SVO Mishap #1 - Injection pump overhaul

[mike_ie]

Well, my adventures with vegetable oil as a fuel have met a fun roadblock today - I was playing around with the heat exchanger and forgot to turn back on the coolant taps, and as a result I think I have fried my injection pump.

I've gone through the fuel system step by step, and the lift pump seems to be working, fuel is passing through the diesel filter (which has been replaced with a new one), and is getting to the banjo fitting on top of the injection pump, but nothing is coming out to the injectors. After ringing around, I can get a secondhand injector pump for about $650 - a sigh of relief in a way, considering that I thought I'd be paying a four figure sum for my screw-up, and I'm willing to give changing out the pump a shot by myself. So, I have a few questions for those with greater knowledge than myself...

1. Seeing as I'll be pulling out the old injection pump anyways, is it possible to overhaul these things? Is there anything that could be blocked, or clogged with oil?? Is there a chance that this thing may be fixable??

2. How much fuel should the lift pump be pushing through?? Fuel is going through the system, but I'm not sure if it's enough. If the lift pump wasn't pushing through enough fuel, would this stop the injection pump from working??

3. How much work is involved in changing the injector pump?? I understand that the injector pump timing has to be set correctly - how difficult is this to do? Do I need any specialised tools for the job??

4. Have I forgotten anything???

[abaddonxi]

Is there a gauze filter under the banjo on the fuel injection pump? Have you cleaned the guaze filter on the top of the lift pump. Was the old fuel filter clogged up? Have you cleaned out the sedimenter? Have you checked for sludge in the tank?

If you've got crud from the wvo then it's going to be through the whole system.

I had a new one shipped from UK for about $1600, I was quoted about $1200 for a rebuild on the old one.

Simon

[Bazzle218]

I had a 300tdi running on SVO with no problems. I plumbed the heat exchange into to heater pipes with no taps and no problems at all. The water ran through it all the time and caused nil issues. Running on SVO or Diesel. I agree with other posts check the filter under the banjo bolt.

[mike_ie]

Is there a gauze filter under the banjo on the fuel injection pump? Have you cleaned the gauze filter on the top of the lift pump.

Nope, and nope. For the simple reason that I didn't know that there were filters there. However, fuel is getting to the injection pump, therefore I can assume that the lift pump filter is not blocked.

Was the old fuel filter clogged up?

It didn't seem to be. However, as a precaution (and because it was due a filter change anyways), I put in a new one.

Have you cleaned out the sedimenter? Have you checked for sludge in the tank?

Yes I have. I've also drained the tank and filled it with fresh diesel.

I had a new one shipped from UK for about $1600, I was quoted about $1200 for a rebuild on the old one.

I got a quote today for $650 for a secondhand one. Guess I should count myself lucky??? Did you install your replacement pump yourself? Any issues??

[isuzurover]

As the others have pointed out, catastrophic failure of the IP is highly unlikely. The Bosch VE pump tolerates SVO well - even one-tank systems.

Maybe try heating up the IP (gently) with a propane torch or similar to clear any blockages.

[mike_ie]

I absolutely hope that you are right - an injector pump replacement is certainly something I can't afford at the moment. What's worrying me though is that for about an hour beforehand there was a constant ticking sound coming from the engine. I didn't think too much of it at the time, but reading varios posts since, it seems to be a symptom of a failing injection pump.

[isuzurover]

If it is dead it may be unrelated. Some versions are known for the case hardening flaking off and killing the pump.

If you remove the fuel cutoff solenoid you should be able to see if there are any metal flakes in there.

I personally would be wary of buying a SH pump with unknown history. A rebuild shouldn't be much more than 1K if you shop around.

All the above is assuming the pump is actually dead.

[abaddonxi]

Another problem with older pumps - pre-96 - is that they might not have viton/vitron seals - wvo resistant.

Simon

[mike_ie]

and another problem might be the person servicing it . As it turns out, it was the fuel cutoff solenoid that was faulty, and thankfully a much cheaper fix than an entire injection pump. But there's always a silver lining - the money I would have paid for a pump is now going towards some toys that I wanted to get for quite a while. so win, win situation

Thanks for all the suggestions - much appreciated.

[isuzurover]

and another problem might be the person servicing it . As it turns out, it was the fuel cutoff solenoid that was faulty, and thankfully a much cheaper fix than an entire injection pump. But there's always a silver lining - the money I would have paid for a pump is now going towards some toys that I wanted to get for quite a while. so win, win situation

Thanks for all the suggestions - much appreciated.

Good to hear. No shiny bits when you removed it?