Lucas CAV injection Pump

[Old Smoky]

There are a couple of guys in the shop who are trying to get an older marine Cummins 6BTA to run. It has been setting for several years, but supposedly ran when removed from the boat. They have got it to fire on starting fluid. The problem is that they are not getting fuel to the injectors. The shutoff solenoid is in good shape, and there is plenty of transfer pump pressure. I am not very familiar with this pump. It has two fuel supply lines. One going to the front, and the other going to the rear of the pump. The only thing I can see is that the front line has bee twisted/pinched, like someone tried to remove it. They other guys think it will flow fuel, but it looks smashed to me. Is the vein transfer pump in the front of the injection pump like the VE? If so, I can see why it won’t run. What is the fuel line to the rear for? Cooling & lube? They didn't seem real ambitious about trying to fix the line unless that is the problem for sure. I think it should be done anyway. Anybody know more about these things?



Mike

 

[JLEONARD]

Mike,

I ran a Perkins T6. 354 for several years and they use CAV pumps. There were 2 bleeder screws on my pump. If they weren't both bled, forget about it.

Hope this helps.

Jay

 

[dzlpwr]

One of the guys at work specializes in CAV (lucas) pumps. He rebuilds the very few that we do get in. I will ask him and see what he says since I am not too familiar with them. Depending on how they have it set up, the line on the top cover is the return fuel line. Pull the fitting off and crank the engine until you get fuel to come out of it. This may take awhile to do if it has been sitting for awhile. The check ball inside the fitting may also be plugged. Be sure that you can blow air through it but don't remove the check ball. It is needed to maintain housing pressures and prevent fuel bleeding back to the tank when shut off. The fuel to the rear is a main line that feeds the transfer pump. It is also possible that your head and rotor assembly is shot and it won't provide full fuel necessary for start, but this usually happens only when the engine is warm. Also be sure that there is not a mechanical shut off too. Some have a shutoff opposite the throttle. The shutoff can also be part of the throttle too so make sure it is pulled toward the full fuel position.

 

[A Johnson]

If I remember correctly you can pull the plunger out of the electric shutoff solenoid and then shut it down with the manual shut off , just like a VE pump. This would eliminate the solenoid for sure. (Its been a while as most marine engine went to an inline pump. )



Also I know the comment about bleeding both screws is a must.



A Johnson

 

[Old Smoky]

Thanks guys. I will relay the information to them.



Mike