Author Topic: Whats this? (Read 15317 times)

QuickTD · « **Reply #15 on:** June 13, 2004, 05:42:36 pm »

The screw in the middle of the LDA cover is used to set the base position of the control cone. It's a nice tuning feature, makes it easier to tune the "off boost" smoke, but not mandatory.

When you remove the cover the cone will push up under spring pressure. Not a huge heavy spring or anything. You probably should avoid actuating the throttle while the LDA cone is out. If you do the "follower" pin will slide out into the LDA cone bore and make it impossible to reinstall the cone. If this happens you will need to stick a small screwdriver or pick down the LDA cone bore and push the follower pin back in toward the belt end of the pump, not a big deal. It can be a bit tricky to get the flat sided LDA pin back into the bore facing the right direction (flat towards the belt). It wants to rotate as the spring compresses. Marking the diaphram with white-out or a paint marker helps. With an eccentric cone LDA pin this is somewhat less critical.

The lack of a star wheel can be a bit of a problem. I would recommend that you use the 1.6TD spring and use shim washers or machinery bushings to shim the spring up. I can't remember exactly how thick my current stack of washers is, somewhere around 1/4" would be a good starting point. The 1.9TD spring is very long and pretty much constant rate. The LDA is either on or off with this spring. Not very linear and makes for a smoky setup. I wouldn't recommend using it.

type53b_gtd · « **Reply #16 on:** June 14, 2004, 08:36:21 am »

Excellent information, QuickTD - many thanks. Now I'm keener than ever to get working on this 94. One more question - on my 94 (with AC) there are two vacuum valves - one by the air filter - I assume this is the changeover valve for EGR/boost control, and the other up by the fan control module - I assume this is related tp A/C operation (possibly A/C idle boost?) My 97 did not have A/C and only had the one valve by the air filter.

Drew

QuickTD · « **Reply #17 on:** June 14, 2004, 07:23:16 pm »

Mine ('97 w/AC) actually has 3 solenoid valves. Two are located on the right strut tower, one is the "changeover" valve, the other is for the AC idle boost. The third one is up on the firewall near the brake booster, it controls the recirculation flap on the heater box.

type53b_gtd · « **Reply #18 on:** June 15, 2004, 09:16:00 am »

I only have one on the strut tower, and one by the booster. There is a dashpot on the pump, and the car does have A/C. It also has cruise. Does the cruise use the dashpot that would otherwise be used by the idle boost? If so, you'd think it would be connected to the main llinkage on the pump, not the idle boost linkage.
Drew

QuickTD · « **Reply #19 on:** June 15, 2004, 09:24:23 am »

The cruise actuator is located under the dash and presses directly on the pedal. It's controlled by a module located inside the left fender.

I'm guessing that you are missing the changeover valve. If yours is a 94 it may not have the wastegate opener setup on it. I've even seen some early models (93-94) that don't have a K03 turbo. Some use a K14 that does not have any provision for pulling the wastegate open with vacuum.

type53b_gtd · « **Reply #20 on:** June 15, 2004, 09:49:37 am »

Quote

The cruise actuator is located under the dash and presses directly on the pedal. It's controlled by a module located inside the left fender.

Well who would have thunk it?

Quote

m guessing that you are missing the changeover valve. If yours is a 94 it may not have the wastegate opener setup on it. I've even seen some early models (93-94) that don't have a K03 turbo. Some use a K14 that does not have any provision for pulling the wastegate open with vacuum.

Yes, the turbo is definitely the earlier one - the compressor hose from the turbo outlet to the intake is a larger diameter than the one on the K03. Although I haven't removed the turbo yet, I'm expecting it to be a K14. Is there a significant difference between the two turbos?

Drew

QuickTD · « **Reply #21 on:** June 15, 2004, 09:33:24 pm »

The K14 is a larger turbo than the K03 but still smaller than both the 1.6TD garret or K24. It actually has more in common with the K24 from the 1.6TD than the K03. It uses the same type of wastegate and manifold flange. I would like to find one of these turbo's for my 1.9TD. I think it presents the best compromise between quick spooling and high boost/flow efficiency.

type53b_gtd · « **Reply #22 on:** June 16, 2004, 08:43:47 am »

Quote from: "QuickTD"

I would like to find one of these turbo's for my 1.9TD. I think it presents the best compromise between quick spooling and high boost/flow efficiency.

Outside of VVG/VNT, you mean?

The jury is still out on which turbo I use on this engine, although based on what you're saying the K14 may be a better choice than the K03. I don't spend much time up above 3K on my Scirocco's 1.6, and I'm pretty satisfied with the K03. However, that's not stopping me from attempting to fit a VNT15 to it as soon as I get this Golf on the road.

If I do end up not using the K14, I'd be happy to discuss selling it.

Drew

QuickTD · « **Reply #23 on:** June 16, 2004, 08:50:52 am »

Quote

Outside of VVG/VNT, you mean?

Naturally...

I would go with the K14. If you don't use it, and are interested in selling I'm fairly local...

If you happen to stumble across a few inexpensive VNT15's in your travels I'm also interested. I think they could be "perverted" to operate from boost pressure rather than vacuum.

type53b_gtd · « **Reply #24 on:** June 16, 2004, 09:10:04 am »

Quote from: "QuickTD"

I would go with the K14. If you don't use it, and are interested in selling I'm fairly local...

If you happen to stumble across a few inexpensive VNT15's in your travels I'm also interested.

I have 3 of them - one is pristine with less than 1000km (that's destined for the Scirocco) and the other two are both of higher mileage and unknown condition. Actually, I believe one of the two has a seized actuator.

Quote

I think they could be "perverted" to operate from boost pressure rather than vacuum.

This is my suspicion as well. The actuator cannister that has a vaccuum connection to the N75 has a capped port on the opposite end of it - which suggests to me that applying manifold pressure to the other end of the diaphragm may achieve similar results...

There were a limited number of 90/91 Dodges with VNT25 that were boost controlled IIRC.

I don't know about mounting the VNT15 with integral exhaust maniofold on the A2/A3 chassis though - it seems to me that the rear passenger's mount would be in the road? The nice thing about the A1 is that there's no mount in this location. It seems to me that RedRotors acquired a VNT from Europe that had a separate manifold to avoid this issue on his A2 Golf?

Drew