The reality of the Landcruiser Head Gasket Issue

[Plains Cruiser]

Thanks @flintknapper and others - the straw going into the reservoir was indeed clogged. Gonna order a new one (and cap for good measure) and see where things are at.

 

[thelal]

That seems to point to a defective thermostat, not fully opening when engine heats up.



You won't see movement until the thermostat opens

Both stats (old and new) passing boiling in saucepan test. Can I run without any t-stat temporarily for a few mins? As can then see if any movement in water (on top of rad) to verify that water pump is working (and also Tstat issue)

 

[flintknapper]

Both stats (old and new) passing boiling in saucepan test. Can I run without any t-stat temporarily for a few mins? As can then see if any movement in water (on top of rad) to verify that water pump is working (and also Tstat issue)

Yes. Since you wouldn't see any movement (or very little) until the Tstat has fully opened.

Water Pumps tend to be quite reliable on these vehicles (if OEM) but it wouldn't hurt to do what you propose.

I also run a 170°F thermostat in my L/C because I live in a hot climate and it gives the engine cooling system a little head-start. I also modified my fan clutch using 15K silicone fluid. Those two items can help with vehicles that occasionally run on the 'edge' of getting hot (above 210°F).

But I must say.....I am a little perplexed given what we know about yours.

 

[thelal]

Yes. Since you wouldn't see any movement (or very little) until the Tstat has fully opened.

Water Pumps tend to be quite reliable on these vehicles (if OEM) but it wouldn't hurt to do what you propose.

I also run a 170°F thermostat in my L/C because I live in a hot climate and it gives the engine cooling system a little head-start. I also modified my fan clutch using 15K silicone fluid. Those two items can help with vehicles that occasionally run on the 'edge' of getting hot (above 210°F).

But I must say.....I am a little perplexed given what we know about yours.

Took old tstat out and refilled. Temp engine 55f before turned on with intake temp 55f as evening time and much cooler than yesterdays heat during the day.

Ran truck for 30 mins+ with Rad cap open and couldn't get temps up above 140f.

Turned on heaters in cabin with ac so load a little with engine temp 136f, top ubend hose above engine 127f, top hose into rad 110f and bottom hose 92f. Some low heat from cabin vents.

With ac off an heaters 133f on engine, 107f to Rad hose and 92f bottom
Seeing small movement of water in Rad R to L but not strong. Earlier too many suds to see right in and had to finger them out.

Rev'ed engine to 2k twice and seeing much more stronger flow on Rad. Top Rad hose 111f, 124f ubend hose and 95f on lower.

So "appears" water pump working but don't if its enough (fully funtioning or rad maybe stopping some of the flow). Will post video so someone can compare. Certainly at start no movement at top (suds layer) and maybe tiny circular flow.

No bubbles in Rad at all and forgot to check in radiator overflow.

So weird that completely different than yesterday. Was tstat sticking then?
Does having a tstat vs no tstat have such a difference

 

[thelal]

Took old tstat out and refilled. Temp engine 55f before turned on with intake temp 55f as evening time and much cooler than yesterdays heat during the day.

Ran truck for 30 mins+ with Rad cap open and couldn't get temps up above 140f.

Turned on heaters in cabin with ac so load a little with engine temp 136f, top ubend hose above engine 127f, top hose into rad 110f and bottom hose 92f. Some low heat from cabin vents.

With ac off an heaters 133f on engine, 107f to Rad hose and 92f bottom
Seeing small movement of water in Rad R to L but not strong. Earlier too many suds to see right in and had to finger them out.

Rev'ed engine to 2k twice and seeing much more stronger flow on Rad. Top Rad hose 111f, 124f ubend hose and 95f on lower.

So "appears" water pump working but don't if its enough (fully funtioning or rad maybe stopping some of the flow). Will post video so someone can compare. Certainly at start no movement at top (suds layer) and maybe tiny circular flow.

No bubbles in Rad at all and forgot to check in radiator overflow.

So weird that completely different than yesterday. Was tstat sticking then?
Does having a tstat vs no tstat have such a difference

In morning took off belts and squeaking on water pump. Not all the time but each time I spin it , it starts with a squeak and goes away. Same which every way I spin it ; L->R, R->L . Presume it should be silent

Have new water pump and radiator on the way from RockAuto ; seemed to be the best price and shipping (from USA->Bosnia) - should arrive on the 4th . I'll get my fireworks ready

 

[thelal]

Got new water pump (Aisin) delivered and replaced. New one is stiff and doesn't 'spin' freely. Quite and no noise.
Old one spins a little and squeaks. Cleaned surface good before put on with new gasket.

Radiator out (took out both battery trays) and actually seems ok (bit dark at the moment but with flashlight can see thru on both sides w/o any apparent breaks/blockages etc.). Bit dirty on o/s and especially lower down but methinks it "looks ok". Will check more in the morning but suspect a good cleaning (power wash) and would look pretty good. Inside (as far as I can see) all clear no residue or coating.
Getting lower ATF hose need outlet at bottom was a PITA to get off (good 20 mins wiggling it with pick 90 degrees trying to loosen etc. ). Rest went ok per several of the other helper posts.
Radiator (TY 1918) got held up in customs so expect tomorrow ; at least all ready 2 put in

 

[ToothDr]

The reality of the 80 series Land Cruiser head gasket is this. After 25-30 years on an original 1FZFE head gasket there are only two types of owners. Those that have replaced the head gasket and those that will replace the head gasket in the near future. The only question is do you replace on your schedule or replace when it decides to go.