radiator and transmission under high heat conditions when climbing steep grades. It works well.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: 89 Ford 350 running hot
Reply #5 –
Thanks Larry; I was relying on memory about the cat converter on a 1989, so that would be a likely suspect. 
    I assume that the mechanic or someone else did a smog test to transfer title.  Probably just an OBDI on a throttle body injector back then.  And I would weigh the vehicle also to see if the 11,500# weight limit has been exceeded.  Just a straight 3 speed transmission.  Also check wheel alignment, and air flow around the radiator to make sure that baffles meant to direct air through the radiator are still in place. So many possibilities to check!   RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB