L300 Leaking fuel injection pump head

ontheebrink · Post by **ontheebrink** » Sun Feb 17, 2019 4:22 pm

My injection pump is leaking through a bolt on the back that connects the pump head. From what I have gathered there is an O ring for the pump head that needs replacing. Is it possible to replace the o ring with out removing the whole pump? Is there anything else I should do while I've got it apart?

One image is regular lighting, the other is with a black light showing the fuel in turquoise. I had to use some tracerline just to find where it was coming from since it blows everywhere when driving. Definitely looks like it's coming from the bottom left bolt.

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deskinthewoods · Post by **deskinthewoods** » Wed Feb 27, 2019 1:08 pm

I just replaced an o ring on my pump without removing the pump. It depends on the o ring I guess. There is a schematic I posted in this thread that might be useful...

viewtopic.php?f=6&t=19116&p=140251#p140251

ontheebrink · Post by **ontheebrink** » Wed Feb 27, 2019 1:35 pm

Thank you. I need to replace seal #2. Hopefully somebody has done it with out removing the whole pump.

ontheebrink · Post by **ontheebrink** » Thu Feb 28, 2019 3:38 pm

I've noticed on other fuel injection pumps most people just back the pump head out enough to access the o-ring and replace it with out removing the whole unit. Has anybody tried this on a Delica?

Post by **Growlerbearnz** » Sun Mar 03, 2019 12:34 pm

The big plug (with the weird 3-sided head) can be removed, and the o-ring replaced, with the IP still on the engine. You don't even have to remove the injection pipes.

ontheebrink · Post by **ontheebrink** » Tue Mar 05, 2019 7:27 pm

I need to replace the larger o-ring behind it. The one on the plate the pump lines attach to.

Post by **Growlerbearnz** » Wed Mar 06, 2019 12:28 pm

Oh. That one's not possible with the IP on the engine. At least, not reasonably.
When you remove the pump head a bunch of things will fall out. The trickiest one to reinstall would be the sliding sleeve on the distributor piston- it has to be engaged with the accelerator linkage, which is usually done by installing the linkage from above *after* you've installed the sleeve.

You could, I guess, take the top cover off the IP while it's on the engine, but at that point you might as well remove the whole thing and replace all the seals at once.

You've seen this pictorial step-by-step rebuild post? http://www.brick-yard.co.uk/forum/ve-in ... 17456.html

ontheebrink · Post by **ontheebrink** » Wed Mar 06, 2019 5:39 pm

I have seen that and it looks pretty complicated, swiss watch complicated, but not unreasonable. If I pull it out I'm guessing I'll have to redo the timing which I am loathe to do. That is what i'm trying to avoid.

Post by **Growlerbearnz** » Wed Mar 06, 2019 7:56 pm

Under the injection pump there's a 2-piece steel bracket that bolts to the engine block. The bracket has slotted bolt holes that you loosen when you're adjusting the timing. If you leave the slotted hole bolts alone, and instead remove the bracket-to-block bolts, you can remove the IP without disturbing the timing. Or, at least, reinstall the IP in exactly the same orientation it was.

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ontheebrink · Post by **ontheebrink** » Thu Mar 07, 2019 4:03 pm

So... Theoretically I'll be able to take it off, replace the seals, and reinstall it with out having to redo the timing? That seems too good to be true.

If I do a full rebuild will it require redoing the timing?

helibrian · Post by **helibrian** » Sat Mar 23, 2019 5:05 pm

Have you been using a fuel additive? I have had my Delica for over 12 years and never had an issue with the injection pump( knock on wood).
I have been using stanadyne lubricity.
I have done the timing belt 4 times. I guess it sucks because it takes around 4 hours to do everything.

Post by **Growlerbearnz** » Mon Mar 25, 2019 1:26 pm

ontheebrink wrote: ↑Thu Mar 07, 2019 4:03 pm So... Theoretically I'll be able to take it off, replace the seals, and reinstall it with out having to redo the timing? That seems too good to be true.

If I do a full rebuild will it require redoing the timing?

Sorry, took me a while to notice this one!
A full rebuild will not change the timing.

Post by **Growlerbearnz** » Mon Mar 25, 2019 1:30 pm

helibrian wrote: ↑Sat Mar 23, 2019 5:05 pm Have you been using a fuel additive? I have had my Delica for over 12 years and never had an issue with the injection pump( knock on wood).
I have been using stanadyne lubricity.
I have done the timing belt 4 times. I guess it sucks because it takes around 4 hours to do everything.

Heh heh. This one comes up occasionally, so here we go:

TL;DR: Diesel made in the USA and Canada since 2005 is fine to use in your fuel pump without lubricity additives. I don't know anything about cold weather additives.

*reads notes from research into this from ages ago*
Right. The "Modern low sulphur fuel = low lubricity = injection pump failure" myth comes from California, where it was fact between 1995 and 2005. In 1995 CA required all diesel to be low sulphur. The process that removes the sulphur also reduces the fuel's lubricity, but CA (and the rest of the USA) didn't have a standard that specified a minimum lubricity for diesel.

Here's a presentation by Bosch (designers of our IP) to CARB in 2003: https://www.arb.ca.gov/fuels/gasoline/m ... 3bosch.pdf
TL;DR: (Read in a German accent) "Your low sulphur diesel is shit. It destroys our injection pumps. Fix it. Preferably by aligning your fuel standards to the EU standards."

The other place where this was an issue was Sweden in 1991, but they fixed it pretty quickly and updated the EU regulations. When low sulphur diesel came to NZ (2003-ish?) we followed the EU guidelines because why wouldn't you.

In 2005 ASTM and CARB updated their diesel fuel specifications to include lubricity. Bosch asked for the same standards as the EU (460um maximum) so of course ASTM specified something slightly worse at 520um. It doesn't seem to cause any harm though.

Chevron's Diesel Fuel Technical Review (https://www.chevron.com/-/media/chevron ... review.pdf) is fantastic, if a bit long. It suggests that Canada's fuel is basically the same as the USA, but with different sulphur content requirements (or maybe just different introduction dates for low sulphur diesel- I didn't re-read it that closely).

Happy reading!

deskinthewoods · Post by **deskinthewoods** » Mon Mar 25, 2019 3:45 pm

That looks familiar!

Post by **Growlerbearnz** » Mon Mar 25, 2019 10:21 pm

Yeah, it occurred to me that since I'd done all that writing, I might as well put it out there