New to me 300 tdi pmp

[rodpaslow]

I've got a new pump for my alh and I want to change seal before installing it.  I know they some with a tapered mount for the timing gear and I have to pull this off to replace the front seal.  I'm just wondering how to re-install the timing gear mount.  Since it's tapered, does it need to be pressed on an amount so it stays in place?   Or mark the shaft before removing so you know approximately where it was and press it back on to that mark?  (not talking rotation wise, but length along the drive shaft)

I have one other quick question, what's the best way to drain the coolant in an alh?  Just pull the bottom hose?

[libbydiesel]

You can lock the shaft with the side bolt.  Bear in mind that the LR hub will not work with the ALH sprocket without at least being machined.  Also, the LR pin inserts when the port for the #4 injector on the VW fires rather than the #1.

[rodpaslow]

thanks for that - shouldn't hurt the setup, I plan on using a dial gauge anyway to get it started.  Do you know how much has to come off the hub on the LR pump to have the vw pulley work properly?

I've also been wondering how to get the turbo working properly-although I should have more room to set something up to work the vanes once the cooler and EGR valve are gone.

[william.smith]

Now then!

When I do this I machine the LR hub down to there is 5mm left of the hub. This will allow you to machine the spigot into the hub too - meaning the ALH pulley will centre nicely on it.

Hope that helps.

[rodpaslow]

will do, thanks.

[rodpaslow]

I was wondering how I was going to run the turbo.  I think I'm going to try the dawes-device and keep the vacuum can and see if I can run it manually. 

http://www.chaz.yellowfoot.org/Manual%20Boost%20Controller.htm

above site has both running with the original electronic setup and adding better control with dawes-device and also running a complete manual setup with no electronics interference.

I'm hoping disconnecting electronic pump, (going Mtdi), removing EGR valve,and running the turbo in manual setup above in 2001 ALH, basically keeping everything else connected will not interrupt too much of the rest of the functions of the tach, speedo, door locks, glow plugs, etc.

[vanbcguy]

Running a VNT turbo with just a "boost" can like a wastegate turbo isn't a good idea.  The vanes will be closed basically all the time except at WOT; they're quite restrictive when closed.  It'll make a significant dent in your fuel economy.  When I was building my stand-alone turbo controller I played with opening and closing the vanes a bunch while driving - coasting down a hill you could feel significantly more engine braking when closing the vanes, and that's with essentially no fuel being injected. 

If you want purely mechanical but you want to stick with the ALH stock turbo you need something a bit more complicated; there's a few people on here who have built properly functioning mechanical controls for VNT turbos.  If you want a better (ie more power potential) turbo with less fuss then find a smaller Holset with a wastegate and be happy.

[rodpaslow]

It's not going to be setup as a 'boost' can.  It will be essentially what the ALH already has, minus the electric control valve - n75 I think.  Vacuum will still control it for the most part.  what the dawes-device does is a boost starts, it starts adding air to the vacuum line, essentially starting to back off the vanes.  The sight shows a very linear backing off of the vnt control.  I think for the few dollars I paid for the device, it's worth a shot to set it up and see if it works as expected.  At full boost the vanes are backed all the way off, as no vacuum is present.

[vanbcguy]

Yeah - so all the rest of the time when you're NOT at full boost the vanes will be closed, meaning you'll be choking your engine up.  Your cruise fuel economy will be poor and you'll be working the turbo harder than it needs to all the rest of the time.  You WILL probably have decent control over your maximum boost level, but you'll be running the turbo in a sub-optimal way any time you aren't at peak boost.

[rodpaslow]

I don't know, I'm going to try and and see if it works.  I should be able to tell if its working or not by the way amount of vacuum the control can receives.  If I test it as is (original ALH setup) and see what the vacuum is doing, and then swap over to the LR pump and the dawes device I should see it either react the same way or do exactly as you've described. 

The diagram shows a needle valve as well that will be helpful to set the can to the correct amount of vacuum to start with.  I'm hoping it's going to work as it's much easier.  I don't have a background in electronics, so I can't setup what you have, which is much more precise control.

[rodpaslow]

It looks like the dawes device will keep it at full boost until roughly 10 psi depending on the way its set, it can go lower and of course higher.  Until that time it will be full on.  the needle valve is there to adjust that if needed.  I might mount that so it's adjustable inside the car as suggested.  then if you want to set it lower you can for highway and increase for city, maybe....

[rodpaslow]

It would be nice to setup the needle valve to be adjusted by the throttle cable.

[vanbcguy]

I made a stand-alone electronic controller for my VNT... I keep boost at about 4 PSI at highway cruising speed, the vanes are around 20% closed.

[rodpaslow]

Vanbcguy -  what do you use as the actuator - I understand there's a control box that moves the actuator, but what is actually moving the vane control.  Just curious.  I've read your posts about it, seems to work very well.

[vanbcguy]

I have a vacuum style actuator similar to what would have been on a Mk4 ALH.  There's a solenoid valve that regulates vacuum going to the actuator from the vacuum pump on the engine.  The physical side of things is basically the same as you'd have on an ALH but the electronics are custom.

Yep, it works pretty well.  The electronic actuators can be used too - some of them take a PWM signal just like the solenoid I'm using.  There's advantages and disadvantages to both approaches.  The vacuum actuator provides a little dampening on its own which helps smooth out boost control but the electronic actuators are faster acting.