Bad vibes

[GeoffWillis]

I was hoping someone could help me identify the cause of a REAL bad vibration in my Mod Defender 110, 2.5 n/a diesel. I have recently (Ok it took two years...) rebuilt the injection pump, injectors, put in new clutch/pressure plate, timing belt/water pump, engine mounts and odds & ends. Now, the engine vibrates so badly at idle the vehicle is really not drivable. I cranked up the idle a bit as the vibration eases as RPM goes up. I can't for the life of me figure out the cause of the vibration, the entire vehicle is shaking itself apart. The engine runs great, pulls strong (For a non-turbo diesel...), starts right up, doesn't smoke, everything is good except for the this horrendous vibration. Appreciate any input as to possible causes.
Thanks all,
Geoff

[RoverDover]

I was hoping someone could help me identify the cause of a REAL bad vibration in my Mod Defender 110, 2.5 n/a diesel. I have recently (Ok it took two years...) rebuilt the injection pump, injectors, put in new clutch/pressure plate, timing belt/water pump, engine mounts and odds & ends. Now, the engine vibrates so badly at idle the vehicle is really not drivable. I cranked up the idle a bit as the vibration eases as RPM goes up. I can't for the life of me figure out the cause of the vibration, the entire vehicle is shaking itself apart. The engine runs great, pulls strong (For a non-turbo diesel...), starts right up, doesn't smoke, everything is good except for the this horrendous vibration. Appreciate any input as to possible causes.
Thanks all,
Geoff

-first, Is the bolt on the crank pulley nice and TIGHT? Mine was not, woodruff key got loose,messed with the timing.

-second, If one cylinder is not firing properly it will not run well, but thing improve with revs, loosen the fuel pipe fitting at each injector until it leaks badly, if the engine doesnt run worse or stutter badly, that cylinder is not firing properly or at all. loosen a fuel pipe on a good cylinder and the difference is apparent.

-third, my #4 Hotspot was loose in the head and slapping against the top of the piston as it slowly chewed through the head gasket I wrapped a brass shim around the hotspot, hammered it back into the head and planed the head. Once reinstalled the slapping sound disappeared.

I have all the Land Rover workshop manuals you need for yours and many trucks. If you have an FTP or dropbox, I can hook you up (Free!) I have rebuilt engine, trans,gearbox, axles in my truck with these manuals and never had a single problem, it was like assembling Ikea furniture, but with better instructions. Maybe a video of the idling engine could help us.

[GeoffWillis]

First thanks for the response as I'm stumped on this.
1) Yes the crank pulley is on tight, I even had a special tool built to hold the pulley while I torqued the bolt down to 200 ft/lbs
2) I took it to my mechanic, and he said two of the injectors were not firing, so he rebuilt them. I've not tried the loosening of the fuel pipe to the injectors (Other than to bleed the system after rebuilding the pump), but could try that again. I've heard that that is an easy way to tell if you have a problem with a single cylinder. Have to give that a try when I get back home.
3) I don't understand, what is the "Hotspot"? Is that the glow plug? I do have a lot of slapping noise, but not too bad.
4) I have a dropbox account, would love to have the manuals soft copy. Not sure hot to proceed on this..
Thanks, will follow up after I get home and try fiddling with the fuel pipes.
Geoff

[RoverDover]

A hotspot is also called precombustion chamber its a small chamber in the head that contains the glowplug and injector nozzle.
Combustion begins inside it and continues into the cylinder its the difference between Indirect and Direct injection, TDIs dont have them. PM your Email and I will try to sort out the dropbox thing. This is an open offer to anyone on this forum who wants them. they have saved me a load of cash in the last 5 years. My wife got them printed for me and it filled a 3 inch binder (recto-verso)

[Maryland 110]

what did problem end up being ? I'd suspect timing or faulty injectors.