Perkins 3.152 engine fuel problem?

I have a Lincoln 400AS diesel welder with the Perkins 3.152 engine. Bought about eight years ago and welded with it satisfactorily during that time. In the last couple of years not used too much but welded with it successfully three weeks ago. Started it yesterday to give it a run but not for any welding. Checked engine over while running and noticed liquid bubbling from sump dipstick but oil pressure was ok. Then saw liquid flowing from breather hose attached to tappet cover as well. Shut down and checked engine oil level which dipstick showed overfull but thin oil. My conclusion is oil getting diluted with diesel fuel somewhere and most possible and probably easiest fix is through the lift pump. The fuel tank is above the lift pump with no fuel tap fitted but the fuel line is attached the the end of the tank so not a direct drop. Possibly the lift pump diaphragm has split and pumping fuel into the crankcase so maybe later today I will remove lift pump for inspection.
These are common diesels and this one would date from the 1970s so welcome any comments or advice from anyone who has seen a similar problem.

Give Mick Umback a ring.. he's forgotten More about Perkins than the rest of us combined will ever know..!!

I reckon your well on to it with the lift pump diagnosis

Cheap and simple to fix

Paul

Sounds to me like the lift pump diaphram. Put a kit through it but do yourself a huge favor fit a fuel tap while your there and fit a sign turn fuel on/off near the key switch.

Thanks everyone who offered suggestions. I removed the lift pump this afternoon and disassembled it after a clean up. Unfortunately even under magnification the diaphragm looks all right. Of course the diaphragm may have a defect that is only apparent when pumping. Maybe a kit will fix it but in any case I will call the Rock Tractor Service as suggested by hayseed after the NY break to see what they suggest and order any necessary parts. Will attach some photos of the pump below.

The seal on the DPA injector pump shaft may be cracked after 50 years too.......the mechanical DPA doesnt have much pressure inside the body ,so it wont fill the motor while its running like the hydraulic DPA will.

I'm with John K here. More likely the seal in the DPA pump. Still not a hard fix.

Thanks to John.K and wee-allis for their conclusion. I had hoped it would be something else apart from the distributor injection pump but now realize the amount of fuel inside the engine in about 10-15 minutes running must have been caused by high pressure and high flow. Never removed an injector pump but have a pda manual for this engine so I will follow the instructions. Should have a clean engine inside washed with diesel so will drain sump and use new oil before any restart.

Ive had two motors where diesel ran out the dipstick .....the Massey Ferguson drott always had bad oil pressure,but problem was I couldnt find the fuel pump........It was buried in 2 cu yds of dirt on top of the motor,the whole V of the motor was full of dirt level with the rocker covers.