My lemons team has just completed installing an OM606.962 into a W123 Pickup Truck. All is well and good except that we've ditched the elecrically controlled pump for an OM603.971 pump. In stock form the DME controlled the injection as well as the wastegate. Oddly it uses PWM vacuum to hold the wastegate shut. We managed to get the car to run and test it's boosting abilities by running vacuum straight to the wastegate, but that just holds it shut and will overboost. I'm looking for a standard wastegate actuator but I'm not having an easy time of it. Not sure what other cars might use the K14 that I can find an actuator off of or if there are any other KKK turbos that might have the same actuator. We'd prefer an off the shelf part to modifying something.
Well the easiest thing to do would be to weld the internal wastegate shut and run an external unit. Second easiest would be to get the vacuum pump working again and use the stock actuator. Third easiest, and by third easiest I mean by the far the most difficult, would be to figure out how to get a pressure actuator to work on a turbo set up for vacuum. The lever arm is set up for a pull type linkage so you would have to grind off the lever weld and turn it 180 degrees so that makes a "C" shape with the valve. Only in this configuration will a pressure actuator work. Then you have to find some pressure actuator that has the right spring in it for the boost you want to run.
1.9 vw aaz’s in Canada came with a k14.
K24 wastegate actuator off of a 1.6td vw would be my go to though. They pop right around 8psi.
Alternatively you could weld the wastegate shut and not run an external valve. Let fueling control the boost. It’s a diesel isn’t it? It’s not like it’s going to lean out. Or is the management smart enough to shut the party down due to overboost.
Are you running vacuum now ? I believe yes but confused. You could use a aquarium valve to adjust the boost ?
Are you running vacuum now ? I believe yes but confused. You could use a aquarium valve to adjust the boost ?
It's running full time vacuum right now. We just plumbed the actuator to straight vacuum to test if it would hold boost. The issue with just a valve is that bleeds vacuum while the factory system went full vac or full atmo to maintain a boost pressure.
Alternatively you could weld the wastegate shut and not run an external valve. Let fueling control the boost. It’s a diesel isn’t it? It’s not like it’s going to lean out. Or is the management smart enough to shut the party down due to overboost.
It's a very small turbo for this engine. During normal part throttle cruising it's at full boost. We're looking to drive it flat out for 24 hours straight. I could see overboosting and overheating come in pretty quickly.
