Perkins 4107 engine runs for 15 minutes after bleeding, revs up and dies.

[FionaJC]

I have a Perkins 4107 which ran beautifully during test runs ashore before being fitted. It was run ashore with just the engine mounted lift pump and fuel filter.

Now its in the boat I have added a seperate fuel filter and after it an electric primer pump and it then goes into the orininal lift pump then to the fuel filter, both fitted on the engine as shown below and as run ashore.

The engine was bled using the pump and started. the pump was turned off and the engine ran came up to temperature, revved up noticeably then stopped. I bled the engine and the same thing happened again.

1. Is this behaviour likely caused by the the engine sucking in air or airlock in the fuel line?

2. If it is air then could the Thermostart be letting air in?

[GreenWave]

Disclaimer - I am not familiar with Perkins engines...


Are you able to easily restart it after it dies or does it need priming again? My first guess is a fuel delivery problem. Air leak is possible as well. Are you sure your pumps are getting fuel to the engine while running?

[skipperpete]

Hi FionaJC, there’s nothing quite as unsettling as putting an engine in a boat only to have it misbehave at the first startup. In answer to your first question, yes...the problem is very likely on the suction side of the fuel supply system (or contaminated fuel) and the second question.... somewhere between no and maybe, I’ve never liked the “return to filter housing” idea that Perkins uses but the intake heater usually doesn’t cause trouble. Isolate the little pipe connection on the filter to eliminate the possibility completely. I have a few other possible culprits but will leave you to explore the fuel supply first before adding complexity to what’s more than likely a simple suction airleak.... oh, try leaving the electric pump running continuously for your next startup..... and close the raw water intake if you do any extended dead cranking.
Good luck with it.

[Emmalina]

Standard air in the system revving then dying ! Don,t know why you added the electric pump I have seen many Perkins and everybody including myself can prime the system quite happily with the lift pump ! Bleed it all and try again .. Good luck

[Ballsnall]

Originally Posted by FionaJC

The engine was bled using the pump and started. the pump was turned off and the engine ran came up to temperature, revved up noticeably then stopped.

Leave the electric pump running and the issue will go away. Either the pump is restricting the fuel or you have too much filtration restricting the fuel supply to the lift pump. If you keep the electric pump move it to before the filter.

[nhschneider]

I did see a very similar problem with a Perkins 4108 that wound up being a blockage in the exhaust.

Good luck, fair winds and calm seas.

[Madehn]

Almost certainly an air leak. Very unlikely that you have too much filtration. I have a Perkins 6364 with an added electric pump as well. I agree with putting it before the filter. Look at all connections from the low pressure side of the pump back to the tank. Check your oil to ensure that you do not have a lift pump diaphragm that is cracked and leaking.fuel into the crankcase. After that it is a matter of tracking it down. Try running for an extended time with the electric pump on and look for fuel leaks at every fitting. If you have any hose clamps on rubber fuel lines be sure they are sized appropriately and are tight. Too big a clamp and it will not seal welll. Incidentally you can have air ingress without having any fuel leakage. If you have a racor type filter be sure the rubber washer and oring seals at the top of the filter are seated properly and right. Good luck.

[Cheechako]

Diesels rev up when they starve for fuel. Usually I would fit a priming pump before all filters so it's PUSHING fuel through the resistance of the filters, not SUCKING. Pumps push better than suck. But your pump is off when it quits right? I wonder if it creates too much resistance against the engine lift pump?

The last electric pump I installed I ued two 3 way valves so it's completely out of the loop when off.

But beware, your symptoms could also be a clogged fuel tank vent line. Bugs build little nests at the hull outlet!
Is the boat new to you? Another possibility is a clogged pickup tube in the tank.

[c.K.]

Originally Posted by FionaJC

I have a Perkins 4107 which ran beautifully during test runs ashore before being fitted. It was run ashore with just the engine mounted lift pump and fuel filter.

Now its in the boat I have added a seperate fuel filter and after it an electric primer pump and it then goes into the orininal lift pump then to the fuel filter, both fitted on the engine as shown below and as run ashore.

The engine was bled using the pump and started. the pump was turned off and the engine ran came up to temperature, revved up noticeably then stopped. I bled the engine and the same thing happened again.

1. Is this behaviour likely caused by the the engine sucking in air or airlock in the fuel line?

2. If it is air then could the Thermostart be letting air in?

sounds like fuel starvation
in case you have a compression fitting on the fuel intake on tank check if you can twist the connection ( not the nut) i had that problem was easy fix but hard to identify

[Lepke]

I put electric pumps on all injector pump engines I run and have no problems with the pump after the Racor.
The 4107 is sucking air. Somewhere before the lift pump is an air leak. If the engine doesn't stall with the electric pump running, then the leak is probably between the electric and lift pumps. There is no problem leaving the electric on when the engine is running.