Please explain injection pump timing

[Travjt]

I bought a new engine because the previous engine suffered from damage. This used engine has less kms on it. Unfortunately someone tool the injector pump off I was told by the mechanic I normally use he is not comfortable making the repair or inspection on the injection timing because he is not a diesel mechanic; I am trying to understand the problem in a better context and understand what needs to be done.

ENGINE TYPE: 2003 Jetta ALH Diesel

Can someone please explain high level but also in technical? terms the how and why, thank you.

 

[Vince Waldon]

Welcome to the forum!

For the right answers to your question you'll need to specific what engine you have... various generation VWs have different injection systems and are timed differently.

 

[Travjt]

Welcome to the forum!

For the right answers to your question you'll need to specific what engine you have... various generation VWs have different injection systems and are timed differently.

Included thank you.

 

[Powder Hound]

It sounds like you purchased a used engine because the one in your car suffered some catastrophic damage, and it would be cheaper to swap engines than try to rebuild. Is this correct? And the replacement did not come with an injection pump. Also correct?

If this is OK, then you should be fine. Well, sort of. Your go-to mechanic not wanting to tackle the swap because he's not experienced with diesels is an honest man. Good for him, and lucky for you.

You do need to find someone who has replaced a pump or two. The replacement engine will need to be installed in the car. Before that, it will probably be easier to install the injection pump as well as a new timing belt kit on the engine. There's a lot more room to work so it will be easier while it is still out of the car.

After the installation, assuming everything is done correctly, you shouldn't have more trouble. The tricky parts to get everything working again will include all the stuff you do for a timing belt change, as well as bleeding the pump and injector lines to ensure there's fuel for the pump to work with. Once the pump, lines, and injectors are bled, your mechanic should then be able to proceed with the final timing checks, initial startup, and then the final timing adjustments with VCDS.

I glossed over a ton of details, but really the timing belt replacement writeups will have nearly everything you'd need to get the whole job done when it comes to technical details of injection pump r&r.

Cheers,

PH

 

[Vince Waldon]

OK, great, an ALH.

If you check my signature you'll find one of the most definitive step-by-step guides there is for changing the ALH timing belt and setting the timing: tools needed, a picture for each step.

 

[Travjt]

It sounds like you purchased a used engine because the one in your car suffered some catastrophic damage, and it would be cheaper to swap engines than try to rebuild. Is this correct? And the replacement did not come with an injection pump. Also correct?

If this is OK, then you should be fine. Well, sort of. Your go-to mechanic not wanting to tackle the swap because he's not experienced with diesels is an honest man. Good for him, and lucky for you.

You do need to find someone who has replaced a pump or two. The replacement engine will need to be installed in the car. Before that, it will probably be easier to install the injection pump as well as a new timing belt kit on the engine. There's a lot more room to work so it will be easier while it is still out of the car.

After the installation, assuming everything is done correctly, you shouldn't have more trouble. The tricky parts to get everything working again will include all the stuff you do for a timing belt change, as well as bleeding the pump and injector lines to ensure there's fuel for the pump to work with. Once the pump, lines, and injectors are bled, your mechanic should then be able to proceed with the final timing checks, initial startup, and then the final timing adjustments with VCDS.

I glossed over a ton of details, but really the timing belt replacement writeups will have nearly everything you'd need to get the whole job done when it comes to technical details of injection pump r&r.

Cheers,

PH

Im going to try to answer your questions in order here from top to bottom

Yes. The timing belt was faulty.. it had JUST9000KM I got the new kit installed with a continental belt on it and damaged the valves and top head estimated repair in my area is about 500$ for the parts excluding the potential bottom end damage investigation. I got an engine with 190k KM on it for 700$ I'm not sure if it was the wild temperature fluctuations that week that contributed to extra stress on the belt or what; I saw the belt it looked pretty evident there was a stress tear.

The engine did come with the injection pump but the engine is out of the vehicle, the timing belt was kind of slapped in there as well which worried him. He's very honest and upfront I love it - the main point he hit on was the "injection timing" could you touch a bit more technically on this part please? I have a fairly good idea of the timing belt, it's housing and it's function - but, the injection timing im not familiar with, the belt runs the pump as well right? then shouldn't it be insync when the timing belt is installed what is there to "tune " on it or cause for concern? thank you

 

[Travjt]

OK, great, an ALH.

If you check my signature you'll find one of the most definitive step-by-step guides there is for changing the ALH timing belt and setting the timing: tools needed, a picture for each step.

Hey, thanks i'm not really comfortable doing this myself yet to be honest because of the potential that can go wrong

 

[Vince Waldon]

No worries... equipped with that guide and following it step-by-step any mechanic with the proper tools and jigs will have no problem safely doing the work.

 

[Travjt]

is the injector timing done through the ECM or manual intervention on this engine?

 

[Vince Waldon]

Set initially using alignment jigs when the belt is installed, and then dialed in by making small mechanical shifts to the IP sprocket's position on the shaft while monitoring the exact value using software.

For further reading, page 110 of the pdf.

 

[Travjt]

Set initially using alignment jigs when the belt is installed, and then dialed in by making small mechanical shifts to the IP sprocket's position on the shaft while monitoring the exact value using software.

For further reading, page 110 of the pdf.

Thank you. Will read that before I bug you again

 

[Vince Waldon]

No problemo... very long document... keep asking questions.

 

[Powder Hound]

Agreed. The basic idea on assembly and getting the timing is that you set the crank and cam to TDC, and lock the injection pump at TDC. No keyway on the cam pulley. Here you have a puller that can loosen the pulley from the camshaft. So the belt can float so the crank, cam, and injection pump can all be locked at TDC, then the cam and injection pump pulleys can be tightened. In this way, the main static timing is set at TDC for all 3 (crank, cam, pump) then the fine tuning can be done at the pump with VCDS.

Bearing this in mind while reading through the install side of the document Vince mentioned will help you keep the forest in view while reading all about each of the many trees.

And also like Vince says, keep asking.

Cheers,

PH

 

[Travjt]

Finally got it running... posting so it may help others; not saying what I did was the best or only way but ultimately it worked.

So.. first off new engine. There is a place in Ontario called Canada Catalyst Inc - VW Parts Store - Auto Recycler. that will sell top-heads for about 350-400 I didnt go with this cause my engine had almost 300,000km on it and just went for a used engine for 700$ CAD with 190,000 KM on it. Dropped in for 700 labour. I had to take it to another mechanic to time the fuel injection, put a new belt on, add fluids, inspect, test for 1k CAD bit pricey but I just wanted a car at this point. The new-er engine I got was sitting for 2 years in a garage. The owner was a mechanic luckily and put oil in the cylinders, the engine started up first-go before the injection timing just a smoke show I have about 300 km total on it now, the engine is great but... I think I lost my stage 1 upgrade ( perhaps someone can confirm this for me or if it stays present in the computer until the demise of the computer) I do have some questions though regarding the old engine if @Vince Waldon and @Powder Hound don't mind...