Cruiser Down: Tale of Heater T failure on a 100 series (3 Viewers)

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Joined
Dec 26, 2020
Threads
5
Messages
69
Location
Monterey, CA
As an intro, I’ve got a 1999 cruiser (had an 1997 80 previously). Rust free, California vehicle. Just turned over 200k a few days ago while in Yellowstone. Beautiful cruiser, but spotty maintenance records.

This weekend (Saturday, 7/17/2021) we visited Mount Rushmore as part of our great American road trip with my wife and 2 sons (I’m Navy and being transferred from CA to DC area). We’ve had great performance with the cruiser through Zion, Bryce, Yosemite, Sequoia, Flagstaff, Yellowstone, Death Valley, and places along the way.

While going through a stretch of up-and-down switch-back turns in Custer State Park in South Dakota, I heard a noise from the motor and glanced down to my scan gauge FWT reading— 283! (For context, through Death Valley a week ago, I saw 206 max). The check engine light came on and I turned off the A/C and eventually the motor a few seconds later. At the turnout that was luckily there (with a great cell signal, fortunately), I popped the hood. The motor was steaming but no sign of coolant… also, plenty of coolant in the overflow tank.

I had some water in a portable camping shower tank we were carrying so I sprayed the motor to cool it down a bit (I was actually concerned about a fire at first). Then, I could see coolant flowing (as if being washed down) from below the vehicle.

We got a tow back to Rapid City to the Toyota dealer (thanks to USAA, but, oddly, the nearest contracted roll-back came from Sturgis — 2 hours away).

Yesterday, while stuck here in Rapid City, I went and dumped some coolant and water in it to try and do a bit of diagnosing. It didn’t leak unless I started the motor. No white smoke. No coolant in oil. No “milkshake”. No spraying up on the hood insulation. I let it sit and waited until the service team opened this morning, lest I cause more damage.

my initial thoughts based on some ‘mud research was a failed or botched-install water pump. The timing belt and water pump were done at 196k — just prior to my purchase (it’s one of the few receipts I have of the cruiser’s history).

This morning (Monday), the service team here in Rapid City said… heater T. It was a busted heater T. So, tomorrow (hopefully), with fresh Ts, a coolant flush and some Toyota “red”, and an oil change, we can get on with it and continue east. Can’t happen soon enough — cheapest hotel in Rapid City is $300 a night (this post COVID price gauging needs to settle down. Although, next month’s bike rally in Sturgis and tourist season at Rushmore doesn’t help, either).

I had a thorough check over done before I left CA but I suppose that “multi point inspection” didn’t cover what it needed to. Such is life.

I’m curious of your thoughts or experience with such failure. There’s some posts on the forum, but I wanted to share my story. I think I’m lucky — or at least it seems so at this point — that I didn’t get the dreaded head gasket failure or worse.
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It's an extremely common and well-documented failure in the 100 series, unfortunately. Glad you got out of it with minimal long term damage.

I got stranded with a dead alternator coming back from Mt Rushmore a couple years back. That area of the west doesn't seem to like 100's on road trips too much...

Welcome! Nice 100!
 
It's an extremely common and well-documented failure in the 100 series, unfortunately. Glad you got out of it with minimal long term damage.

I got stranded with a dead alternator coming back from Mt Rushmore a couple years back. That area of the west doesn't seem to like 100's on road trips too much...

Welcome! Nice 100!
Thank you, friend. Glad yours worked out, too! And it’s definitely the “Wild West” out here for getting a fix.
 
Hoping the best for you and that great looking LC! Let this be a warning to those who haven't changed out their T's -- it's a very easy job, do it now!
 
Glad you can resume without major damage.

PSA for everyone, don’t delay:

 
Glad you can resume without major damage.

PSA for everyone, don’t delay:

Yes! Good reminder. It’s something that must be kept up with… or, you can vacation in scenic Rapid City 🙄
 
Good lookin truck, hopefully you caught it in time before any permanent damage.

I carry 2 heater t's and a spare coil pack in my truck at all times. These things are tanks but the smallest things can chop them down if overlooked.
 
Good lookin truck, hopefully you caught it in time before any permanent damage.

I carry 2 heater t's and a spare coil pack in my truck at all times. These things are tanks but the smallest things can chop them down if overlooked.
Wise man. Wise.
 
I was fortunate....while replacing my starter I just BARELY bumped the heater hose with the intake manifold and one of the heater Tee's snapped right in two. I replaced with metal Tee's. It is in fact a quite common issue if they've never been replaced. Glad you got back on the road.

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A couple of 3/4" bolts and worm gear clamps (and maybe some teflon tape) and you can plug the hoses and be back on the road (no heater though). Or a section of longer hose and just connect the two pipes coming out of the engine block.
 
I heard a noise from the motor and glanced down to my scan gauge FWT reading— 283!
Unfortunately, I would be very surprised if you don’t have a HG leak. I hope you don’t, but at 283*F, it should be blown. Did the dealer do compression or leak down tests?
 
Unfortunately, I would be very surprised if you don’t have a HG leak. I hope you don’t, but at 283*F, it should be blown. Did the dealer do compression or leak down tests?
Food for thought, certainly. They haven’t done a compression test yet (I’m paying for that, though, tomorrow after the repair is complete). I believe I should be ok based on the fact that it didn’t lose all the coolant, there’s no smoke, no unusual sound (misfiring, etc.). It’s been driven twice since: once on to the tow truck and once into the garage. I actually believe the 283 was a false reading of some kind. I don’t think it got that high. I think at some point (but my eyes weren’t on the scan gauge, the temp skyrocketed). I think if it was genuinely at 283 there would have been a more catastrophic outcome… do you happen to know where in-line the temp is captured? I’m certainly looking forward to the results of the test and the repair tomorrow.
 
Had heater T crumble in my hand, with no compatible T available a quick fix was soldering copper fittings that was probably 10 years ago and no more crumbling plastic.

Short high heat cycle of motor probably OK, changing oil and sampling could give insight as to how motor was affected.

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Had heater T crumble in my hand, with no compatible T available a quick fix was soldering copper fittings that was probably 10 years ago and more crumbling plastic.

Short high heat cycle of motor probably OK, changing oil and sampling could give insight as to how motor was affected.

View attachment 2735597
Good pic. I’d suppose the heater tees are the pesky heater hose of the 80s… but much easier to get access to.
 
While going through a stretch of up-and-down switch-back turns in Custer State Park in South Dakota, I heard a noise from the motor and glanced down to my scan gauge FWT reading— 283!

Was the coolant temp on the gauge cluster high?
 
Was the coolant temp on the gauge cluster high?
Great question… I never bothered to look, as odd as it sounds. Was so distracted with navigating the turns and then handling the crisis I didn’t bother to check (I focused on the scan gauge, saw the code it was throwing, and the temp). It may have been because I’ve been conditioned to know that the dash gauge is mostly a dummy gauge and reads wildly… or so I’ve read on mud many times.
 
yes, unfortunately, it's one of those potential issues that you can easily "see" from the outside. I think it really is a good idea to change to metal Tees before venturing too far out. So easy to do in your driveway. Worth taking the few minutes.
 
Food for thought, certainly. They haven’t done a compression test yet (I’m paying for that, though, tomorrow after the repair is complete). I believe I should be ok based on the fact that it didn’t lose all the coolant, there’s no smoke, no unusual sound (misfiring, etc.). It’s been driven twice since: once on to the tow truck and once into the garage. I actually believe the 283 was a false reading of some kind. I don’t think it got that high. I think at some point (but my eyes weren’t on the scan gauge, the temp skyrocketed). I think if it was genuinely at 283 there would have been a more catastrophic outcome… do you happen to know where in-line the temp is captured? I’m certainly looking forward to the results of the test and the repair tomorrow.

Temp sensor was reading an air pocket (steam) not coolant temp. I think you're fine.
 

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