Reving on its own Diesel.

Post by **Snag20** » 24 May 2008, 16:29

1.6T/D

I have now I believe correctly timed this in at 1mm TDC and cam timing is correct.

Starts very easily and ticks over very smooth and not too smokey.

BUT, when I rev it gently and a only a little bit it tends to take a long time for the revs to drop off.

If I rev it a bit harder it then sems to rev upwards on its own complete with a lot more smoke which is darker and the engine note changes and the revs do NOT drop at all. I can only stop it reving by switching off the engine.

It is a bit smokey from the rocker cover breather pipe but cannot say if it is better or worse than it should be.

I am now at a lost to what is wrong and any suggestions would be gratefully received.

Is it the timing?
Is the pump knacked ?

Is the engine knacked and its burning its own oil ?

please note I bought this as a non-runner/poor starter.

cheers
Trev

Post by **sdelasal** » 24 May 2008, 20:32

try disconnecting the rocker breather and try the test again. If it no longer has then tendency to run away then you know you have an engine which is breathing badly resulting in too much oil entering the intake manifold. If it still runs on then perhaps the turbo is loosing oil into the intake manifold.
Steve

Post by **Snag20** » 24 May 2008, 22:16

Steve,
the rocker cover pipe was disconnected any way as it doesn't fit my replacement rocker cover !!

So I to was thinking knacked turbo seals/piston ring probs.

I too thought it may be consuming/running on its own engine oil. however when I turn off the key it stops straight away which suggests this may not be the problem. But Im really not sure.

I was hoping to drive it for the first time ever this weekend--now not looking to good-- as I really dont know what to do or change now.

Perhaps time for a 1.9 1Y conversion ???

cheers
Trev

Post by **sdelasal** » 25 May 2008, 10:56

Whn you 'rev it' - are you using the accelerator pedal or the arm on the pump? If the cable is worn then it can bind and so not allow the pump to return to ide as fasr as it should. Disconnect the cable at the pump and try reving the engine with just the pump lever. Does it snap back to idle when you release it? Steve

Post by **Snag20** » 25 May 2008, 11:06

I was using the pump lever which returns back nicely ???

cheers

Post by **KarlT** » 25 May 2008, 12:27

Sorry to say I think you already know what it is. Turbo seals. Probably not enough to run engine, yet! But I may be wrong.

Good luck,

Post by **Syncro G** » 25 May 2008, 13:47

How mcuh oil does it use? I'd have thought if it was running on its own oil it'd have significant consumption, so if you don't top it up much theres probubly not much wrong with it. Turbos can spit a small emount of oil into the manifold and it doesn't take much to make it look bad. If your just reving the engine with no load (stationry) the turbo isn't really going to be doing much anyway. Not sure if that'd make the seals more/less likely to leak though.

I notice on another thread your thinking of ditching the engine. Assuming it doesn't breath heavilly out the oil filler, overheat/spit out coolent or make death knocks I think its worth repairing as the main engine will be basicly fine. You'll only be looking at a turbo or injector pump, both are just bolted on - changing one of them for a good one will be cheeper and easyer than an engine conversion and should make a good engine again.

Could be wrong but my gut is if it sounds funny but still shuts down instantly its the pump. In cases I've herd of engines running on oil they needed to be stalled as there was enough oil around for them to run solely on that, though they sound really weard. A quick shutdown once the diesel stops doesn't surgest this.

Post by **Snag20** » 25 May 2008, 18:12

Cheers for ideas,

Glen, I too thought you had to stall an engine running on its own oil !!!Never driven it so cant really comment of oil consumption.

Just an additional thought having looked at it again this afternoon when it eventually stopped raining!!!

On top of the pump is a metal cannister, bit like a mini brake servo. Rubber hose to inlet manifold. I assume a diaphram inside and connected to pump via a pushrod arrangement. What is this, what does it do ?

It appears to be very stiff and the pushrod jams against the side.
It does not move whatever the revs are doing.
I have it set against a screw stop, have now thought is this a tickover stop or a max revs stop ??

please help, dont really want to do engine swap unless I have to but equally dont want to buy bits for this engine if its knacked and replacement pump/turbo wont help.
cheers

Post by **Snag20** » 25 May 2008, 18:14

Sorry forgot to mention it Does puff a bit from oil filler on cam cover, but dont know how much is should or is OK ?

Post by **Simon Baxter** » 25 May 2008, 19:26

What fuel are you running it on?
Does it do it if you disconnect the throttle cable?
The metal can is the LDA, it senses boost and adjust fuel accordingly.
If you think it's slow to return, take the pipe off and give it a squirt of freeing oil down into the canister, it may well be sticking.

Post by **De Konjel** » 25 May 2008, 19:34

[img:600:450]http://i213.photobucket.com/albums/cc18 ... ef900f.jpg[/img]

Do you mean this one

Thats for xtra fuel at higher revs.

On your problem I'm thinking more about piston rings........????????

BART

Post by **Snag20** » 25 May 2008, 20:18

Simon,
Im refering to the metal can that sits horizontaly on top of at the back of the pump.

In its tick over position should the pushrod be pushed into the can or out of the can.

It does not seem to move at all by itself irrespective of the revs the engine is doing. It stays were ever I put it.

It is connected to the top of the inlet manifold by a small bore rubber pipe.

Is there a diapram/ piston type arrangement in this can ??

If its kancked would this give me my symptoms ??

The pushrod appears to be offset in the entry pipe into the can, and is jamming against this when the pushrod is pulled out ?? surely this cant be correct or am I pulling it out to much ??

DONT know what to do next ?

cheers

Post by **Simon Baxter** » 25 May 2008, 22:08

LDA probably won't give you those symptoms.
It lengthens with boost pressure, you are unlikely to see it move much by revving the engine.
yes, there is a diaphragm in the can.

so, what fuel are you running it on?

Post by **Simon Baxter** » 25 May 2008, 22:09

take a picture, post it here.

Post by **Syncro G** » 26 May 2008, 12:47

[IMG:640:480]http://i40.photobucket.com/albums/e224/ ... 8Small.jpg[/img]

The LDA is the thing in this picture with the 4 injector running over the link rod just rearward of it. It does a simular job on other diesels like the one De Konjel shows but as you can see the proper JX van LDA above is an unusual shape. In order to get it to do anything you need to get the turbo to boost up which won't really happen free reving the engine - you'll need to make the engine do some work so that means driving. Just because an engine revs doesn't mean it is/will produice full power, it'll be nowhere near.