Won't start after top end overhaul

Hi, I'm hoping someone out there can point me in the right Direction. I've just replaced the head gasket and valve seals on my 300tdi discovery 1 as well as giving everything a good clean and once over.
Having put everything back together again it turns over but won't fire up. I'm new to the discovery but quite handy with mechanics in general.
I have blead the fuel system at the filter /return pipe and have good squirts at all 4 injector unions.
Glow plugs all working as they should.
Good battery
I have a 12v switchable supply to the fuel solenoid as the spider is faulty.
All valve clearance were adjusted according to the Haynes manual and the engine turns over fine with compression on all cylinders.

The motor ran fine with loads of power before overhaul but was noisy and head gasket was leaking a little oil hence the overhaul.

My compression tester is the push on style which isn't accurate enough so going to buy the proper gear tomorrow just to double check the compression is as it should but after that I'm stuck.

Would appreciate any advice
Kieran

If you haven't adjusted the timing and you have fuel at each of the injectors and you have compression then there really isn't too much more to check. Are you 100% sure that you have fuel at the injectors? There is a fuel stop solenoid on the injector pump which is the only thing I can think of that would cause this, but if you have fuel at the injectors then it can't be that.

But just to make sure, pull the wire off the stop solenoid when the ignition is on and see if you can hear a click.

Hi thanks for getting back, it's not the solenoid as definitely have fuel at the injector union and I have a faulty immobiliser spider so run 12v straight to the solenoid via a switch. I'm tempted to turn her over with injectors out but connected to double check they are firing correctly but there are obvious dangers!
Is it possible to put the rocker shaft back on after turning the crank over 180 degree out? The timing case was not touched and the fuel pump wasn't removed.

Think I've just answered my question, in a blonde moment I'm sure I put cylinder 1 to the top before fitting rockets but that's not always tdc! Hence timing will be 180 degree out. Can't wait to get home to check the theory. Will report back.

I don't think the timing will be 180 degrees out by that. You would have to have either moved the cam or the injector pump pulley in order to make that sort of mistake. And as you have only pulled off the head and put it back on then I think you are looking at something else being the issue.

Yeah blind alley I think , just gone back through the Haynes manual and nowhere does it mention having anything at Tdc so I followed instructions to the letter.
Oh well open to ideas again 😢

To be clear. If you loosen the injector pipes at the injector end and turn the engine over, do you have fuel coming out of all four pipes?

The only other thing I can think of is the injectors themselves. Are you definitely getting fuel through the injectors and a decent spray pattern?

I've only checked for fuel coming out of the fuel pipe where it connects to the injectors and all four have fuel. Is it safe to pull the injectors out of their holes and check the spray pattern?

Key said:

I've only checked for fuel coming out of the fuel pipe where it connects to the injectors and all four have fuel. Is it safe to pull the injectors out of their holes and check the spray pattern?

Click to expand...

Just undo the pipes on the injectors and see if any fuel comes out when you crank it. I suspect that you aren't getting any fuel to the injectors which is probably the fuel stop solenoid.

Sorry I Thought I'd made that clear. I have fuel supply to all four injectors. But I haven't checked the spray pattern coming out of the other end.

Rocker cover off, check the rockers/tappets for timing. They're towards the end of a rebuild, and if you're a bit weary, it's easy to go off count.

+1 on the above

Also, have you maybe damaged the injectors on assembly or perhaps there is a blockage somewhere on the injectors? Did you remove the injectors when you removed the head? Did you get the head skimmed? Did you lap the valves in?

You could remove the injectors as you said and see if there is a spray pattern. I think that is the next thing to do. Other than that, it may be head off time again...

Ok I'll try some of these ideas thanks guys.

Right, checked the valve clearance and all ok, didn't skim the head but replaced head gasket and gave all surfaces a good clean up using 400g wet and dry. All valves were lapped in and confident done properly.
Went and bought the proper compression testing kit today and found Alarming results when used :
Cylinder 1 - 4. . . 200/360/240/220

The question I have now is would the engine at least try to start with these readings as at the moment it doesn't even hint at starting up when turning over.
I'll test the injector spray pattern anyway tomorrow afternoon to try and rule them out.

Key said:

Right, checked the valve clearance and all ok, didn't skim the head but replaced head gasket and gave all surfaces a good clean up using 400g wet and dry. All valves were lapped in and confident done properly.
Went and bought the proper compression testing kit today and found Alarming results when used :
Cylinder 1 - 4. . . 200/360/240/220

The question I have now is would the engine at least try to start with these readings as at the moment it doesn't even hint at starting up when turning over.
I'll test the injector spray pattern anyway tomorrow afternoon to try and rule them out.

Click to expand...

Woah! 1, 3 & 4 are way off!

What thickness head gasket did you fit? The same number of holes as the one that came off or did you measure piston protrusion to find the correct size?

When you refitted the head, did you torque the head bolts exactly as described in the manual?

as already said recheck tappets no 9 method ensuring its done when one valve is just fully down and all adjusters look similar after

It had a 3 hole gasket on and I checked using straight edge and feeler Guage and that came up right for the gap. Will recheck tappets using other methods when I get home. Tightened new bolts as described but used one flat of head bolt for the 60 degree turn and then a third of that for the final 20 degree on the remaining central bolts. Is that accurate enough?
Cheers guys.

Key said:

It had a 3 hole gasket on and I checked using straight edge and feeler Guage and that came up right for the gap. Will recheck tappets using other methods when I get home. Tightened new bolts as described but used one flat of head bolt for the 60 degree turn and then a third of that for the final 20 degree on the remaining central bolts. Is that accurate enough?
Cheers guys.

Click to expand...

That doesn't sound correct to me. Or did you mean 60 degree turns?

Do you have the 300tdi overhaul manual?

http://www.landroverresource.com/docs/300TDi_Overhaul_Manual.pdf

Pages 29 & 30.






Finally, and not wishing to sound patronising, are you absolutely sure that the head gasket is on the correct way up?

Key said:

It had a 3 hole gasket on and I checked using straight edge and feeler Guage and that came up right for the gap. Will recheck tappets using other methods when I get home. Tightened new bolts as described but used one flat of head bolt for the 60 degree turn and then a third of that for the final 20 degree on the remaining central bolts. Is that accurate enough?
Cheers guys.

Click to expand...

other methods ?one flat is 60 degrees but you need to do the twice marking which bolts been done each time

I checked clearances using Haynes (1 whilst 8 is open etc) didn't realise they called that the rule of 9 method! Anyway all are spot on.