Fuel lift pump heads up

Just wanted to let some out there know something I discovered y-day who may not already know. My Perkins 6.354 has a manual primer lever on the lift pump. Y-day we tried to go out ant it stalled-luckily we were still in our canal system so we just drifted over and tied off to a dock. I had very little warning that something was wrong, the engine rpms climbed and dropped a little several times like a filter clogging. I pulled my filter which was pretty clean. cracked an injector line and primed via the manual lever. Engine fired and ran a minute or so and died again. I cracked lines and hit the starter---no fuel! The lever could make some pressure but the engine operated lever didn't move it enough to pressurize anymore. Luckily my boat's cruising bag had a spare lift pump! I changed it out and the manual lever even had a drastically different feel. Needless to say-she fired right up and ran fine all the way back home!!

Just because the manual lever will move fuel--don't assume the lift pump is OK

Do you know what part failed on the pump?

That fuel pump has two areas of common failure. 1 - a pinhole leak in the diagphram
2 - there is a little rubber grommet on the fue- in line that is accessed from inside the pump. This grommet can swell over time, choking the fuel as the rubber warms up and expands.

You can buy the grommet (looks like a rubber tube) at any diesel shop. You can also buy a rebuild kit for that pump but its not much of a saving over a new pump. Good idea to have a spare in stores.

I haven't pulled the pump apart-tomorrow. New pumps run anywhere from $45+shipping to +/-$80. I've only found 1 place still stocking rebuild kits and they are only $14. Once I break it down tomorrow I will decide whether to order a couple of rebuild kits or just get another "Perkins" pump. They are $56 from TADiesels.
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And yes there are a few things that are reasonable to carry as spares that you can't "limp" home without. While I could likely have pulled all my filter elements out of the system and the injector pump could likely have pulled enough to get me home, I still highly suggest having a lift pump in your spares esp when you consider their cost and the room they require in your spares storage area. I don't know about the rest of you but I know my tanks have a bit of algae floating around and if possible I'd really rather not run that crud through my injection system if I can avoid it just by replacing this pump (4 bolts and 2 line fittings).

Couldn't resist the HEADS UP. My Ford Lehmans use the same lift pump as Perkins and I bought spares from the Perkins dealer here. I also had a failure with one while out. On the way to Catalina my starboard started slowing and speeding up. I made it to a mooring and it ran fine. I suspected a filter and my inspection found them clean.

I had 9 people onboard for a short cruise and left the mooring and made it out to open sea when it quit. After troubleshooting, moving the arm and disconnecting the fuel line, I found it not working. After replacing it with a new spare and bleeding the air, I fired it up. The engine was hot too.

I took it apart at the dock later and found the lever had become disconnected from the diaphragm. A small piece was moving around inside it and when it came between the arm and diaphragm it would pump.

Capthead said:

After replacing it with a new spare and bleeding the air, I fired it up. The engine was hot too.

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LOL yeah ain't it funny how they never seem to rear their head when at your home dock, while its warming up, and your messing around getting ready to cast off. Its only after coming up to full operating temp and essentially becoming a #1200 heat sink! And to top it off, on my boat I had to lay down on the heat exchanger!!! to reach it.
I want an engine room on my next boat

Remove our mechanical lift pump on our Perkins and switched over to a Walbro electric around ten years ago, no problems. Sure makes changing fuel filters easy as an added bonus.

boatpoker said:

This grommet can swell over time, choking the fuel as the rubber warms up and expands.

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Rubber, like many polymers, shrinks as it warms up.

That's why your loose fan belt stops squealing after it gets hot from slipping ... it shrinks and is too tight to slip.

twiisted71 said:

I've only found 1 place still stocking rebuild kits and they are only $14. Once I break it down tomorrow I will decide whether to order a couple of rebuild kits or just get another "Perkins" pump. They are $56 from TADiesels..

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Who had the rebuild kits?? My supplier no longer carries them.

LB

Edelweiss said:

Who had the rebuild kits?? My supplier no longer carries them.

LB

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For these old engines ya gotta go outside the box sometimes. They were used in everything from OTR trucks to forklifts. Massey Ferguson tractors used loads of 6.354s so keep them in mind when looking for non marine specific components.

4222110M91 1882944M92 - Discounted all Tractor Parts Catalog

Anybody have part #'s or links to either mechanical or electric lift pumps for the Perkins 6.354? It sounds like a very good item to keep in spares!

I hope this doesn't get too religious, like anchors, thrusters or twin engines, but anybody else have some pros and cons about electric lift pumps? Sounds like it might be a good upgrade.

And thanks for the heads-up! I'm no diesel mechanic, but I've helped out on a lot of repairs. Never a lift pump failure though, so that wasn't on my radar.

CaptTom said:

Anybody have part #'s or links to either mechanical or electric lift pumps for the Perkins 6.354?

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Take a look at these offerings. You can install one inline before the lift pump (fuel will "suck" through it when it is unpowered) or as a bypass to the mechanical lift pump.

OEM Products - Facet Purolator

They are always available on eBay at very reasonable prices .

I used a Walbro 6000 series 15 years ago, this has now been replaced with the Walbro FRB-13 Fuel Pump. Guess I should order a new one for a spare.

When the PO updated the fuel tanks, he installed this fuel pump (#6 below) inline before the Racors. They were never wired in, but they run with 12V supplied. Last time I replaced the filters, I powered the pump with a jump start battery pack and it made bleeding the system a breeze.

It's nice to know they're there if or when needed.

I have used a Walbro electric fuel pump to fill the day tank for my Diesel stove, for 20 years. I have had 2 pump failures in that application, which gets little use, since the engine return line does the heavy lifting.
On my Onan 4 kw genset the fuel is delivered by an electric pump. It too has failed on an engine that gets little use.
I have never had a manual lift pump failure.
Just sayin....

RickB said:

Rubber, like many polymers, shrinks as it warms up.

That's why your loose fan belt stops squealing after it gets hot from slipping ... it shrinks and is too tight to slip.

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Sorry Cap'n RickB- the reason your fan belt stops squealing after it warms up is that the alternator load has reduced after it replaces the voltage used from the battery when starting. Less load, stops slipping.
I'm always amazed at the guy at the Circle K who cranks his Ford pick up, belt starts to squeal, he begins to race the engine (convinced this is the cure), alternator demand lowers, squeal stops, and he backs out, convinced he's figured out his to make it go away .

koliver said:

I have never had a manual lift pump failure.
Just sayin....

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Yup, my experience too.

Forkliftt said:

Sorry Cap'n RickB- the reason your fan belt stops squealing after it warms up is that the alternator load has reduced after it replaces the voltage used from the battery when starting. Less load, stops slipping. I'm always amazed at the guy at the Circle K who cranks his Ford pick up, belt starts to squeal, he begins to race the engine (convinced this is the cure), alternator demand lowers, squeal stops, and he backs out, convinced he's figured out his to make it go away .

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If the belts on your alternator is squealing from that kind of load just from starting your engine, then I think you have bigger problems..

RickB said:

Rubber, like many polymers, shrinks as it warms up.

That's why your loose fan belt stops squealing after it gets hot from slipping ... it shrinks and is too tight to slip.

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Guess I shouldn't have used "rubber" as a generic term. there are literally thousands of rubber "like" materials I actually don't know what it is only that over time it becomes extremely soft, almost jelly like. A condition that worsens with heat, then chokes the fuel until it cools and shrinks slightly.

jukesy said:

If the belts on your alternator is squealing from that kind of load just from starting your engine, then I think you have bigger problems..

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I think that's the point. At least with old V belt set ups that most of us have. I think I've posted it before- but the cycle goes like this: belt gets old, out of adjustment, and begins to slip slightly. This glazes belt and also begins to wear the flat areas of the V pulley on the alternator. Bubba adjusts the belt, but it still squeals at start up due the glaze and worn pulley. Bubba tightens it more, enough to overcome this problem. The rub is that he now has excessively loaded his alternator and water pump bearings. Soon either of these could fail, or as the belt wears more it starts squealing again. In this case, Bubba goes to Auto Zone, gets and installs a new belt. Everything is great for a week till the cycle starts over again. THE CURE is to replace the belt and the pulley together, then monitor tension to avoid slipping to begin with.

boatpoker said:

Guess I shouldn't have used "rubber" as a generic term. there are literally thousands of rubber "like" materials I actually don't know what it is only that over time it becomes extremely soft, almost jelly like. A condition that worsens with heat, then chokes the fuel until it cools and shrinks slightly.

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Most o-rings used in fuel systems and hydraulics are made from Buna-N, or a derivative of this. Normally there is minimal swelling/shrinkage unless the temperature range is exceeded (-40 to 250F) They have poor resistance to UV damage and weathering though.

Occasionally Neoprene is used, only good to 225F, but more weathering resistance. These are often used in cooling systems and A/C systems.

A better quality Oring material for fuel systems is Viton. Good to 400F and excellent chemical resistance. You may have to go to a specialist supplier for these though.

CaptTom said:

Anybody have part #'s or links to either mechanical or electric lift pumps for the Perkins 6.354? It sounds like a very good item to keep in spares!

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Here's some sources for you. The 1st is just informational giving places and part #s to look under. I didn't include a link but TADiesels.com is a US parts house as well and deals with lots of marine specific items-this pump is not marine specific. They have it for about $57. There are versions of this pump available as well without the manual primer lever-so be sure you check a picture before buying.

Perkins Fuel Pump G2641720


Perkins Fuel Pump Part #: 2641720 for Sale! | TruPar America


1446 951 M91 2641720 2641729 - Discounted all Tractor Parts Catalog

Forkliftt said:

... the reason your fan belt stops squealing after it warms up is that the alternator load has reduced after it replaces the voltage used from the battery when starting. Less load, stops slipping.

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That too ...

Gates Belts and Applications: Fiberglass vs. Aramid Tensile Members In Belts

I carry spares engine belts too-So that's ALL irrelevant to my original intent to let folks know that just because the manual lever still moves fuel doesn't mean the engine operated arm is working the diaphragm enough to pump fuel. So crack those lines between the lift pump and the engine filter or injection pump.

The lift pump can fail from a failed diaphragm. If that happens it is possible on some engines for fuel to get into the oil supply. It is worth checking your oil for fuel contamination.

The slipping alt belt , usually is far too weak to overload an alternator ball bearing.

What happens is the pulley gets really hot , the heat is passed down the shaft , the bearing LUBE leaks out and the bearing is toast.

Darylat8750 said:

The lift pump can fail from a failed diaphragm. If that happens it is possible on some engines for fuel to get into the oil supply. It is worth checking your oil for fuel contamination.

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Yes, in fact boating 101 suggests we check our oil daily when cruising. While you're at it do the same with the coolant and transmission oil. For oils, not only is it for level but also smell and color.

Sorry for the ABCs, but some sail boaters join us from time to time here on TF.

Turns out one of the one-way valves inside the pump had come out of its bore!!!! I ordered a new rebuild kit-naturally it didn't contain the parts for my pump. It did however have a valve and seal and the diaphragm that matched my pump and I peened the entire lip around the valve's bore. I wouldn't rebuild this one again since doing that but I now have a back-up again. It lasted 30 yrs, and I can't see me owning this boat for another 30. I should be fine on the lift pump (knock wood) for my ownership term. Now if I can just find a replacement injection pump for my Volvo MD5 and get my old genset back up and running!

Found these and have used them before on race cars with carbs. Which one would you use on twin Volvos TMAD60 C 250 hp? https://www.pegasusautoracing.com/g...&pmt=b&pdv=c&gclid=CJ2J0aH_trsCFUgS7AodKnIATQ

Those are all "gas" pumps. I've heard of numerous failures with folks using other gas designed pumps. There are numerous diesel pumps available aftermarket. Personally, if it would meet the demands of the engine I'd use one of the Carter lift pumps used on Dodge trucks after 98.5. These got a bad reputation for failing due to heat and vibration at about the 80-100K mark. Relocating them off the engine seemed to remedy this issue. There are more HD pumps available that weren't full-on HP pump/filter assemblies. This is the route I preemptively went with on my Dodge. Placing an appropriately scaled pressure gauge between these pumps and the engine give a continuous indication of the pump's health and they typically give lots of warning that they are weakening via reduced output pressure. I'm sure Volvo has recommendations as well and will be spec'd for your particular engine.