Cummins QSL9 parts for sale now from Diesel Pro Power. We have a huge selection of brand-new parts, ready to be shipped directly to you. We have built our reputation on delivering superior quality products that last, and are happy to now offer our products for this engine line. If you have any questions, our friendly and knowledgeable staff are waiting to assist you. Simply call, send us an email or click on chat to get started. Below are some specification of this engine, to help you diagnose possible issues.



What are the general specifications of a Cummins QSL9?

The engine has a displacement of 8.9 liters, a bore of 4.49 inches and a stroke of 5.71 inches. The engine is an inline, 4 cycle, 6 cylinder engine.


What are the specs on fuel pressure?

Diagnosing fuel pressure problems can help you identify the right parts to replace in your fuel system. The maximum allowable return line pressure is 10 in Hg and the maximum static pressure at the fuel pump is 10 in Hg.


What is the maximum allowable restriction to the fuel pump in a Cummins QSL9?

2.5 in Hg with a clean filter or 4 in Hg with a dirty filter.


What is the maximum allowable height of the fuel tank (compared to the fuel pump)?

13.5 feet or 4.12 meters above the fuel pump. Incorrect fuel tank location can put strain on the various parts of the fuel delivery system.


What are the exhaust system specs for the QSL9?

Maximum allowable back pressure is 3 in Hg, maximum incremental direct load at the turbine outlet mounting flange is 20 lb.


What are the air intake specs for the QSL9?

Air intake (and related problems) can cause issues with many different parts of the engine, and should always be carefully examined when considering any engine performance issues. The maximum air intake restriction with a clean filter is 15 in H2O with a clean filter and 25 in H2O for a dirty filter. The maximum air cleaner inlet tmperature rise over the ambient temperature is 30 degrees F.


What is the maximum allowable radial load on the crankshaft?

At angles of 0 degrees and 270 degrees it is 192 lb. At 90 degree angles it is 490 lb. The maximum is at a 180 degree angle, which allows 1106 lb.


What are the engine angles for vessel operation with the Cummins QSL9?

Proper engine angles are very important for the operation of some parts of the engine.

The minimum for steady state operation, engine front up from horizontal is -15 degrees (max is 25 degrees).

The maximum for all drives with intermittent operation, engine roll angle (from right/left when viewed from flywheel side of engine) is 45 degrees right or left.

The minimum engine pitch angle, intermittent operation, is -25 degrees with a maximum of 35 degrees.