Logo
FULL SITE MENU

Life span of TBI's and sensor components

G

gofastpilot

New member
Is 1000 hours still considered "young" for stern drive engine ? I know this depends on how it was treated and maintained but let's say a pair of 5.7 EFI's sitting in a heavy cruiser that rarely leaves the dock, gas sits in the tanks for a whole season, engines get run once a month for a "cruise". Can we say a engine sitting doing nothing is an "abused" engine? What's the life span of TBI injectors? Mine are pushing 28 years old. Yeah they still spray fuel but do the nozzles "wear" with age. Seems they really run overly rich when cold (75 F). I understatnd there are diaphrams (rubber) that are incorprorated into fuel pressure regulation. Should fuel regulation replacement be the first line of defence when maintaining these engines. Throttle bodies on 5.7 engines actually are marinized 454 GM throttle bodies go figure why oil gets diluted till the engine fully warms.
 
When I worked in the shop, we used to use the general rule of 1000 hours for the top end service life and 2000 hours for the bottom end, assuming decent maintenance and no abuse. Sitting isn't good for an engine and running the engines in the slip isn't either.

Injectors will last a long time. Yes they will experience some wear but its minimal until you get into the thousands of operating hours...most suffer from build up due to lack of use.

I don't know of anyone that routinely changes the fuel pressure regulator as routine maintenance.

If the tune in the ECU matches the injectors used and the fuel pressure supplied, the original application for a TBI unit shouldn't matter. it wouldn't be a bad idea to scan the ecu, while running, and make sure the data provided makes sense...sometimes sensors fail (loose accuracy) and never trigger a DTC...
 
Other life impacting factors"
1) If in salt water, raw water vs heat exchanger cooling.
2) When ran was cruise ( continuous operation) limited to 80% of MAX RPM @ WOT
3) Correct prop, i.e. was engine able to rev up into the mfg specified MAX RPM range with normal
load of passengers, gear and full load of fuel.
 
Back
Top