renvagn

The car is 89, 951 S, stock with 42K. Two weeks I installed a new stock Bosch BOV. The car was running good. This past weekend a new waste gate was put on. It arrived with an open port (strange) so we called the company. We were told to plug it up. We test drove the car and it was pulling hard as if it were chipped. On the drive home I started to hear very loud (drill like) sound which increased with RPM. It sounds like it is coaming from the left side.

So far no visible tears/cracks in the BOV, its tubing or intake boot. The car has boost but is not what it was. We pulled the waste gate and pressure checked it and it seemed to remain closed until 10 psi. We called the co and were told they should open fully by 7 psi. They also said that the vent opening is suppose to remain open or semi open and that a fitting should have been included. Could this bad information have damaged my turbo, CV and BOV. I am not an expert on the relationship of air/sensors between the KLR, bolt, CV, turbo and waste gate. Thanks.

turbo8

what kind of waste gate

renvagn

Lindsey club sport.

HY M8NC

Lindsey's "Clubgate" works just like the stock wastegate, there is only one fitting at the top which is fed with by a vac. line from the control valve. If that was plugged (as in, the wastegate was just put on the car, and no vac. line was attached to the top) the car would overboost under full throttle. It would peg the boost gauge (I assume you have the factory one) all the way to the right side -2 Bar. There would also be a huge vacuum leak from the cycling valve.

Repeated over-boosting I would think would blow the headgasket. I would look at the coolant and oil levels.

"Drilling sound" has me a little off. I wonder if the diverter valve popped a diafragm? If the diafragm was torn, it would not hold boost, I think you checked that.

What's the boost level now?

OriginalSterm

could over boosting also cause the turbo to blow itself up? may want to pull of the j-boot and inspect the impeller blades on the turbo. i have a bad turbo sitting at home doing nothing and spinning that kinda sounds like a drill i guess.

PorscheDoc

Yeah 'Sterm, I suppose the diverter valve would dump that overboost right into the turbo when he let off the throttle. Would that dump bend the blades?

renvagn

No work on the car today. I will know more tomorrow. The vac line on top of the WG was connected, but there was an additional port on the side which needed a plug as we were incorrectly told. The car still boost but not as strong as it should. We will be looking at the impeller tomorrow and re-installing the WC with a new J boot. I am praying the bad advise on the install did not trash my turbo.
Is the diverter valve the cycling valve?

renvagn

Is anyone aware of the progresion of air as it starts from the air filter to barn door ect. ect. ect.

PorscheDoc

As I understand it-

Air comes in the air filter, and into the turbo. Boosted air runs up to the intercooler, and from the intrecooler to the intake. The diverter valve diverts air back into the J-boot on throttle release. If you are at 12 psi, and let off the gas-that air needs to go somewhere.

There are others on this board who know a LOT more about this than I. The wastegate controls the level of boost, and is opened 2 ways-via a spring, and via vacuum from the CV. I deleted the CV and vac lines under the intake, and went with the Lindsey Racing update kit.

Yeah, if I remember correctly, the top line on the wastegate is vented, the side is where the vac. is routed to. At least it's that way on my dual port Tial, running in single port mode.

renvagn

Just got the word......***T turbo, turbo, turbo! Any ideas on a rebuild? New one? Or going with a ball bearing unit or a bigger one. The car will be mostly street with occassional DE and is all stock and non chipped. I may consider a porsche cup chip however. Any recommendations?

HY M8NC

Oh Man, that sucks....

Alamo sells them new, I've heard good and bad about Majestic Turbo rebuilds. Lindsey Racing and Vitesse have nice products. Or, I suppose you could go used. I would start a new thread and ask the turbo question specifically. Also, use the "search" function to look through old posts-a wealth of info sits there-