Thread: Dissapointing fuel pump tweaks...

I'm sure you/ve done it already with all that stuff you have done, but what about checking for air leaks/delamination of the turbo and intercooler hoses...only takes a little leak or blockage to cause a problem

..and is your timing belt spot on.

Hey Jeff,

Wayne is spot on, timing belt should be changed , tappets adjusted and the pump timing set BEFORE any tweaking.

This will give a good benchmark for tuning.

I would also set the pump plunger lift to 1.6mm instead of 1.54mm. Tdi's like this.

This is quite safe and will give you a nice crisp, responsive engine.

FWIW I wouldn't waste $ on the dyno unless you are comparing one mod to another etc, as a comparison they are great, as a tuning tool not as good as 'feeling' the vehicle up your favourite hill.

Just my 2c.


JC

Thanks both - new hoses on when I put the larger intercooler in, and part of the setup on the dyno today was them checking boost (and upping it slighly in fact, so it was back to factory spec) so I'm sure they would have noticed any leaks then.

Timing belt was changed by British Parts here in Perth only 3k ago as soon as I got the car, as the previous owner didn't know when it was last done. So, I can't swear it's correct, but these guys had a good reputation, so it has more chance of being right than not I should think?

Tappets are a thought - I can never tell by ear on diesels as they all sound tappety to me, so for peace of mind, if I can find someone local and reasonable I'll get him to check both.

Only other thing I thought of was injectors - it's done 225k, and I doubt either previous owner ever replaced them, but if it's running OK at the low end, are they likely to be a cause of not being able to get power power out of the top end, and is there any way of checking them?

FWIW I wouldn't waste $ on the dyno unless you are comparing one mod to another etc, as a comparison they are great, as a tuning tool not as good as 'feeling' the vehicle up your favourite hill.

This was done as part of them tweaking the pump, and I wanted a before and after so I knew what the effect was of the new bits. As I said, the car feels more responsive at the low end, and seems to cruise at 100k better, but I was dissapointed with the midrange, as I was hoping larger increases would have been made here. Didn't really care about peak power, though the dyno showed little improvement there too.

all the above, (in a nutshell)

good major service before the pumpers tweak it.

and you can benifit from fitting a "delay" valve to the waste gate diaphragm or by just plain old tweaking of the waste gate.

One thing that lots of pump tweakers forget is as they work the turbo harder they get the air hotter and this introduces a little "diesel" knock which they either

a, back off the timing to fix or
b, back off the pump..


Fitting or at least a thorough cleaning of all the radiators and intercoolers before they play will do wonders, A bigger intercooler is even better, you could even consider an air to coolant intercooler followed by a forced air air to air intercooler..

If your going to that much effort add a pyro gauge, that little puppy tells all as far as diesel tweaks go.

Originally Posted by Blknight.aus

If your going to that much effort add a pyro gauge, that little puppy tells all as far as diesel tweaks go.

Yeah, the one thing I didn't get finished in time...it's in the dash, and the sensor is neatly tied off by the manifold waiting for me to get a tap in the right size! It's also why the dyno tech was reluctant to push too much more fuel through to see if it responded when really tweaked. Once I get that wired up and can see the temp (Or at least get the manifold drilled and tapped so they can stick their gauge in) they'll do me another run.

Shame though, as I was expecting great things based on others experiences...but that's the problem with great expectations - the reality rarely lives up!

Originally Posted by jik22

Yeah, the one thing I didn't get finished in time...it's in the dash, and the sensor is neatly tied off by the manifold waiting for me to get a tap in the right size! It's also why the dyno tech was reluctant to push too much more fuel through to see if it responded when really tweaked. Once I get that wired up and can see the temp (Or at least get the manifold drilled and tapped so they can stick their gauge in) they'll do me another run.

Shame though, as I was expecting great things based on others experiences...but that's the problem with great expectations - the reality rarely lives up!

If your kind about the way you do it, theres no real reason a 300tdi cant be made to make about the same power as a TD5.. I wouldnt personally push one that hard for long but it should be able to do it.

Also pull the top off the pump (noting rotational position of the rod) and check that the fuelling rod doesn't have a 'jelly' build up on it. This is the Defender equivalent of constipation. Full data on tweaking the Bosch VE pumps has been around on this site for a long time; great value as with all things AULRO! My 300Tdi Defender was completely transformed by the basic recommended DIY mods for the pump, plus new silicone hoses for the turbo. Accelerates like a petrol engine, pulls like Hell, not much extra smoke and no noticeable increase in fuel consumption. Did mine about 4 years ago.

Originally Posted by Blknight.aus

If your kind about the way you do it, theres no real reason a 300tdi cant be made to make about the same power as a TD5.. I wouldnt personally push one that hard for long but it should be able to do it.

That would be all I'm after...and even if it was just the improvements it now has in the low end with some more midrange like the TD5, that would be fine too. Don't need a high revving race engine...

What I really need is a decent Landy/diesel mechanic on my doorstep - I'm far more at home with computers and ECU's than good old mechanical fuel pumps and injectors!