Head Job
So, for a while now, there has been a Knocking coming from the engine. I have asked several folks, in the know and have had several different answers. Some were saying it is the Vacuum Pump, Some were saying it is the Valves, Some were saying it is the Lifters. I was thinking along the lines that it might just be "Diesel Knock". A few had said that it could be Diesel Knock.
After checking the Valve Rocker Clearances (Tappets) were correct the next check I did was to pull the Injectors out. They all were very Gummed up with thick Black Carbon and also looked Oily. It was like the burning in the combustion chamber wasn't happening properly and had left unburnt fuel. It was seeing the injectors is such a state that I decided to take the head off. The Tappets did need adjusting, but I wasn't convinced that this was the problem. The Knock sounds more like it is one cylinder than all of them.
Have a listen to the video.
Here are the Injectors.
It's a wonder they actually sprayed any fuel evenly.
So after taking the Head off, things didn't look as bad as what I was expecting. The head surface wasn't bad, but the backs of the valves and the ports were quite bad, especially the exhaust valves. I put the head to one side and set to on cleaning up the Pistons.
Cleaning Carbon off is not as easy as you think. I finished up using Mr Muscle Oven Cleaner and WD40 along with an old Wood Chisel as a scraper. I also had some Scotch Brite as a scrubber, an old Tooth Brush and a Wire Wheel in a drill. The old Gasket was just as problematic to removed as it had welded its self to the head deck.
I used the old chisel and wire wheel on the deck to get the gasket off, but I needed a softer approach on the pistons. This is where the Oven Cleaner and WD40 come in. Spray it on and leave for a while and then scrap and brush and rub it off. Eventually, the Pistons and the Deck were clean.
Next thing to do was the Head. I removed the Valves to find the backs of the Inlets Gummed Up with Black Oily Carbon Goo. The inlet ports were good or should I say good'ish. There wasn't much crud about and this gave me a hint that the turbo was okay and not leaking oil. The Goo is the problem of having leaking Stem Seals.
The Exhaust Valves had plenty of Burnt on Carbon but cleaned up well on the Lathe. I used an Air Driven Die Grinder on the backs of the valves while they were spinning in the lathe.
I didn't take a photo of the backs of the Exhaust Valves, but to get the picture, they looked like the Inlets but burnt on harder.
I used the Die Grider to clean up the ports on the head. As said earlier, the inlets weren't bad and a few squirts of WD40 and a screwdriver to scrape away the crud, the ports came up clean. However, the Exhaust Ports were caked in crud.
It's a bit difficult to see in the photos but I'm sure you get the idea?
If you click on the photo, you'll get an enlarged photo come up before you.
I cracked on and clean everything.
The carbon in the exhaust ports was absolutely caked on.
I lapped all the valves in and fitted new Stem Seals.
Here are a few videos to watch.
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Here is the finished job done.
Head back on and everything torqued up.
I also removed the Vacuum Pump and blanked of the hole it sits in.
It started first turn of the key and ran as it should.
The Knock has gone and it sounds just right.
________________________________________
------------------------------------------------------------
We went away on Holiday down to Sixpenny Handley.
It never missed a beat all the way there and back.
No Smoke now either.
I'm much happier now it is back up and running like it should.
------------------------------------------------------------
MPG is up as well. The best I got when I first inserted the engine 3 years ago was 27mpg when towing the caravan. This last week or so with towing the caravan, the mpg is up to just shy of 30. The running around while on holiday without the caravan saw 35mpg. I'm yet to do a good long run without the caravan to see what the mpg goes up to. I'm guessing it'll be high 30's?
_________________________________________
After checking the Valve Rocker Clearances (Tappets) were correct the next check I did was to pull the Injectors out. They all were very Gummed up with thick Black Carbon and also looked Oily. It was like the burning in the combustion chamber wasn't happening properly and had left unburnt fuel. It was seeing the injectors is such a state that I decided to take the head off. The Tappets did need adjusting, but I wasn't convinced that this was the problem. The Knock sounds more like it is one cylinder than all of them.
Have a listen to the video.
Here are the Injectors.
It's a wonder they actually sprayed any fuel evenly.
So after taking the Head off, things didn't look as bad as what I was expecting. The head surface wasn't bad, but the backs of the valves and the ports were quite bad, especially the exhaust valves. I put the head to one side and set to on cleaning up the Pistons.
Cleaning Carbon off is not as easy as you think. I finished up using Mr Muscle Oven Cleaner and WD40 along with an old Wood Chisel as a scraper. I also had some Scotch Brite as a scrubber, an old Tooth Brush and a Wire Wheel in a drill. The old Gasket was just as problematic to removed as it had welded its self to the head deck.
I used the old chisel and wire wheel on the deck to get the gasket off, but I needed a softer approach on the pistons. This is where the Oven Cleaner and WD40 come in. Spray it on and leave for a while and then scrap and brush and rub it off. Eventually, the Pistons and the Deck were clean.
Next thing to do was the Head. I removed the Valves to find the backs of the Inlets Gummed Up with Black Oily Carbon Goo. The inlet ports were good or should I say good'ish. There wasn't much crud about and this gave me a hint that the turbo was okay and not leaking oil. The Goo is the problem of having leaking Stem Seals.
The Exhaust Valves had plenty of Burnt on Carbon but cleaned up well on the Lathe. I used an Air Driven Die Grinder on the backs of the valves while they were spinning in the lathe.
I didn't take a photo of the backs of the Exhaust Valves, but to get the picture, they looked like the Inlets but burnt on harder.
I used the Die Grider to clean up the ports on the head. As said earlier, the inlets weren't bad and a few squirts of WD40 and a screwdriver to scrape away the crud, the ports came up clean. However, the Exhaust Ports were caked in crud.
It's a bit difficult to see in the photos but I'm sure you get the idea?
If you click on the photo, you'll get an enlarged photo come up before you.
Just started to clean this one.
I cracked on and clean everything.
The carbon in the exhaust ports was absolutely caked on.
I lapped all the valves in and fitted new Stem Seals.
Here are a few videos to watch.
------------------------------------------------------------------------------
Here is the finished job done.
Head back on and everything torqued up.
I also removed the Vacuum Pump and blanked of the hole it sits in.
It started first turn of the key and ran as it should.
The Knock has gone and it sounds just right.
________________________________________
------------------------------------------------------------
We went away on Holiday down to Sixpenny Handley.
It never missed a beat all the way there and back.
No Smoke now either.
I'm much happier now it is back up and running like it should.
------------------------------------------------------------
MPG is up as well. The best I got when I first inserted the engine 3 years ago was 27mpg when towing the caravan. This last week or so with towing the caravan, the mpg is up to just shy of 30. The running around while on holiday without the caravan saw 35mpg. I'm yet to do a good long run without the caravan to see what the mpg goes up to. I'm guessing it'll be high 30's?
_________________________________________
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