2LTE Overheating Issue + Future Roadtrip = Questions (4 Viewers)

[TheBussman]

I imported a 1993 LJ78 from Japan and would also appreciate a thermostat part number verification if you'd be so kind. I have a few Japanese websites saved that I'm looking part numbers up on and the one I've found for my LC is PN: 90916-03062 (88-100, is that the 88 previously mentioned?) found on the MegaZip website. I didn't see any rules about posting PNs or websites so I'll always share all info I have, all the time. View attachment 3996396View attachment 3996397

I am experiencing what I would say is over pressure relief draining from the reservoir cap after driving easy in 110°F+ temps for 30 mins or so. Thermostat gage rises above the usual half way point after driving at 120 kph going uphill or driving long distances the AC stops blowing hot. At which point from driving my dad's '79 F350 Custom, I turn the heat on full blast which drops the thermostat low enough to drive normally, quite unpleasant at 110°F+ temps. I have topped off fluids a couple times in the past few months but not super often & not a lot of fluid.

Shame on me for knowingly driving with a couple of the tubes leaking at the joints (15000 km, multiple 1k elevation gains & in Nevada summer temps). One of the hoses was sealed with something as you can see in one of the pics I uploaded. After watching multiple videos, I now realize how bad leaks & air in the coolant system are and I'm looking at getting this fixed ASAP. That said, I haven't blown up the engine yet (knock on wood) driving as far as I have & as hard as I have in the past year. I like fixing machines and there's a lot to learn on this old of a vehicle. I was an aviation electrician in the Navy for 13 years and I like working on cars. I'm a self proclaimed, "learn as I go YouTube mechanic". Owning my first old diesel is a whole new ball game and I've been reading threads on this forum for a while now. I appreciate all you folks sharing such great info! Thanks for the help!

test for a cracked head first.

 

[Dprio34]

@MckMac11 , I agree with @TheBussman , sounds like it may be a cracked head (hopefully not) but it sure sounds like the symptoms you described. I’m out of town right now, but PM me, and you can swing by my place and we can take a look at it.

 

[MckMac11]

I appreciate you two responding so quickly! @Dprio34 I sent you a PM.

 

[MckMac11]

More data, I went to a mechanic who comes highly recommended here in Vegas from a buddy of mine. Turns out one of this guy's mechanics used to work on LCs back in his home country. He quickly identified that there is fluid leaking from the head to engine block surface where the gasket would be. I attached a pic for reference. I'm reporting because the mechanic mentioned needing to retorque the engine block bolts after a long period of time. Have you guys heard of this needing to be done for this issue?

 

[OGBeno]

No.

 

[Eurasiaoverland]

There is no procedure for retorquing the head bolts on an L engine. You need to replace your head gasket, and almost certainly your cylinder head as well.