13BT Overheated (1 Viewer)

[woody]

Still doing some diagnosing today, but we took the BJ74 down to Vegas on Saturday...got about 30 miles out and it overheated. Temp gauge was pegged, steam from the overflow. We were driving 70-75mph with a mild headwind on a cool-ish rainy NV day.

@Mace rescued us - THANKS!

System was "dry" and took 2 gallons of water. Drove it around Vegas on Sunday with no issues, checking the system regularly. Some quick searches led me to a likely solution - fan clutch...so that is already ordered and on it's way. ( @beno recommended)
http://www.amazon.com/Aisin-FCT-001...&redirect=true&ref_=oh_aui_detailpage_o00_s00

Will be doing a few other items while I'm in there as well...cap, thermostat, gasket for sure...also plan to pull the radiator just to check for any blockages.

We then chose to drive home last night...entire trip went well, took it a little easier on the climbs and was paying CLOSE attention to the factory temp gauge. Got to St George (100 miles) and the gauge dipped about 1/8", then instantly pegged. The fuel gauge pegged too! Quickly pulled over...no steam...hmmm...drove another mile to a gas station and pulled in. Overflow was gurgling, but no steam. Cap was hot. Had the heater cranked, blowing hot air. Top/inlet on the radiator was hot, balance of the radiator was very cool (felt the sides). Refired the truck, and gauges were back to normal. Opted to drive thru town for the last 15 miles...got about a mile down the road and the fuel/temp gauges again pegged! Pulled over again, no steam...opted to continue our drive home.

About 3 miles from the house, at 40mph, we still had the heater cranked and hot air blowing (if it's blowing hot air, there is still water circulating)...but it started cooling down, and within 1/2 mile was blowing cold. Pulled into another gas station to check everything over again. No steam, same felt-temps as before (hot cap, hot radiator inlet, cool radiator). Fuel/Temp gauges have stayed pegged. Sat in the lot for 10-15 minutes...still no steam. Fired the truck yet again, gauges returned to normal.

AGAIN decided to continue on for the last 2 miles...got half way, and the gauges pegged...and as we pulled into the driveway, the heat was beginning to blow hot again.

The gauge issue appears to be correctable, Temp Sending Unit? and I'll be looking more into that today. I'm wondering if there isn't "something" floating inside the cooling system that is blocking the heat valve, and causing other issues as well. All on today's exploratory list.

Thoughts and experience welcome

Quick details: stock 13BT, 200000km, a440...

 

[OGBeno]

Put a mechanical gauge into the thermostat fitting and run into your cab. You should have one anyway for the turbo.

And this is the classic 60 series gas/temp gauge issue as well.

That said, a good cooling system overhaul on a 25+ year old truck is not a bad idea.



Operators are standing by.

 

[Mace]

I called the Temp Gauge issue last night

That's about all the use I am other than on call tow rig and halfway house for LC addicts..

 

[Behemoth60]

Still doing some diagnosing today,

What you got there is a classic blown head gasket. Been there, done that, twice.

The factory gaskets in the 13BT are not good. They seem to be made of some fabric, and just disintegrate. The newer gaskets available from Toyota are a multi layer steel (MLS) style gasket, and they are incredibly good. The MLS 3B head gaskets are available in North America and are identical to the 13B-T units, so they should be available.

Hint, If you ran it dry, which you did if you put 8 liters of water in, then also replace the water pump. It's way easier to change it with the head off, than trying to replace it later, and it likely needs replacing now too.

Hint 2... there is some mystery interconnection between the temp gauge and fuel gauge. Some weird thing sometimes happens where when you are on a road trip, the fuel gauge stays at full, but the temp gauge goes up and up. Turn off the truck, and let the gauges reset to zero and turn it back on, and everything is back to normal. Weird, and I've never figured out why it does this.

Peter Straub

 

[Behemoth60]

One more thing, as the coolant level gets low, the heat output from the heater becomes intermittent as water does, then does not, get pumped to the heater core. Varying engine speed sometimes helps the pump get water flowing again. You have no problem with gauges or sending units. You have problems with inconsistent coolant levels, due to that aforementioned blown head gasket. The heater issues are a symptom, not the problem.

 

[Gun Runner 5]

The fuel gauge / water temp. gauge pegging is most likely a grounding issue. I'm fairly sure those two gauges share the same power source and ground.

 

[Behemoth60]

steam from the overflow.
We were driving 70-75mph with a mild headwind.
Overflow was gurgling, but no steam.

These are the dead give-away's of the head gasket problems. Cylendar gasses leak past the head gasket, into the coolant system, and blow your collant out the overflow bottle. Water levels get low, and you water pump becomes 'vapourlocked', and cannot pump the water up through the head.

Head blows on long hard pushes... i.e. into that head wind. These are the exact symptoms I've had on my 3 blown head gaskets... a turbo'd 3B, and two 13B-T's. Each time, they engine had one of the original factory 'fabric' gaskets, on in the case of my 3B, an aftermarket fabric gasket. Install the factory MLS steel gasket, and since pushed those engines as hard as I could and never had a problem.

If this was a 3B with a factory head, you would have cracked the head for sure. 13B'T's are tougher, but when you have the head off, check very closely between the valve openings for cracks. It' possible the head is cracked, and that's where it would have cracked. Neither of my 13BT's had cracks, despite running dry under full power. With luck, neither is yours.
-Peter

 

[woody]

I'd be convinced of a head gasket if it overheated during the 120 mile drive on Sunday...more uphill elevation changes, similar temps and weather, similar speeds. We made a few stops to check everything, and noted no issues. I checked coolant this morning and added less than a quart, likely from that air-bubble that caused the heat loss. Allowed it to idle for a hour this morning and the heater blew hot. Engine oil was changed on Saturday and is perfect. What came out of the radiator as I pulled it was clean and clear. Insides of hoses are all fine as well.

Have the radiator out now to be checked, and awaiting a handful of parts from @beno to arrive. New temp gauge will be on the short list too.

Finding a radiator shop that actually checks radiators might be a challenge...have called 3, none "service" in this area, just replace. One last one had no answer, but suspect they are my best bet. These are obviously now "throwaway" items...dumb.

 

[Mace]

There is a couple down here that will still rebuild a radiator. Depending on your time table of course.

Most replacement radiators are now cheaper than rebuilding one. go figure..

 

[woody]

Install the factory MLS steel gasket, and since pushed those engines as hard as I could and never had a problem.

Just for fun, I ordered the updated head gasket as well...and a water pump...oh joy...

 

[ozcrusier]

The fun is just beginning seeing your pulling the head might as well get the injectors tested and have the valves and seats recut while your in there... oh the joy of it all.

 

[Behemoth60]

seeing your pulling the head might as well...

...polish the intake and exhaust ports. I did this on Ziplock's 13B-T when it had it's blown head gasket. Performance improvement is pretty significant. With a stock turbo pushing 21lbs, 2.5" straight pipes, and some decent head work, that truck easily pushes 40" tires down the highway at 125kmph with RTT and 7000lbs curb weight with EGT's below 1100f. And has been doing so for years.

Peter Straub

 

[Tapage]

...polish the intake and exhaust ports. I did this on Ziplock's 13B-T when it had it's blown head gasket. Performance improvement is pretty significant. With a stock turbo pushing 21lbs, 2.5" straight pipes, and some decent head work, that truck easily pushes 40" tires down the highway at 125kmph with RTT and 7000lbs curb weight with EGT's below 1100f. And has been doing so for years.

Peter Straub

With an A440 ..?

 

[Gun Runner 5]

Just curious, in relation to the radiator, is the heater core located in a high or low position on the BJ74?

 

[JuanJ]

Hello,

Engine Watchdog from eBay Australia is your friend.

I agree on the gasket. I also agree on the grounding, whether from a loose connection or a grounding point added by the PO or some mechanic over the years. How fast does your engine fire up?

Last but not least, allowing the turbo to "unwind" and the engine to cool down after long drives and/or sustained speeds over 90 km/h (55 mph) helps as well.

Hope this helps.





Juan

 

[woody]

Thermostat...old was likely original and junk (stove tested)...new one fixed the issue and it runs normally now

I've GOT the other parts in hand for a HG down the road...will monitor closely and dive in deeper down the road if needed.

 

[SeanBJ74]

Thermostat...old was likely original and junk (stove tested)...new one fixed the issue and it runs normally now

I've GOT the other parts in hand for a HG down the road...will monitor closely and dive in deeper down the road if needed.

What thermostat did you get ?

 

[FJBen]

What thermostat did you get ?

I got an OEM Toyota 88C thermostat. They are cheap and seem to work great.