new head causing knocking (HELP)

[adamhardwidge]

Recently fitted new head, water pump head gasket and bolts, now im getting a loud knocking (sounds like detonation), checked injectors and timing, tappetts, vacuum pipes etc, still no change, please does anyone have any ideas to help me

[Northern Bongolow]

warped manifold ??

love the forum name .

[David Edwards]

Is it "diesel Knock" does it go when you get to a certain speed, is the timing definitely correct, the mixture right, all worth checking. So I have been told re mine,lol.

[adamhardwidge]

have not thought of warped manifold but it was fine until new head fitted due to cracked head, the timing marks all line up perfect, it does'nt do it on tick over only when accelerating and revving though the range, if you move the fuel pump it did stop but come straight back again, im running out of ideas

[Simon Jones]

Put your location in your profile as someone local may be able to assist or suggest a Bongo specialist in your area.

[mikeonb4c]

Get Bongo or diesel specialist to look at it?

[Northern Bongolow]

did you/they check the manifold before refitting, they are really prone to warping, especially no1 stud nearest the alternator.

[adamhardwidge]

to be fare i didn't check the manifold but using a stethoscope, it sounds more to the rear of the engine, near the bottom the head, and discovered, if you move the fuel pump, it will stop for 2 mins then comes straight back weird.

[Northern Bongolow]

as the cam is timed off the fuel pump ???. rip the rocker off if you havnt done already. did you set the gaps yourself, as some have come to grieff with presuming a built up head was ready to go and not set the valve gaps correctly, or the nuts come loose etc.

[teenmal]

Hi Adam,

If you slacken each injector pipe in turn,and the noise disappears this will tell you what cylinder to look at.

Cheers.

[adamhardwidge]

Hi thanks for all your replys, i have set all rockers and slacked them off but still there, also undone injectors revs drop but noise still there when revving, getting worried now p.s the manifold is not warped lol

[briwy]

This may sound daft but are you sure that when the head was fitted nothing dropped into one of the cylinders.
It happened to me years ago on a Mini engine. Horrendous noise, took the plugs out and found a small washer on one of the cylinders, not much damage fortunatley, just a few scratches on top of the piston.

[helen&tony]

Hi
New Head???
COULD, I say COULD be the cambelt slipped a notch if it was not set properly???
Cheers
Helen

[adamhardwidge]

Cam belt all set properly and double checked, changed the very old fuel filter does anyone knkw how to bleed the system properly.....

[mikeonb4c]

Cam belt all set properly and double checked, changed the very old fuel filter does anyone knkw how to bleed the system properly.....

Although the manual may say otherwise, I've yet to hear of a Bongo pump that doesn't self-prime, if thats what you are asking (apologies if not). Mine never has needed bleeding/priming.