K Jet DX Engine not starting

[bmouthboyo]

Hello,

I appologise in advance for this long post but the more info I give hopefully will enable me to fix this.

I bought a T25 camper van 2 years ago from eBay in a poor state but running. It had been sat off road for 5 years prior. It had previously had engine replaced with a K-Jet DX engine (Mechanical Injection) of which I know very little about.

I did some engine work such as replacing manifold (complete b*tch!), new head gasket, head skimmed, plugs, oil, filters etc. This was about a year and a half ago now and after all the work the engine started up, sounded a little rickety but to be expected without being used properly for so long. I then had a problem with the coolant system, non engine related and when winter came it kinda took a back seat for a year.

This summer I tried to start it but it just wont start, even though nothing has been tampered with since last year when it would. It cranks over and occasionally splutters but without help adding more fuel to pistons just cranks over and doesn't even seem to be trying to fire up.

If I manually lift the metering flap, fuel does come out of the injectors (albeit one seems temperamental in its spray pattern) so fuel is being delivered. If I manually lift the flap with the air hose housing off the metering head I can hear the screech of the k-jet injectors, if i then try starting with hose re attached it kind of splutters a little but wont fire up. It seems the manually added fuel helps but doesn't start it.

I am thinking it must be one of these:

• Intake hosing not air tight and loosing suction needed to lift metering flap correctly
• Metering head needs attention / calibrating as too much resistance to lift flap
• Injectors need replacing / not delivering fuel consistently/equally
• Coil needs replacing? (old)

My main reason for posting is firstly to see if I am on the right track, and also receive any advice on what I should be checking / replacing and in what order.

Any help much appreciated, Thanks

[rubjonny]

try cranking it as you manually lift them metering head flap, if you're good you can get it to run for a bit like that 

this will rule out fuel delivery, and then you would move onto issues with the intake system and 5th injector. does the 5th injector spray fuel when it cranks over for a few seconds when stone cold?

next check the flap in the meterin head is flush with the narrowest part of the code at the front edge (i.e. edge closest to the fuel metering part).

Oh and other thing, is the metering head 100% level,?

[bmouthboyo]

Hey Rub thanks for replying.

I have not actually tested the 5th injector yet but will do when I get the van to my new place next week.

I have a few questions if it's ok to run by anyone.

Firstly my K Jet DX engine has what looks like custom (DIY) fuel lines going from the metering head to the injectors. It feels rigid/solid like a brake pipe, could these be replaced easily with braided ones?

Am I right in thinking that I could replace the injectors if faulty with Mercedes Bosch Injectors like this [url]http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=360271404659&ssPageName=STRK:MEWAX:IT[url]

Secondly to test my K Jet system I am assuming I would need a fuel pressure tester. Can anyone point me in the right direction of a cheap option that will work with my setup?

For reference this is what engine looks like. Sorry state I know

[rubjonny]

if you can get lines the right length then yep you can use flexi braided ones. trouble with yours id the metering head is miles away! 16v might work the early ones come with braided lines and the later 16v have hard metal lines which with careful bending may be adaptable to your bay?

the mercedes injectors will only work if you have the coarse thread injectors on there, the later 8v and 2.0 16v had a finer thread pitch. mk2 16v likes are all coarse thread though, another reason to possibly go for them if they'll reach

[bmouthboyo]

OK so my van is now at my new place so more time to sort problems with this non staring engine.

Today I did the following:

• Checked inlet hose for any cracks allowing un-metered air in
• Swapped metering head with another I had laying about
• Removed injectors to test spraying
• Removed 5th injector to test spraying

I swapped the metering head first of all as the cylinders looked stone dry when cranking. There is definitely pressure their, fuel in eye to prove it lol!

With the other metering head on It still would not start, however lifting the flap manually and cranking would cause injectors to spray a pretty healthy amount (flap 95% open).
See Vid>>>http://www.youtube.com/watch?v=blyxMN28bow

I will check them for volume and cone etc soon but at least they are delivering some fuel. However with the inlet hosing attached the natural suction pressure of the engine on crank is not causing them to deliver at all. Is this normal?

I checked the 5th injector. Not spraying on crank. Fuel is being delivered, high pressure when undoing fuel line to it.
Bridged the terminals on the Thermotime switch. Still not spraying on crank.

Now my problem is that someone who had the motor previously has done a very DIY job on the wiring. As a result the wiring does not use the fixings on the loom and instead he has added his own with spades. Why, I do not know. However when I last had an auto sparky do some work he rewired a little so it needed a fuel pump relay as whoever had it before had wired it to a switch (guessing couldn't be arsed / afford a relay) that manually turned the pump on and off.

This is how the cold start injector is wired in my motor:



I have no idea if it's right, but bridging the terminals going to the thermotimer is meant to make the cold start spray on crank but it is not. I am going to buy a mulimeter and learn how to test the current to see if its the injector, but my guess is it's the shoddy electrics.

Sorry for long post. So questions:

• Should the main injectors spray with the engines natural suction on crank?
• If so would a faulty cold start injector cause them to not spray under natural pressure of crank as it needs that little fireup the 5th causes?
• Is the wiring in my diagram wrong?
• Any advice on what to test next?

Thankyou for all your help

[danny_p]

get a plug on thecold start injectors and give it 12v direct from battery when crancking,  that'll get it going if not it's spark

[bmouthboyo]

I am completly new to electrics. How would I get 12V? 2 terminals on one of those rectangle batteries that go in toys etc?lol

[SoundillusioN]

I am completly new to electrics. How would I get 12V? 2 terminals on one of those rectangle batteries that go in toys etc?lol

You just need to bypass the Thermotime switch as this is interupting the feed... another small point, currently my 5th injector is out of action and although the car may take slightly longer to start when cold, it still starts fine, even in minus temps it starts without it.  I don't think the 5th injector is your main problem.

[bmouthboyo]

I did bypass the thermotime switch and nothing, I am checking if the DIY wiring is correct. I'll eleminate teh cold start valve then go from there. I swapped the metering head and if I manually lift the flap it does deliver fuel (see video above). I am not sure why the engines crank suction pressure is not enough to life the metering head to give even a little fuel.

Not sure where do go from here

[SoundillusioN]

I did bypass the thermotime switch and nothing, I am checking if the DIY wiring is correct. I'll eleminate teh cold start valve then go from there. I swapped the metering head and if I manually lift the flap it does deliver fuel (see video above). I am not sure why the engines crank suction pressure is not enough to life the metering head to give even a little fuel.

Not sure where do go from here

I would have looked at vid but cant at the mo as at work.... you've defo got a spark?