Help - Perkins 4 108

[pdjb]

I have a problem with my boat, I have a Willard 8 ton sailboat, the engine is a perkins 4 108 with an hurth transmission ,but it is reverse. When I bought the boat, some things were not right on ,someone replaced the fuel pump with an electric pump, it failed and didn't know it, I replaced it with the right part, IT ran dry, and I tying to put fuel back into the system, can anyone give information about this problem, since engine and transmission is reverse I can't seem to get to the fuel rail, has anyone had this problem

[glenn.225]

I think you are saying you can not bleed the injectors because you can not physically reach them.


Is this the problem?

[pdjb]

Yes that is right, do you have an answer about this problem

[JPA Cate]

@pdjb, maybe the previous owner put in the electrical fuel pump for a reason?

We installed an electrical fuel pump for our heater to assure a reliable fuel flow to our heater. Maybe your PO's thought process was similar????

Ann

[stormalong]

Are you saying that you have a V drive transmission and therefore the engine is backwards?

I am not sure if you are saying that you restored the mechanical pump or fixed the electric one.

I used to have the same setup - Perkins 4-108, Hurth HBW150V. I did bleed it a couple of times. The mechanical pump lever was very hard to reach.

The bleed procedure on the 4-108 is in the manual. Follow it to the letter. There are a few points that need to have fuel flowing to them in sequence.

If you can't actuate the mechanical pump you could try installing a squeeze ball outboard motor primer pump between the tank and whatever is first after the tank (external filter, fuel pump). That is what I have on the motor that replaced the 4-108.

Be aware that a squeeze bulb is not up to ABYC "code". It should be higher than the tank so that if it should fail minimal fuel would be spilled. Having said that I have had this setup for at least 15 years and it has never caused a problem. It is a great way to fill fuel filters after changing them.

[pdjb]

Yes to everything you said, will post pictures to see what I talking about, thanks

[glenn.225]

There are a variety of tools made to reach hard to get at places. I've used dozens and have made a few.

Here is a couple of samples: commonly called crowfoot.

[Minggat]

The electric fuel pump is a great aid in bleeding the system, over and above the squeeze bulb. You can just turn it off and pull fuel through it with the mechanical pump. It can also just replace the mechanical pump.

Been there.

[onestepcsy37]

what mingat says.

i added an electric fuel pump between the tank and the racor filter just because i didn't like the incredibly taxing process of bleeding the 4-108 fuel system. the electric pump now does it. i never removed the manual pump but could have.

and here's an additional benefit. with an electric fuel pump you now have a built in fuel polishing system. just run the fuel pump without running the engine. the fuel is sucked out of the tank, runs through your racor filter, and is returned to the tank by the injection pump.

[c.K.]

Originally Posted by pdjb

I have a problem with my boat, I have a Willard 8 ton sailboat, the engine is a perkins 4 108 with an hurth transmission ,but it is reverse. When I bought the boat, some things were not right on ,someone replaced the fuel pump with an electric pump, it failed and didn't know it, I replaced it with the right part, IT ran dry, and I tying to put fuel back into the system, can anyone give information about this problem, since engine and transmission is reverse I can't seem to get to the fuel rail, has anyone had this problem

Hey
Last few month I had my 4.108 overhauled in a specialized shop bleeding the lines was a big thing, but I did have excess manual pump can be on the cam so turn the engine slightly
First check the intake at the tank I had a compression fitting there and it was loose so I ground down the nut slightly
then follow the intake fuel line and the manual instructions top of the injectors pump till you see some fuel the bleed screw mid section on the pump
Finally two at the time the fuel lines intake at the injectors bit hard to reach but you can do a quarter turn
Short the starter till you have fuel than go to the next two and repeat
Worked for me

Good luck

[stormalong]

Originally Posted by c.K.

Short the starter till you have fuel than go to the next two and repeat
Worked for me

Good luck

Well, I hope you carry a spare starter. Starter motors should not be cranked for more than a few seconds. They overheat quickly which shortens their life.

I had a 4-108 that was 18 years old when I replaced it. The starter was original. My Beta 50 is now going on 19 years. With preheat it always starts in about one second. Still on original starter.

To crank an engine just to pump fuel is not a very good idea. I knew a lot of cruisers that carried spare starters, especially very expensive Yanmars. An easy starting engine is the best way to avoid replacing starters.

[Boatyarddog]

Originally Posted by pdjb

Yes that is right, do you have an answer about this problem

On the injection pump, there is a bleed screw, if you can reach that, most of the problem will be solved.
Injectors will self bleed.

Please shut off your water flow if you hadn't already.
Hydrolock is not friendly to diesels.
That little electric pump is very handy for the very problem your trying to solve.
Boatyarddog

[marcjsmith]

Originally Posted by Boatyarddog

On the injection pump, there is a bleed screw, if you can reach that, most of the problem will be solved.
Injectors will self bleed.

there are two, one is just under the throttle linkage and from what I understanding very easy to strip/break and very pricey to replace. and the second is on the governor body


TAD has a pretty good write up on bleeding the 4108..


https://www.tadiesels.com/tech-faq.html first tab upper right



its the procedure I followed when waking up my 4108 that sat for 8 years. and also the procedure I used after rebuilding the FI pump.


I just did a filter swap, and I used a small oil vacuum to pull fuel through the filters from the thermostart fuel line. Hopefully by doing this I prevented any air from getting the FI pump.


fortunately on my perk, the fuel filters and lift pump are easy access. Getting access to the FI pump to bleed, well that involved a lot of 4 letter words.

[Boatyarddog]

Originally Posted by marcjsmith

there are two, one is just under the throttle linkage and from what I understanding very easy to strip/break and very pricey to replace. and the second is on the governor body


TAD has a pretty good write up on bleeding the 4108..


https://www.tadiesels.com/tech-faq.html first tab upper right



its the procedure I followed when waking up my 4108 that sat for 8 years. and also the procedure I used after rebuilding the FI pump.


I just did a filter swap, and I used a small oil vacuum to pull fuel through the filters from the thermostart fuel line. Hopefully by doing this I prevented any air from getting the FI pump.


fortunately on my perk, the fuel filters and lift pump are easy access. Getting access to the FI pump to bleed, well that involved a lot of 4 letter words.

I've not used the anti stall device as a bleed port.
AND IT IS NOT RECOMMENDED to do so.
However, thanks for the insight.
Small bleed screw is just right.
Boatyarddog

[marcjsmith]

Originally Posted by Boatyarddog

I've not used the anti stall device as a bleed port.
AND IT IS NOT RECOMMENDED to do so.
However, thanks for the insight.
Small bleed screw is just right.
Boatyarddog

likely not recommended since if its hard to see, and doing it all by feel. Theoretically you could tweak the idle adjustment or the max speed adjustment...I guess...