1. Home
  2. Ford Trucks
  3. F-150 low on coolant - common causes?

F-150 low on coolant - common causes?

Hi all,

just got back from looking at the F-150 that I posted about earlier...

good: straight, rust free body, only surface rust on frame and driveshaft. Could easily be detailed underneath in a couple weekends. Only cosmetic issue is a slightly tweaked rear bumper, apparently caused by towing a trailer from the step bumper and not having a proper receiver hitch installed.

meh: lots of oil leaks, although it was still full of oil. All fluids seem to be old, and I think it needs new front shocks and probably wheel bearings (slight hum from front end, although that might be the tires, which were a little low from sitting for several months. Also a rattle, but the leading arm bushings looked OK at a visual, although obviously since I was laying on the ground looking at it with my trusty Mag-Lite I couldn't jack it up and wiggle stuff.) Transmission a little slow to engage from a cold start at ~30 degrees F, but it did engage solidly. At about 130K miles I definitely think it's due for a full fluid change and bearing repack at a minimum. However, I have tools, and am used to the "barn car" change/regrease drill.

bad: A/C is inop, my guess is that all the freon leaked out of the receiver/dryer as it is pretty rusty and there's some very minor oil spotting on the inner fender below it. Also, and this is why I didn't come home with a title in my pocket, the radiator was only about half full.

So what in the experience of those familiar with these vehicles is the common cause of coolant loss? Water pump? Head gasket? Other? This is a 300ci straight six, 93 model year. Also, is it possible that it is too cold for the A/C to engage? Is there some kind of low temp interlock?

Oh- one more question comes to mind. The oil pressure gauge was solidly in the middle even after I let the engine get a little warm (I only drove it around the block a couple times because I didn't want to get it real hot with the coolant so low) I assume this is good, but is this a gauge, or an idiot light with a needle?

I'm kinda half-assed tempted to offer to pay to have the coolant issue checked out, because I still like the truck. For 14 years old, it looks damn good albeit plain, and I'd rather have a straight rust free body than lots of accessories to break - I'm just looking for a good, basic work truck.

any opinions appreciated... I know I'm being picky about a 14 year old beater truck, but the truth is I already have three cars that are giving me fits, and the whole purpose of this exercise is to get something that doesn't need any major work.

thanks,

nate

Reply to
Nate Nagel
Loading thread data ...

On Tue, 06 Mar 2007 20:09:38 -0500, Nate Nagel rearranged some electrons to form:

The oil pressure gauge is ...

Reply to
David M
300 not known for head gasket or cracked head issues. could be water pump, easy change, top tank on the rad, bad cap.

Whitelightning

Reply to
Whitelightning

beater? It's nearly new! Well compaired to my '81 anyway. Mine isn't a beater....in fact I'm going to have it repainted very soon! 26yrs and the paint is going bad already.....

The AC compressor will not engage when the ambient temp is

55=B0(give/take =B0's)

Most common causes for coolant loss are old hose/hose clamps. Heater cores don't last much past 10yrs. Check below the water-pump for signs of 'weeping'. The radiator might also have some 'weeping'. Look for signs of that on the engine side of the rad. A new radiator cap is a good maintenance item replacement.

Install a mechanical oil-pressure gauge(copper pipe feed, NOT the plastic pipe feed). Look on the auctions sites for the Ford factory service manual for your truck. Not a chiltons/haynes 'repair' manual. The FSM will be a great help to you. A little maintenance/TLC will keep your almost new truck going for a long time...

Dave S(Texas)

Reply to
putt

Last year I finally got rid of my 1992 F150 with the 300 six and the E4OD transmission. In later years I had a problem with coolant leaking. It was the hoses. Look for white residue around the hose clamps. My truck still had all the original hoses and water pump. I never had any oil leaks, so I was surprised by you comments about oil leaks. I sold the truck after my son managed to do something bad to the transmission, The truck was 14 years old, and I wanted to replace it, so when the transmission acted up, I sold it for $900. The guy that bough it had a local mechanic open up the transmission. It turned out to cost him just $500 to get it fixed. So he got a good deal, but he did take a risk on the transmission.

If the one you are looking at is a 300 six, it could have either the E4OD or the AOD. My E4OD did exhibit the "slow to engage" characteristic that you mentioned. On the other hand, it exhibited it for 10 years with no problems. I had one other weird thing happen with the transmission. When it was relatively new (50,000 miles) I was driving around in a plowed field on a very very hot day. For some reason the transmission started pushing fluid out the front seal. I was sure I had roasted it, but my mechanic advised me to let it cool down and add fluid. Sure enough, it worked OK and I never had that problem again. It is my understanding that early E4ODs could get in a mode where they over heated and this caused something to stick internally which allowed the pressure to build up to the point where they would force fluid out of the front main seal. My truck did not have an external transmission cooler, which probably was a contributing factor (my truck was a stripper). Ford issued a TSB recommending the installation of an external transmission cooler for trucks like mine that were in severe service. I guess driving around in a plowed field in July was severe service :).

I have no idea how the AOD transmission stacked up to the early E4ODs. I know that later E4ODs were much more robust. Other than the transmission concerns, my F150 was great. I had to replace the alternator and fuel pump when the truck was about 13 years old. The fuel pump didn't fail, but the check valve that is part of the pump quit holding pressure when the truck sat for a few days, making it difficult to start sometimes.

Ed

Reply to
C. E. White

Follow up... the PO had the truck inspected and it passed; he filled it up with coolant and asked the shop that did the inspection to pressure test the cooling system and according to them it tested OK. Should I still be considering this truck? Or is the engine "fragile" enough that having been run for a few miles low on coolant would be terminal?

I'm still tempted to buy it as the body is in excellent shape, as is the interior.

nate

Reply to
N8N

The 300cid is bullet-proof. Low coolant level would have no effect. I have a story about_no_oil....

Dave S(Texas)

Reply to
putt

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.