Engine Room Discussions

[Pampero1]

I bought a pair of these new in 2004...they are the 6 cylinder, 6 liter NA package manufactured as Sabre and branded for Cat as a small 6 cylinder marine unit.  First, they have met and exceeded my hopes; efficient, don't burn a drop of oil, smooth running and plenty of power for my needs; never a lick of trouble.   I have one ongoing problem (stbd unit) and one question.

For several years the starboard motor has been getting "crankier" about shutting down, and with less frequency, about starting.  It started probably just outside my warranty period and has now gotten to the point that I have to go into the ER when IU need to shut her down almost every time. She will of course shut down when I manually cycle the kill lever (fuel cut off?) on the forward port side of the engine. This is located  just behind the throttle linkage and has a red "button" on it.  When I try to kill the engine from the panel by pushing the kill switch there, I can "sense" the closing of the connection (maybe hear a subtle click) but nothing happens down in the hole; the motor continues to run until I manually cycle the switch.

When starting, I can sometimes have a similar event in reverse. That is, I'll hit the start switch on the panel, but not get the starter to turn over.  If I cycle the kill lever, that usually straightens things out for the moment.  

Corrosion? Bad relays? But where and what connections? Manual seems inspecific on this.

Second: Where are the pencil zinks on this thing? Manual (parts and service) doesn't even list 'em and I can't see where they are supposed to go. Good thing the boat is in fresh water, eh? 

Otherwise....no complaints.  They have been just fine...but the no start/no stop issue is getting on my nerves!  

Lew

[JAAS]

  I 've seen this before many times for different reasons, is the fuel system pump a Robert Bosch or a CAV ?

  Let me tell you the fuel system pump in this type of engine is cooled and lubricated by the fuel running inside the pump. With the time moister is created in to the system corroding parts , including the ON/OFF fuel solenoid valve at the back top of the fuel system pump ( both type system pumps ) . This corrosion inside the system pump cause , when you shut the engine off manually , the linkages inside the regulator will not  to come back to max fuel when the engine stop , been hard to start for next time ( specially on CAV )

  I Recommend to  check for properly power supply to the ON/OFF fuel solenoid valve,

Expected : System voltage

  Not OK : check the harness for corrosion at connectors , open circuits and shorts to ground

  OK :     remove the ON/OFF fuel solenoid valve , Be careful not to drop and loose the inner spool Visually check the solenoid valve for damaged set or sticky spool . Then test the solenoid valve providing ground and power supply from a trusted source , it should pull the spool IN when voltage is apply and let go when is remove it .

  If as I suspect you are having troubles with the fuel system pump regulator , then you should schedule for fuel system pump check out and cleaning 

[Pampero1]

JAAS,

Thanks a great deal for your reply.  I gave up on getting an answer and just checked in on a hunch!

I shold explain that it's not hard to start once it turns over but more frequently, won't be killed unless I do it manually at the fuel shut off.\\

Recently it won't shut down on application of the electric kill button at all (and sometimes won't start/turn over as well....that is seemingly less frequent). Once she turns over, she starts right away; it's getting it to turn over (or to kill it) that is the issue. I suspect as you do that there is corrosion on some of the connectors OR a bad solenoid/relay....but in the start circuit that operates the starter solenoid and in the circuit that kills fuel delivery, not the fuel pump itself. Do I make any sense here? 

I will check the pump anyway though for make and model and report back to you. 

[JAAS]

  Hi Pampero1:

  if the engine will not shutoff as we agree there is an open , or a high resistance point at the wiring , must likely at connectors , it include relay , remember this are electrically pilot operated switch and internally the contacts could be corroded , the best way to know this is : disconnecting the relay high current wiring , provide system voltage to the coil , the measure the resistance across the high current contacts, result could never higher than 0.5 ohms , best 0.0 , never  OL or -1 ( depending tool used to measure it ) .

  the same apply to the start circuit , it like when the car engine won't turn over and you found the battery wire was loose .

  Make yourself a favor , clean the batteries post ,and make sure they are tight . The engine and block ground , should be inspected and cleaned , the resistance across any ground anchor to the battery ( - ) must be less than 0.5 ohms , best 0.0 ohms . Also remember at the starter motor there is another relay , that big coil is a high current relay , the contact on that relay may get damage and fail to turn the engine over intermittently , same troubleshot procedure like a regular relay , but in this time you must repeat the activation current several time , just because the inside contactor is rounded and turn free the faulty surface could be on any sector of his area . Some times the best resource it visually inspection.

 Glad to help , keep us posted.

  JAAS  

[Pampero1]

JASS!

Thanks so much! Again, it seems like I am really slow on the draw getting back to you.....good that Cat sent me a tickler! 

I'll get on this this weekend and get back to you....seems like an easy fix.

Lew

[JAAS]

  Pompero:

  There is not problem at it, if you have any doutb , any time ask , but remember the serial number is critical to help you in details.

  Have fun

 JAAS

[Pampero1]

Well it couyldn't have been simpler! ANd as we surmised, just a somewhat "fouled" commector at the shut-off solenoid.

It wasn't inb the actual harness, it was right at the solenid.  A bit of cleaning and a solid reconnection of the connector, and it's all as it should be now!  Very easy fix, as it turns out and even better; no parts required! 

Thanks so much!

[JAAS]

 We are all glad to help you out . Thanks for gave us the opportunity.

  JAAS