80 series blowing smoke loosing coolant

D

danielway284

Joined
Aug 19, 2021
Messages
7
Location
auckland new zealand
Been scrolling the forums trying to find some info but posting now as to still unsure!

My 1990 1HD-T has been losing a small amount of coolant and blows a bit of black smoke (which I think is normal) and then blue smoke upon start up (see attached) no crazy amounts of smoke but would like to get to the bottom of it over the nz lockdown

not sure if these problems are linked but any info would be much appreciated

Truck has done 350 xxx k’s

B61590C6 FBDD 4ECF 91F4 361A0A30F604
 
D

danielway284

Joined
Aug 19, 2021
Messages
7
Location
auckland new zealand
Also forgot to add, oil is not milky and no sign of bubbles coming through the radiator cap
 
leonard_nemoy

leonard_nemoy

SILVER Star
Joined
Jan 19, 2005
Messages
2,690
Location
South west utah
I am certainly no expert on that motor but the blue smoke probably isn't a very big deal for a 31 year old diesel motor.

As far as the coolant loss goes I would recommend doing a pressure test on the cooling system and giving all the hoses and components a good inspection. You probably have a small leak somewhere that doesn't make it to the asphalt and the pressure test will make it easier to spot.

Amazon product

If your really worried about a head gasket than run a combustion gas leak test with a kit like this.

Amazon product

Goodluck
 
mudgudgeon

mudgudgeon

SILVER Star
Joined
Dec 17, 2007
Messages
5,417
Location
Across the pond, and upside down
Agreed. Pressure test the cooling system.

1hd-t will typically blow a short puff of blackish smoke on hard troth as it comes off idle and builds revs. This is 100% normal.

Blue smoke on start up could be anything from worm rings (compression test), worn valve stem seals, to wear in the injection pump, or dirty/poor condition injectors
 
mudgudgeon

mudgudgeon

SILVER Star
Joined
Dec 17, 2007
Messages
5,417
Location
Across the pond, and upside down
Ps, 350k km, it's just been run in if it's been looked after.

But injectors and pump might be ready for some attention.

Pps, you'll generally get more answers from the diesel crew if you post in the Diesel Tech and 24 volt section, not 80 series tech.
 
80HDTX

80HDTX

Joined
Mar 4, 2021
Messages
61
Location
Jindabyne, NSW, Australia
Likely a head issue, check radiator connections and coolant lines for leaks, if none then pressure test.

Chewing coolant isn’t a good sign, usually it’s finding its way out through the block through the head. When was your head gasket last changed? Blue smoke on idle after warm could indicate antifreeze vapour in the mix.

Keep topping it up and watch your temps. Note down how much you top it up by; and how frequently, observe for change. Fingers crossed it’s just a radiator issue!
 
mudgudgeon

mudgudgeon

SILVER Star
Joined
Dec 17, 2007
Messages
5,417
Location
Across the pond, and upside down
Losing coolant cos also just be due to an old radiator cap that is no longer holding pressure.
Or, the coolant return valve on the cap might not be functioning properly.

The cap is designed to allow coolant to escape as it heats and expands, then it also allows it to be sucked back into the radiator when it cools.

I had a cap that wouldn't allow coolant back in
 
F

Fairgame

Joined
Jul 10, 2021
Messages
54
Location
Zambia
Any coolant leaks will discolor a radiator, cap, or hoses. Your engine is fine. Have a good look at the back of the radiator.
 
D

danielway284

Joined
Aug 19, 2021
Messages
7
Location
auckland new zealand
Ps, 350k km, it's just been run in if it's been looked after.

But injectors and pump might be ready for some attention.

Pps, you'll generally get more answers from the diesel crew if you post in the Diesel Tech and 24 volt section, not 80 series tech.
Cheers mate,

Just replaced the radiator cap and did about 60kms today but wasn’t the solution and lost maybe 5mm off the radiator fluid so definitely a small leak but a leak none the less but fingers crossed it’s hoses/fittings.

in regards to the worn piston rings, taking my oil fill cap off to check blow by the cap hardly moves around with the engine running

Injectors and valves will be the next thing to inspect
 
D

danielway284

Joined
Aug 19, 2021
Messages
7
Location
auckland new zealand
Any coolant leaks will discolor a radiator, cap, or hoses. Your engine is fine. Have a good look at the back of the radiator.
Replaced the radiator cap, didn’t solve the problem but all cap was quite discoloured (red)

This wouldn’t indicate exhaust fumes?
 
D

danielway284

Joined
Aug 19, 2021
Messages
7
Location
auckland new zealand
Likely a head issue, check radiator connections and coolant lines for leaks, if none then pressure test.

Chewing coolant isn’t a good sign, usually it’s finding its way out through the block through the head. When was your head gasket last changed? Blue smoke on idle after warm could indicate antifreeze vapour in the mix.

Keep topping it up and watch your temps. Note down how much you top it up by; and how frequently, observe for change. Fingers crossed it’s just a radiator issue!
I only Have a service history of the last 50,000 ks and no history of a head gasket replaced, I drove 60kms today and lost about 5-10mm (0.2-0.4 of an inch) give or take, drove the vehicle from buying it roughly 1000ks and had to fill with around a litre (0.25 of a gallon). temp hasn’t exceeded anywhere over half since I have owned
 
Last edited:
mudgudgeon

mudgudgeon

SILVER Star
Joined
Dec 17, 2007
Messages
5,417
Location
Across the pond, and upside down
I only Have a service history of the last 50,000 ks and no history of a head gasket replaced, I drove 60kms today and lost about 5-10mm (0.2-0.4 of an inch) give or take, drove the vehicle from buying it roughly 1000ks and had to fill with around a litre (0.25 of a gallon). temp hasn’t exceeded anywhere over half since I have wonder

Is it still losing 1 litre/1000km? If so, I would say you have a leak somewhere. Does it drip when parked?
Is there any red staining on the engine block, or radiator, or chassis near the engine?

When my hdj81 radiator cap was no good, it showed up as a red stain on the radiator. Turned out it was coolant tracking down from the overflow tube and drying leaving coolant residue behind.

If your cap is stained red, it's probably just dirty Toyota Red coolant. If it's really old coolant, you may have some rust in the system too
 
80HDTX

80HDTX

Joined
Mar 4, 2021
Messages
61
Location
Jindabyne, NSW, Australia
I only Have a service history of the last 50,000 ks and no history of a head gasket replaced, I drove 60kms today and lost about 5-10mm (0.2-0.4 of an inch) give or take, drove the vehicle from buying it roughly 1000ks and had to fill with around a litre (0.25 of a gallon). temp hasn’t exceeded anywhere over half since I have owned
That’s fair consumption, are you getting your reading from the reservoir? Should be 0 ideally. Have you physically checked inside the radiator through the radiator cap opening? How’s the coolant looking? And as above the cap itself can cause some issues if it’s not sealing properly or on its way out.

Have you noticed any leaks or drips along the lines? It could just be that you have old cracked hoses and it’s evaporating before you’re noticing liquid, especially with that kind of usage. Seems like it’s going somewhere, just a matter of finding out where.
 
D

danielway284

Joined
Aug 19, 2021
Messages
7
Location
auckland new zealand
That’s fair consumption, are you getting your reading from the reservoir? Should be 0 ideally. Have you physically checked inside the radiator through the radiator cap opening? How’s the coolant looking? And as above the cap itself can cause some issues if it’s not sealing properly or on its way out.
Have you noticed any leaks or drips along the lines? It could just be that you have old cracked hoses and it’s evaporating before you’re noticing liquid, especially with that kind of usage. Seems like it’s going somewhere, just a matter of finding out where.
My reservoir was complete full once I noticed the lack in the radiator, as it spat out the overflow hose when I opened it while engine still had a small bit of heat to it. haven’t driven it enough to notice any increase as you can’t see the through the bottle. Inside the radiator does look quite rusty so maybe be worth flushing it out and replacing, but can’t find any leaks, along the lines yet, any specific/common spots to look at?

thanks heaps for the info
 
80HDTX

80HDTX

Joined
Mar 4, 2021
Messages
61
Location
Jindabyne, NSW, Australia
No worries. Check top and bottom hoses, all clamps, connections to block and from radiator. The coolant lines connect up to the heater core also, check the valve passenger side on the fire wall and make sure there’s no leaks there.

Another spot to check is for dampness in your passenger footwell, sometimes the heater core can fail and leak coolant underneath the carpet often going unnoticed until it’s bad.

Being a 1hdt, your turbo is coolant and oil fed, check connections there. As there is plenty of heat down there the hoses can often crack and deteriorate if not checked or maintained.

Lots of things that it could be, but the list is finite. Sounds like you need a flush regardless. Old rusty radiator means debris (rust / contaminants) could be getting blocked intermittently and you’re losing coolant due to back pressure forcing coolant out of the overflow hose.

Run a pressure test or take it into a shop if you’re not sure just for safe measure.
 
D

danielway284

Joined
Aug 19, 2021
Messages
7
Location
auckland new zealand
Update!

Been using a diesel additive which fixed a lot of the smoke, very minimal now.

Just had my mechanic around and it’s not looking too good, bubbles through the radiator when the truck is brought up to normal operating temperature, all though the exhaust gas test showed no sign of exhaust gases, the bubbles were also very small.

Is it possible for the cooling system to pressurise for any other reason then the a bad gasket?

Cheers
 

Similar threads

mellowdave
Replies
11
Views
407
zapatius
zapatius
Stiles
Replies
7
Views
291
AirheadNut
A
Replies
10
Views
378
BILT4ME
BILT4ME
B
Replies
4
Views
242
clx16
C

Users who are viewing this thread

Top Bottom