engine problems

[gonfishing]

i had an engineer /mechanic look at my boat at the weekend and after extensive investigations we discovered that the cam shaft that drives the fuel pump is worn and this has been causing my fuel problems ????????????? so i am going to fit an electric one, any ideas as to the best one to fit and/or where i can get one ??

julian

<hr width=100% size=1>WHAT??? more petrol!!!

 

[BarryH]

Now here lies the problem. What engine have you got, what does the existing pump flow, when its working, in ltrs/hrs. What pressure does it run at and has it got a fuel return pipe from the carbs/diesel injector pump.

If you is running petrols I would be a bit weary running a leccy pump. All the while the ignition is on its pumping, unless its got a pressure shut off switch built in. Then of course will your insurance make a fuss about changes to the fuel system.

If you is running a volvo, be it OHC or OHV, then I'd look at this cam shaft anyway as it will run the dizzy as well. Not a hard joband it can be done witht the engine in situ if you have enough room to wiggle it out. Getting another will be easy enough without breaking the bank. In saying that, are you sure its the cam and not the follower on the pump lever?. Never heard of the cam lobes going on one of those before, even on 200+ K milers in cars. If it has gone it will be due to oil starvation. So i'd look at the rest of the engine as well.

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[tr7v8]

Must agree with Barry H, I'd never run an ellecy pump on a boat, specially a petrol one.
However if you want to do it as a temporary fix then run it off a relay off of the oil pressure switch. Least that way if the engine stops the pump does ditto.
I reckon it's more likely to be the fuel pump than the cam. Are you sure the pump arm isn't worn or bent. Another thing is to check it hasn't got too thik a gasket block, that reduces the flow and can be a real pain to find.

<hr width=100% size=1>Jim

Draco 2500

 

[ArthurWood]

As others mention, more likely follower than cam. Have you checked sight tube to see if fuel in it? If so, pump diaphragm duff. Haven't followed your probs prevly, but have you checked carb?

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[BarryH]

Oh right just looked at your profile, should have done that first really. Okey dokey, B130's. So they be the old push rod ohv lumps. The petrol pump on those is the same fitment as the old volvo 140 series cars. To you, from my trade place 8 quid each. Your cam will run the dizzy, the petrol pump and the oil pump as well. Along with the pushrods of course.

If you take the pump out you should, if its the original, find that the follower/lever is actually a folded design, ie the lever is made from a flat bit of metal folded! Crappy design Pound to a penny that its the lever thats gone tits up and worn. The cam lobes are case hard'nd the pump lever shouldbe to,but to a lower standard. Is the plate and the gasket still there. The plate basically set the "gap" between follower and cam lobe. If its not there then the gap has been too tight and caused the wear. Thus putting a bit more pressure on the lever and lobe!

You should have solex side draught carbs or if a real early one maybe even stombergs. Niether of these has a petrol return to the pump like the down draughts. The petrol flow is stemmed by the float valves and relies on the pump overcoming it by just the valves not opening in the pump body due to the pressure build up or its got the little sprung loaded relief valve in the diaphram. Also the diaphram can become a bit brittle and hard after a long period of time.

I would say from what you have said that a replacemnet pump should cure your probs. Don't bother going to V***** for another one or a sevice kit it just ain't worth spending out there kind of money, if they still stock it that is. Volvo quoted me mega bucks for a new coil for my aq145, Lucas did it for 17 quid and it was listed in their catalouge as volvo marine aplications!

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[mtb]

Re:Never

I sell pumps and carbs and never in all my young years has a cam worn !! re the fuel pump lobe.

As the other lads have said it's more than likely the pump diaphragm or the none return valves . The pump should be a U type possibly 461-212 or 7971371 .
Some times people forget to make sure the cam is at it's lowest point before pumping the priming lever, then tell them selves the pump is shot.
I know you must have checked the fuel lines are clear and the gauze in the pump is clear allowing fuel to flow to the pump, so the only thing left to say is the pump outlet pressure is not normaly more than 2.5lb to 3.5lb .
Oh when you checked the pump you did make sure the cap on top was located ok as an air leak will stop every thing
Cheers
Mick

<hr width=100% size=1>One day son all this will be yours #### off I dont want it

 

[ccscott49]

Just to add my tuppence worth, I've never seen a cam lobe for a fuel pump wear, in 38 years of working on engines. Pump actuating levers, yes.

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