Mystery water loss

[odeek9]

Hi-After owning this truck for 29-30 years one would think I wouldn't ask such a stupid question but here I am. Before I take it to a garage maybe someone can help me.
Beginning a few days ago I began noticing the coolant level in the reservoir was going down about an inch each day. Yesterday following an 80 mi. trip it had lost 1/2 of the coolant level only in the reservoir. I cannot find a leaking hose anywhere. From beneath there is a drip to a slight stream coming from somewhere between the engine and clutch housing. There's a thin metal plate there which it drips from. I can also see a bit from above at the back end of the area just below the valve cover. But it's inaccessible for me. And I can't find the drips origin! No oil in the coolant-no coolant in the oil. Truck runs fine except for a new rattle coming from the fan/radiator area that happens only for the first couple of minutes after starting. Belt is tight as are all pulleys. The truck never runs above 170.
Worried about the worst (cracked block or head gasket problem) I did a compression test and it's as always, 180-190 for all 4 cylinders. Is there any coolant that runs into the bell housing that could leak coolant internally that finally finds its way out? I don't think so but I'm no mechanic. Any thoughts PLEASE?
Thanks so much

 

[Mark_88]

If you are not getting a smoke trail out of the tail pipe with that much fluid loss then it is dripping maybe from the weep hole on the water pump...or somewhere else.

A quick test is to remove the rad cap with the engine cold...put a rubber glove over the rad opening and secure it...start the engine and watch the glove. If it blows up then you probably have a leaking head gasket...

If that doesn't work or apply try these suggestions...

https://www.youtube.com/watch?v=5zpNjYmmiYY

 

[Doofy]

Does sound like either a head gasket or possibly a rear core plug that has developed a pin-hole leak due to corrosion.

 

[tomw]

Two things came to mind. The first is the custom hose that goes from the tee in the heater hose around the back of the cylinder head and into the bottom of the intake manifold. Mine, '85, has one. Yours, a year later, likely also has one.
The second thing is a freeze plug on the block or back of the head. If the coolant is above the top line of the bell housing, if it is a freeze plug, it is very likely it is in the back of the head. If below, the back of the block.
Have you maintained the coolant/anti-freeze in good condition? If not, the coolant may have allowed the plug to rust through. If you have changed the coolant upon occasion, and refrained from adding water, diluting the coolant protection, is is more likely it is the hose. A section of good hose can take the place of the formed hose and should handle the task readily. IOW, you don't have to chase down a custom shaped hose if yours has failed. If it is too difficult, a section of hose could be cut out, and replaced with some metal tubing of the proper diameter using a couple screw-type hoses.
tom

 

[odeek9]

mystery water loss

Two things came to mind. The first is the custom hose that goes from the tee in the heater hose around the back of the cylinder head and into the bottom of the intake manifold. Mine, '85, has one. Yours, a year later, likely also has one.
The second thing is a freeze plug on the block or back of the head. If the coolant is above the top line of the bell housing, if it is a freeze plug, it is very likely it is in the back of the head. If below, the back of the block.
Have you maintained the coolant/anti-freeze in good condition? If not, the coolant may have allowed the plug to rust through. If you have changed the coolant upon occasion, and refrained from adding water, diluting the coolant protection, is is more likely it is the hose. A section of good hose can take the place of the formed hose and should handle the task readily. IOW, you don't have to chase down a custom shaped hose if yours has failed. If it is too difficult, a section of hose could be cut out, and replaced with some metal tubing of the proper diameter using a couple screw-type hoses.
tom

Thanks for all of the replies-I'll check those possibilities out today. Sorry for the late response as the email notification didn't work

 

[odeek9]

Thanks for all of the replies-I'll check those possibilities out today. Sorry for the late response as the email notification didn't work

Just to let those who helped me know that it turned out to be a small hole in a hose hidden behind the valve cover. The garage had to place pressure through the system before even they could find it. They replaced it along with giving me a couple of hi temp hoses. $100 which isn't too bad. I guess it's to be expected with a 30 year old truck-it won't be the last time as a gazillion small things will begin to fail. Thanks again for your thoughts!

 

[Doofy]

Thanks for posting the solution and am glad you got it fixed!

 

[Mark_88]

Yes, thank you for the update and congrats on the fix...even though it was a garage that did it you acted on it appropriately and that's all that really matters. I cracked two heads on my Ranger by overheating them so I know how serious it is to keep the cooling system in top shape.

I cannot express enough how a bit of maintenance and checking things can pay off big time in the long run...but it sounds like you are familiar with that so always a good thing...

 

[odeek9]

Thanks to both of you. I'm in my 60's now- just unreal - and just had open heart surgery a few months ago & really am limited in what I can do. Anyway, the only garage out here is $130 pr/hr but he usually gives me a break so I can't complain too much.

I've always paid a great deal of attention to oil and water-you just have to. Funny thing is that somewhere during this process today the mechanical temp gauge conked out-lines probably jostled about. So tomorrow I get to get dirty and install the new one. Question is: what will fall apart when doing this? Old truck and a mechanic I'm NOT!

 

[Mark_88]

Haha...oil and water is exactly the main thing to keep an eye on. I usually had a problem with keeping the gas in the tank and the fuel pump I hooked to my carb but that is another long story.

I hope the recovery from the surgery is going well and you are back at it before too long. I spent a month in a rehab hospital with a few guys who had heart surgery and I was amazed at how fast they were up and walking around like nothing happened. Yours must have had some complications but take your time and keep working at what you can do.

On these trucks there should be either one sensor and one sending unit or both. This was before the computer took temp into consideration (I think) so you probably just have the sending unit. They are either on the driver side of the block or may be on the intake near where the hose connects that was leaking so likely got jostled like you say.

The one on my 88 had two wires running from the sending unit on the intake but that was a carbureted truck so not really sure what the fuel injected units have.

Tomw would probably know better since his truck is closer to yours and maybe he can elaborate on that better than I could.

 

[odeek9]

Oh I'll be fine. The operation was more involved than I had anticipated and the stay in the hospital was longer than the norm. It all came as a surprise but it was one of the prices one pays for a life of sin, lol.

I first installed the mechanical gauge a very long time ago. I didn't trust the stock electrical unit. I don't recall much difficulty-threading in the sensor, running the cable to the gauge, grounding the gauge and the light lead to the fuse panel.The part has been ordered and will arrive tomorrow. I'll just crawl around in the dirt and be done with it without any complications hopefully. Unless I find myself at an impasse I won't be going to the mechanic-too poor in my old age (speaking of which how in the Hell did that happen?) I hope it's an easy day!

 

[Mark_88]

Oh, sorry, missed the fact that you replaced the original with a manual gauge. Not really familiar with those so out of my league so to speak. Sounds like you are on top of this too so if you are capable of crawling around under the truck you are in better shape than I imagined...which is a good thing.

As to how you found yourself old and broke...lol...I'm wondering the same thing but not too much. Most of my life I was one paycheck away from poverty and I was never married or raising kids so I always wondered how families could survive...

One of life's little mysteries to me...

 

[Doofy]

I too am a member of "The Old Farts Club". I think we all suffer from the RipVanWinkle Complex...went to bed young and woke up old! Haha

Memory sucks, hard to pee, hair falls off head and then sprouts on back and shoulders, fall asleep while working under truck and then can't hardly stand back up after crawling back out. Ailments are many, numerous pills but the print has gotten so small on the bottle you can't read it.

There have been Good Times and Bad Times, Happy and Sad Times and for the most part...it has all been worth it.

 

[Mark_88]

haha...

I was considering taking up Origami, the Japanese art of folding paper into animal shapes...but then I found myself calling it "Fold Art for Old Farts"...and decided to find something else for a hobby.

 

[Doofy]

Certainly is hard finding a decent hobby. I recently bought a .177 pellet pistol for taking out Tree Rats (squirrels) stealthily and as quietly as possible as the neighbors are squirrel lovers. Even the subsonic .22s and bird shot are just to loud.

Anyway, having an absolute blast. Since vision is dim and fuzzy I mounted a reflex red-dot sight on it and made a cardboard target holder out of 10 layers of cardboard and now I can plink away in the garage and hone my sniper skills. Took out 4 rats last evening and now I see 7 or 8 more out there scaring the birds.