Question about Caterpillar D398 marine engine - 1200 rpm
V12 twin turbo with 2x 6cylinder injector pumps.
Excessive fuel consumption can be ...
fuel leak on to the ground.. Obvious
fuel leak into sump via fuel pump body... Check sump oil
worn piston rings... Grey Smoke
glazed cylinder walls...smoke
burnt valves... Need compressin test
faulty turbo(s)... Sound, check manifold pressures
blocked exhaust line/muffler... Smoke black
faulty thermostat so motor doesn't get up to temperature, what is motor temperature ? ... Smoke black
lack of oil, wrong grade of oil for temperature
scavenge fuel line from injectors blocked or not returning to tank
faulty injector(s) causing poor fuel spray
faulty injector(s) bleeding fuel into cylinders... Smoke black
faulty injector pump balance
faulty injector pump timing
faulty coupling between injector pumps, even can be one 180deg out of timing
bad diesel fuel
Are there mechanical losses in motor load ? Alternator fault ? or gearbox fault prop fault ?
What is the exhaust colour ? Black or grey ?
What are the inlet manifold pressures ?
Using a thermometer ( IR if available ) what are the cylinder head or exhaust manifold temperatures ? This may isolate problem to one or more cylinders.
If you can supply more information I may be able to help track down the problem.
Posted on Apr 12, 2015
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Tips for a great answer:
Apr 03, 2016 | 2003 Honda Civic
Mar 17, 2015 | Cars & Trucks
Jan 19, 2015 | 1999 Hyundai Sonata
Aug 19, 2014 | Cars & Trucks
Aug 15, 2013 | Caterpillar D398 marine engine - 1200 rpm
Aug 15, 2011 | Caterpillar Electrical Supplies
P0174 - Fuel Injection System Too Lean Bank 2 Symptoms - Engine Light ON (or Service Engine Soon Warning Light)
- Excessive Fuel Consumption Possible causes - Intake air leaks
- Front Heated oxygen sensor may be faulty
- Injectors may be faulty
- Exhaust gas leaks
- Incorrect fuel pressure
- Lack of fuel
- Mass air flow sensor may be faulty
- Incorrect PCV hose connection Possible solution Dirty air filter of faulty air flow sensor are common causes of the problem. Bottom line possible defective Mass airflow sensor and or O2 sensor in cylinder bank number two.
Feb 21, 2011 | 1998 Ford Expedition
Feb 06, 2011 | 1997 Hyundai Elantra
Oct 20, 2008 | 1995 Nissan Pathfinder
283 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: