CAT 3306 engine starts then dies out - primer pump has resistance B/4 engine starts t

Have the same issue with 3306 in my 140g blade. My filter housing is remotely mounted by #6 hole. When I remove return line from side of pump and cap it I have good fuel pressure and she starts. With line on and everything normal no fuel pressure just dumps to tank and no start. Suspect the orfice is gone in return elbow and there for no restriction to build fuel pressure. Ordered new elbow for today hopefully it fixes issue. Everything before fuel pump has been cleaned and resealed. If new elbow doesn't work only other thing I can think of is transfer pump is weakening/going to ****. Hopefully that's not it and pump doesn't have to come off.

i have a 3306 in a loader and lately the only way it will start is a shot either i put new injecters in and same thing wondering if the plungers in the inj pump be bad ounce it startes it runs perfect

it would seem the above posts are running Sleeve or the big type pumps that both need a rebuild, the constant bleed line is orifice controlled and allows an amount of fuel back to tank to help cool the housing instead of back feeding through the relief valve to the inlet supply, the start with a shot thing sounds like the pump is worn out in the governor case.

i pluged the return line off now it starts is there supposed to be a orfice on return line

taddy said: i pluged the return line off now it starts is there supposed to be a orfice on return line Click to expand... Try supplying a machine Model and Serial Number and the answer might be forthcoming.

cat 966f loader

Nige said: Try supplying a machine Model and Serial Number and the answer might be forthcoming. Click to expand... taddy said: cat 966f loader Click to expand... I see six different flavours of 966F. Got a machine Serial Number.?

966 f series 11 1s100298

taddy said: 966 f series 11 1s100298 Click to expand... See below. The rail pressure relief valve is Item Ref. 3A towards the bottom left of the illustration. Part Number 327-8917.

mine don.t look like like that mine return line cones out behind where the plungers are my lines come off the pump to the injecters

taddy said: mine don.t look like like that mine return line cones out behind where the plungers are my lines come off the pump to the injecters Click to expand... That's what is there according to the machine Serial Number. Do you have an engine S/No.? Can you post a photo of what you have.?

Nige said: That's what is there according to the machine Serial Number. Do you have an engine S/No.? Can you post a photo of what you have.? Click to expand... Nige I think that Serial no. Prefix should be 1SL not 1S1

okay i tried to send a picture but it won.t go through

8V71 said: Nige I think that Serial no. Prefix should be 1SL not 1S1 Click to expand... I figured that out already, but the illustration I posted above came straight from the 1SL Parts Manual.

the other day i pinched the return line off and the fuel pressure went to 80 pounds when i released it it went to 40 pounds now the loader starts whith out either i started it every day and it fires up with no either any body know what the proplem might have been

taddy said: any body know what the proplem might have been Click to expand... WAG air in the system somewhere.? The "pinch off the return line" trick was always regarded as a good way to get an engine started after major interventions in the fuel system to avoid extended cranking on the starter.

you mean its sucking air in suction line

taddy said: you mean its sucking air in suction line Click to expand... It could be. If the problem comes back again in the future then it becomes a distinct possibility.