Got my Blackstone analysis...now what? Replace head gasket? Wait? *sigh* (1 Viewer)

Joined
Mar 12, 2021
Messages
51
Location
Big D, Texas
Welp, got the Blackstone analysis back. (see below...'94 FZJ80, ~85k miles, RHD Aussie import). Analysis points to a coolant leak. I noticed what appeared to be the dreaded "milkshake" in my coolant reservoir, so did an analysis to be safe. (The reference to WD-40 is because I had recently lubed the pump I used to extract the oil for the sample, and I noted that when I sent the sample in.)

94 LAND CRUISER-210502_redacted_001.jpg


Is a failing head gasket really the ONLY thing that would cause coolant in oil/oil in coolant? 85k seems way early for a failing gasket...but then again it's a 27 yo vehicle, so maybe it's just age.

I am not losing a noticeable amount of coolant or oil yet, BTW. Levels have been steady for about three weeks driving the truck about every other day. No other performance issues whatsoever (other than a starter I'll be replacing tomorrow).

Do I preemptively have the gasket replaced before things get "bad?" Do I do nothing now, change the oil, drive it for a while and send another analysis to see if the results are the same or worse?

Could there be coolant showing up in the oil (and vice-versa) left over from before a previous repair? I ask this because the engine is very clean, gasket looks in good shape (as much as you can see with the engine intact, and most hoses appear new, suggesting the possibility that the job was done before. Of course maybe an unscrupulous PO cleaned it up and replaced hoses for that very reason: to make it appear all was well. Unfortunately with it being an import, I don't have great records from any PO. Just the equivalent of a carfax showing no wrecks, clean title, never stolen, etc. Maintenance history is anyone's guess.

IMG_20210514_094847264_HDR.jpg


IMG_20210514_094902473_HDR.jpg


IMG_20210514_094910701_HDR.jpg


IMG_20210514_094928874_HDR.jpg


Would it be worthwhile completely draining/replacing the coolant as well as the oil prior to another analysis? Would that limit the possibility of any "false positives?"

Sorry if some or all of these questions are dumb and/or answered elsewhere...I'm no mechanic, but I'm learning a lot from this forum and I'm loving having a vehicle I actually enjoy wrenching on! Thanks in advance for your thoughts.
 

Heckraiser

SILVER Star
Joined
Aug 5, 2010
Messages
5,102
Location
Colorado
I would thoroughly flush the coolant out and replace, change the oil and send them another sample in 3k miles. In the meantime, watch for more warning signs and stop driving if any pop up. That's just me.

:edit: what does the radiator look like under the cap?
 

cme4lyt

SILVER Star
Joined
Jan 2, 2010
Messages
1,401
Location
Walnut Creek, CA Bay Area
If it was me, and yes I’m a little OCD, my thought is that you could do all the other things you mention and still really never know if you had/have a HG problem ? I would have to tackle it for simple ‘piece of mind‘ and so I don’t ever have to revisit it again.

Again, a little extreme but that’s my thinking...
 
Joined
Nov 9, 2012
Messages
11,070
Location
Olathe, KS, USA
IDK what your "Driving the truck every other day" amounts to, but if it's not at least 30 minutes of driving and getting EVERYTHING up to temperature to "burn off" any moisture, then yes, it's possible condensation has settled into the oil and has contaminated your test results.

With that much unknown, I would go one of two routes:
1) Remove the head and do all pre-emptive maintenance, including HG.
2) Flush everything, do all fluids, drive it for a while and retest.

Personally, I would do #2.

The coolant in that reservoir looked like the green/red mixed coolant that was in my truck when I got it. I SHOULD have dumped it, flushed it, rinsed it, and replaced it, but I didn't and it cost me a radiator.

Replace the radiator cap (with OEM)

May as well tdo the thermostat and gasket and any necessary cooling system hoses (PHH, 2nd PHH, heater control valve, heater hoses at rear of head, rear heater hoses, etc) as well.

Change your oil and filter
Drain your coolant, including the block drain, flush with a garden hose, then fill with distilled water and drive for 30 minutes, then drain and fill with distilled again. DO this 4 times, then fill with your choice of red or green coolant (not both).

Drive the truck every day for 30 days, drain the oil and retest. Make sure you get the truck up to temp and I don't mean seeing the engine temp needle in the middle of its range. I mean get the whole truck out on the highway, let it get fully up to temp. This will flash off any moisture in the engine, axles, transmission as well.

Driving them is GOOD for them.

Advise your test results after all this.
 
Joined
Mar 12, 2021
Messages
51
Location
Big D, Texas
I would thoroughly flush the coolant out and replace, change the oil and send them another sample in 3k miles. In the meantime, watch for more warning signs and stop driving if any pop up. That's just me.

:edit: what does the radiator look like under the cap?
Messy. Def will be doing a complete flush and replace the fluid.
IMG_20210514_121851323.jpg
 
Joined
Mar 12, 2021
Messages
51
Location
Big D, Texas
IDK what your "Driving the truck every other day" amounts to, but if it's not at least 30 minutes of driving and getting EVERYTHING up to temperature to "burn off" any moisture, then yes, it's possible condensation has settled into the oil and has contaminated your test results.

With that much unknown, I would go one of two routes:
1) Remove the head and do all pre-emptive maintenance, including HG.
2) Flush everything, do all fluids, drive it for a while and retest.

Personally, I would do #2.

The coolant in that reservoir looked like the green/red mixed coolant that was in my truck when I got it. I SHOULD have dumped it, flushed it, rinsed it, and replaced it, but I didn't and it cost me a radiator.

Replace the radiator cap (with OEM)

May as well tdo the thermostat and gasket and any necessary cooling system hoses (PHH, 2nd PHH, heater control valve, heater hoses at rear of head, rear heater hoses, etc) as well.

Change your oil and filter
Drain your coolant, including the block drain, flush with a garden hose, then fill with distilled water and drive for 30 minutes, then drain and fill with distilled again. DO this 4 times, then fill with your choice of red or green coolant (not both).

Drive the truck every day for 30 days, drain the oil and retest. Make sure you get the truck up to temp and I don't mean seeing the engine temp needle in the middle of its range. I mean get the whole truck out on the highway, let it get fully up to temp. This will flash off any moisture in the engine, axles, transmission as well.

Driving them is GOOD for them.

Advise your test results after all this.
Thanks for the detail. I'm leaning toward this plan as opposed to just diving right in to the HG replacement/head rebuild. That's assuming the block test kit as recommended by @EricG doesn't come back with definitive proof that I need a new HG. 🤞 As for "driving every other day," the truck is my DD, but now that I work from home and the kiddo is driving herself to/from school, there are days when I don't drive at all. But I love driving her, so a daily highway drive in the name of troubleshooting and maintenance is just fine by me. :D
 

leonard_nemoy

SILVER Star
Joined
Jan 19, 2005
Messages
2,318
Location
South west utah
How long have you had the rig and how many times have you changed the oil?


Blackstone knows there sh*t. Just do what they say. Change the oil and send another sample back. Whether your taking about chemical analysis of blood or oil the same rules applies. Multiple samples and analysis over time will give much more data than a 1 time analysis. Those results could easily be a one off, multiple test results will give you a much more accurate picture.

Even if the head gasket is going bad you might be able to drive it for another year before it fails catastrophically. Why spend $$$$ fixing it now. For all you know the rig might get stolen or totaled within the month.
 
Last edited:

Users who are viewing this thread

Top Bottom