Coolant leak?

[TexasRoach]

As I come before the Mud Oracle I'll preface with I'm a noob, a new owner and have very little automotive acumen...

So I've driven around town a little over the last 4-6 weeks since bringing the beast home. Longest trip has been about 25-30 miles each way averaging about 40-50 mph and that round trip was separated by about 1 hour of cooling. When I got back to the truck for the drive home on that trip I noticed a LOT of water had leaked out. It seemed to run fine until I was almost home and it looked like the thing was going to overheat. Additionally, I noticed the oil needle was riding really low. Was a good bit of idling in construction traffic and temps/humidity were Houston standard conditions...95 and high. Here is a photo of roughly the needle positions at that time (red lines).

So once I got out the oven mitts and opened the hood to cool it down for a few hours I checked and couldn't see any water or coolant. I topped it off and today I made a 3-5 mile drive after which, immediately after I parked, it started leaking out lots of coolant. Didn't notice any significantly high or low needles but it was a short trip. Locations I could see it collect are circled.

Sooo...Did I just overfill the reservoir? Is the radiator too small for this small block Chevy 350 (if so, recommendations please)? Is the fan too small (and lack of shroud)? Bits and pieces of all? Other?

Here are a couple other reference photos if it helps diagnose the issue.

As always, thanks gents.

 

[TexasRoach]

And here's another photo.

 

[middlecalf]

First step is your coolant system needs a serious flush. That pic with the cap removed shows a gunky mess. Flushing would need to include the heater system and coil/coils as well as the entire engine cooling jacket. If that is successful in clearing out the gunk jam, then I’d definitely look into getting a fan shroud. That might have to be custom (mine was for my 283SBC). The flush will determine if your radiator is still useable.

Oh, and you’re out of fuel.

 

[TexasRoach]

Yeah @middlecalf that gunk is not helping the situation and the flush/fill will go to the top of the list. Thanks.

 

[ToyotaMatt]

IMO ,

based strictly off the photos and the facts provided @by @TexasRoach


The GM small block , if thats what it is ? im not a DETROIT info source in any way

has either Blow a Head Gasket , or cracked a Block or Head Water jacket type issue

in addition to lack of coolant being consumed by the engine and also the external Leak ,

has caused the Overheat issue

also Super heated Combustion gasses Are entering the Cooling system most likley as well

the Dark Chocolate Milk-Shake appearance of the engine coolant is NOT natural in any way shape or form


i would start By Pulling all 8 spark plugs and performing a Comprehensive Engine Compression Test

, that will tell u real fast if 1 or More Cylinders has Failed in Some way Like i Suspect has Happened

I hope im wrong , but the Text Book Fundamental Internal Combustion Engine Facts above don;t Lie ....................

 

[TexasRoach]

@RAGINGMATT well...damn.

Should I bother with the flush at this point or would you recommend the compression test first?

 

[middlecalf]

What does your oil look like? Matt is right, something is amuck.

You can do the compression test (and a leak down test) before the flush. But if the engine will stay in your future (in any case) it needs to be flushed.

 

[TexasRoach]

I was going to go ahead with the flush since I already got all the stuff to do it and when I tried to drain the radiator I found the drain screw to be pretty well stuck. I was afraid to torque on the thing too hard for fear of snapping the damn thing off. When I first brought it home I took the rig to my mechanic to give it a good once-over. Oil change, new plugs, new fuel filters, etc. Also on that list was a flush and fill. This was just over a month ago, so either what I'm looking at ain't the radiator drain or I don't see how the hell they did a proper flush. I called them and the mechanic that worked on it confirmed that yeah, he did the flush and fill, so I'm going to bring it back tomorrow and have them explain to me how the hell they did it.

Here's what I was assuming was the drain plug. Best photo I could get trying to juggle the phone and the shop light from under the truck.

 

[brian]

That's the rad drain.

 

[4x4veteran]

I am repeating but have you checked the dip stick and the breather cap?
Is there any tan froth on either?
I would pull the radiator so I could get at the drain better and clean the insides.
If you have a big enough tub that the radiator in you could block the inlet and outlet and pressure test for leaks.
It only need 10 psi or so.
Unless you have a radiator repair shop close.
They are nonexistent around here.

 

[TexasRoach]

That's the rad drain.

Ok, well I'm not a total moron.

 

[3_puppies]

2 things, if you are draining the rad use 2 wrenches, don't just try and loosen the lower one without holding the long tube with another wrench, you will just twist the tube out of the bottom of the rad.

when you get the engine issue figured out, you will need a fan shroud.

 

[TexasRoach]

if you are draining the rad use 2 wrenches, don't just try and loosen the lower one without holding the long tube with another wrench, you will just twist the tube out of the bottom of the rad.

Im SO glad you said that. I was just wondering about that a few minutes ago.

Thanks!

 

[ToyotaMatt]

@RAGINGMATT well...damn.

Should I bother with the flush at this point or would you recommend the compression test first?

I would simply do the compression test first ,

heres why ;,

- its Free / does not cost parts or labor

- it rules out alot , and may yield new unknown Test spec. data Info ?

- it makes your path foward a bit more clear and direct / concise

@3_puppies is correct , use extreme caution removing that Rad Draintube pet cock , practice a dry run approach before going at it

i Rung one clean off as a teenager on my 12/78 and it took little to no force , u need the 2 wrench approach

a New CSF Brand all brass radiator is over $500 now , i was shocked to find thats out a few months ago



- u can aslo examine your 8 spark plugs using the toyota FSM as a guide book , if u have a blown head gasket or cracked engine block water jacket , one or more of your plugs WILL look different , and have a Bright Snow white and cleaner appearance then the rest

- the amount of " SLUDGE " in your Radiator cap Filler Neck IMO , is over the threshold of anything natural occurring ,

But, first DO look at your OIL cap , & Briether for a Milky whitish Oily Sludge collection points , this is SOLID Information gathering

- Sorry this is happening , but the TEXT-BOOK approach is wise to follow till u Diagnose things Fully

- the last thing u want is to a Cause More damage buy accident or UN-knowingly if u follow me .....?

 

[3_puppies]

a New CSF Brand all brass radiator is over $500 now , i was shocked to find that out a few months ago

is the rad NLA from Toyota? I thought Toyota was under $400?? 16400-49356 that is for a 4 row, I think.

 

[ToyotaMatt]

Im SO glad you said that. I was just wondering about that a few minutes ago.

Thanks!

i found a Link to Your Exact path forward , its pretty good solid info : there 's 3 pages TOTAL , i just read the entire Article

https://troubleshootmyvehicle.com/gm/4.3L-5.0L-5.7L/how-to-test-for-a-blown-head-gasket-1

Part 2 -Troubleshooting a Blown Head Gasket (GM 4.3L, 5.0L, 5.7L)

Page 2 of 3: Troubleshooting a Blown Head Gasket (GM 4.3L, 5.0L, 5.7L). TEST 2: Engine Compression -Exhaust Gases Coming out of the Radiator. Coolant shooting out of an open radiator.

troubleshootmyvehicle.com

Troubleshooting A Blown Head Gasket (GM 4.3L, 5.0L, 5.7L)

How to test for a Blown Head Gasket. GM 4.3L, 5.0L, 5.0L. Symptoms of Blown Head Gasket. 3 Easy tests. Testing A Blown Head Gasket.

troubleshootmyvehicle.com

 

[TexasRoach]

Y’all are awesome. Thanks a ton. Guess I know what I’m doing tomorrow.

 

[ToyotaMatt]

is the rad NLA from Toyota? I thought Toyota was under $400?? 16400-49356 that is for a 4 row, I think.

City Racer has OEM FJ40 2F Radiators Currently Available for exactly the Price point you Mentioned , i just checked

it comes with a 16401-42021 Cap Too , those run $25 MSRP from TOYOTA now .........

OEM 2F Radiator for Land Cruiser FJ40

Toyota OEM radiator. Fits all years of Land Cruiser FJ40 with 2F egine and without factory A/C. 4 core. Includes radiator cap and drain plug extension. Shipping notes: Due to Toyota factory packing being insufficient for transport, the factory box will be repacked by us with additional...

www.cityracerllc.com

 

[TexasRoach]

@RAGINGMATT

Test 1 complete. This looks like normal oil color and viscosity to me. Whatcha' think?

Test 2 to follow...stay tuned.

 

[TexasRoach]

Test 2 complete...no geyser of coolant.

Plan going forward is to try to get that drain plug loose and do the flush. I will still take it for a compression test to be sure though.

Is it possible that because Dad had it sitting for so long putting no more than about a dozen miles per year on it for who knows how long that there was just an incredible amount of gunk to clear out...more than a single flush would fix?