G'day Bob / Richard
Just need a clarification on induction leaks relating to question 14 on the timed exam:
A leak in the induction manifold downstream of the throttle in a turbocharged engine can suck outside air into the manifold causing the mixture to become too lean. This condition is most likely during - Answer Taxiing
My question is - am I correct in assuming the above relates to a [u]non automatic waste gate[/u]? If so would this still occur in an automatic waste gate ie leaking into the manifold ? My first thoughts would be no as the upper deck pressure would be equal or high enough to reduce outside pressure coming into the induction...
Appreciate your feedback
Regards
The absolute pressure controller in an automatic waste gate system keeps the ensures the upper deck pressure does not exceed the rated boost. With the throttle fully closed at idle, there is not enough flow of exhaust gas to achieve rated boost so the upper deck pressure would be relatively low. In any case, the question says the leak is downstream of the throttle, so between the throttle and the inlet valves, the manifold pressure would be something like 10"HG. This creates a pressure gradient that allows air to flow into the manifold producing an overlean mixture. This would be the case even for a normally aspirated engine.
Ummm Hi Bob
im really interested in the induction and exhaust leaks sufferd in both automatic and non automatic waste gate systems
My request is dat could i get some detailed information on:
Induction leaks upstream and downstream(if dats possible) of the throttle (induction leaks upstream/downstream of the waste gate)
Exhaust Leaks upstream and downstream(if dats possible) of the throttle (induction leaks upstream/downstream of the waste gate)
Id like to know the possible syptoms(effects) of these leaks (particularly on maintaining Net Upper Deck Pressure and engine Power Output due to these leaks)
It wud really help if i cud get a transparent outlook of these leaks- FOR BOTH AUTOMATIC AND NON AUTOMATIC W/G SYSTEMS
Thanks Again
Rahul 🙂
Yeah Bob, dat wud be amazing :silly:
