Not up to speed on diesel so just guessing.

Who did the work, you or a shop?

Since the head was off the injector system could have been screwed up somehow. Does this engine have glow plugs for starting, if so are they working.

Is there something on the intake air system that monitors air flow to adjust the fuel flow or is this just mechanical system running strictly off of engine RPM to turn a pump.

White smoke could be unburned fuel. The black some is excess fuel in the combustion system.

The engine appears to be getting too much fuel.

 

It's in the garage again



A garage here in Bangkok did the work.

check the diesel pump timing...


Diesels don't have throttle bodies, you change engine speed by the amount of diesel injected, so basically the gas pedal adjusts the quantity.(the 2L-TE does have some kind of throttle flap tho, but its purpose is still a mystery for me).

I will have the timing checked. Wrong timing could be a part of the picture.

you either have further damage to the head or the head gasket was improperly installed.it sounds like you have lost compression in one or more cylinders.diesels are pressure or heat ignition engines.the newer diesels because they have lower compression than the bigger diesels use glow plugs to assist in starting.the smoke sounds like it is from improper combustion or low compression.you could possible have an injection pump out of time that would do something similar to what you are describing.i have not worked on any of the Toyota 4 cylinder diesels but have rebuilt many like engines.you need three main things to make a diesel start,cranking rpm( speed from the starter),compression,and fuel at the proper time.
i would start by checking the pump timing and if that is OK a compression test.i don't know why you replaced the head gasket but it might also be something else a cracked head or valves that was missed.i know this might sound like a very dumb question but did by chance anyone put gasoline in instead of diesel that will cause a diesel to smoke like wildfire and not run or run very badly.hope some of this might help you.good luck

Yes, there was lost compression for sure.

Guys, thanks for the replies. After going through this carefully, I took the truck to a garage owner up country since it's difficult to trust auto mechanics in Bangkok unless you know them personally, and even then it is a risk since there is no end to the scamming going on.

I will give you an example. A guy comes in with his truck for cylinder head repair. The mechanic calls him up anyhow and tells him that the head is cracked. The owner goes to the garage and is shown a similar cylinder head with a crack, and he pays for a new head. Then the garage puts his old cylinder head on again and has a nice profit. (There is also another practice going on here, namely selling used oil filters as new after cleaning and re-spraying old ones, and putting a plastic seal on them.) The only chance to get real parts is to buy them yourself from the dealer's garage.

Anyhow, after reading the posts here I took the truck to a garage I trust some 270 km from Bangkok. There the engine was dismantled today and they found out the following:

A wrong type of cylinder head gasket had been installed. The gasket that is needed is a layered metal gasket, and not the thin type. The reason is that the cylinder head needs to be re-planed, it has already been planed once but the second planing means so much metal has come off that one needs to compensate with a thicker gasket.

Oil was oozing out of the gasket that was put in last week, and the cylinder head was not tight so loss of compression made starting difficult.

The cylinder sleeves were found to be very worn and will all be replaced, and pistons and piston rings as needed.

And the cylinder head will be re-planed as it was a little warped by overheating, it is not cracked which saves me quite some money.

Once again, thanks for your answers, guys. I am not driving any special or customized kind of truck with a big gasoline engine (although I may get one in the future) but I plan to change the rim from 15 to 16 inches as that will give me better mileage on my old truck.

Good luck to you all.

 

check the diesel pump timing...

Is there something on the intake air system that monitors air flow to adjust the fuel flow or is this just mechanical system running strictly off of engine RPM to turn a pump.

Diesels dont have throttle bodies, you change engine speed by the amount of diesel injected, so basically the gas pedal adjusts the quantity.(the 2L-TE does have some kind of throttle flap tho, but its purpose is still a mystery for me).

 

hard to statrt

you either have further damage to the head or the head gasket was improperly installed.it sounds like you have lost compression in one or more cylinders.diesels are pressure or heat ignition engines.the newer diesels because they have lower compression than the bigger diesels use glow plugs to assist in starting.the smoke sounds like it is from improper combustion or low compression.you could possible have an injection pump out of time that would do something similar to what you are describing.i have not worked on any of the Toyota 4 cylinder diesels but have rebuilt many like engines.you need three main things to make a diesel start,cranking rpm( speed from the starter),compression,and fuel at the proper time.
i would start by checking the pump timing and if that is OK a compression test.i don't know why you replaced the head gasket but it might also be something else a cracked head or valves that was missed.i know this might sound like a very dumb question but did by chance anyone put gasoline in instead of diesel that will cause a diesel to smoke like wildfire and not run or run very badly.hope some of this might help you.good luck

 

Guys, please help and give me some pointers if you can.

I had the cylinder head gasket changed on my Hilux 1993 2.5 diesel last week. Since then, it is difficult to start the truck when the engine is cold. There is a lot of white smoke coming out of the exhaust when I crank the engine but the engine does not fire at all. The only way to start the engine is to have the truck towed by another car or pushed downhill. I know the battery is OK although not new, could it be the battery? Somehow I don't believe that.

Another thing is, there is a lot of black smoke coming out the exhaust while accelerating or climbing uphill, I think something may be wrong with the injector pump, although that is also difficult to understand since I have driven the truck only 60.000 km since the injector pump and injectors were replaced with new parts. Engine was rebuilt 45.000 km ago, new piston rings, pistons, bearings etc.

id say you have a broken piston ring. white smoke when you are cranking it over means ther is raw fuel going through your motor. black smoke means you are getting an incomplete burn both related to low compression. when you get your truck pull started the motor can turn faster than when you use the starter, so more heat is generated and you can start your motor.

if you just want to get it started i suggest either. wait till your glow plugs shut off, and give it a little spray in the intake. its how we have to start our diesels in the winter time and when used properly wont harm the engine

 

Thanks for the reply moldycheese, and other posters. I haver seriously considered your advice and it is valuable. This is a very useful Toyota board.