Petrol pump confusion.

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Velgreeno

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Hey folks. Once again I'm in a bit of a confused state. I know ha. What it is. I have never touched the petrol pump on my engine in over 20 years and want to get a back up should it fail and my knowing my luck that will happen and that's the only spare I haven't got really. Question is. My engine used to have a dyno with dyno petrol pump but I upgraded to alternator a few years ago but never changed the petrol pump. All works good right now (touch wood) but for a back up do I get an alternator pump to comply with it or just get another dyno petrol pump as it works. This is my current pump
 
I don’t think that’s the original pump but it might be worth doing a rough pressure test on it to see how well it’s doing. Then you’ll know if to carry a spare or not. The older the pump, the better it is it would seem and that looks old but not the original. I’ve had a modern replacement last less than a week, and I’ve had its replacement last four plus years. To do a check on the old one, pop the fuel pipe off from the carb and shove it in an empty 1.5 - 2L water bottle on its side , slide it in about an inch or so and get your assistant to crank the engine and count to three then stop. The fuel coming out of the pipe should hit the bottom of the bottle with a little gusto in top condition and on the other hand just a limp drip just inside the neck if it’s almost buggered. Disable your engine from starting first, and don’t set yourself on fire by doing it on a hot engine. There’s lot that can go wrong here so be careful and hold the bottle and the pipe and mind the fan belt. The other issue is, can you get it off easily as it’s fitted on a block / guide that’s easy to break and the other thing to check is that the pushrod is still long enough as that wears down too. Will it clear the dynamo for removal ???. When you have it apart, it may be worth checking your fuel, pipes and clips , if they’re old, they may not take kindly to being removed and shoved back on again. That jubilee clip looks a bit tooooo big, might have got away with it so far but might not once the pipe is removed and replaced.
Do the pressure test then have a ponder once you know.

Ozziedog,,,,,,, it’s never straight forward is it. :)
 
I don’t think that’s the original pump but it might be worth doing a rough pressure test on it to see how well it’s doing. Then you’ll know if to carry a spare or not. The older the pump, the better it is it would seem and that looks old but not the original. I’ve had a modern replacement last less than a week, and I’ve had its replacement last four plus years. To do a check on the old one, pop the fuel pipe off from the carb and shove it in an empty 1.5 - 2L water bottle on its side , slide it in about an inch or so and get your assistant to crank the engine and count to three then stop. The fuel coming out of the pipe should hit the bottom of the bottle with a little gusto in top condition and on the other hand just a limp drip just inside the neck if it’s almost buggered. Disable your engine from starting first, and don’t set yourself on fire by doing it on a hot engine. There’s lot that can go wrong here so be careful and hold the bottle and the pipe and mind the fan belt. The other issue is, can you get it off easily as it’s fitted on a block / guide that’s easy to break and the other thing to check is that the pushrod is still long enough as that wears down too. Will it clear the dynamo for removal ???. When you have it apart, it may be worth checking your fuel, pipes and clips , if they’re old, they may not take kindly to being removed and shoved back on again. That jubilee clip looks a bit tooooo big, might have got away with it so far but might not once the pipe is removed and replaced.
Do the pressure test then have a ponder once you know.

Ozziedog,,,,,,, it’s never straight forward is it. :)
Hey Ozzie. Cheers for the reply. Oh right. Its been on there long time though. Its the only part i haven't replaced or upgraded ha. Right now everything is fine and working as its supposed to with right pressures etc and it seems ok condition wise too. Its not made me go ooh not good yet. . Im looking at Alan Schofields pumps as i have never had any probs with them and everything i have bought from them has always been great. On their fuel pumps they say they are great quality too. If i did get the spare just in case because me being me its just peace of mind that i have one ready to go on if i needed it. Im thinking maybe a dyno will be ok to get as a spare even though she has been converted to altenator because the existing one is dyno i believe and i have had no probs so far but altenator pump. Hmm dont know. As for the jubilee clip ohh its on tight and that hose is staying put. I never have anything that's ill fitted or loose on my bus ha and the fuel line are just over a year old and they are cohline and all good as far as i can see 🤙.
 
Hey folks. Wel i finally cracked it. Indeed i do need an altenator pump and i got one and the one i got is for an altenator conversion too so its all good. Apparently the dyno pump shouldn't really work on an altenator but well there we go ha. 😊🤙
 
Hey folks. Wel i finally cracked it. Indeed i do need an altenator pump and i got one and the one i got is for an altenator conversion too so its all good. Apparently the dyno pump shouldn't really work on an altenator but well there we go ha. 😊🤙
Hope you got a new pushrod as well as they are different lengths
 
Hey folks. Wel i finally cracked it. Indeed i do need an altenator pump and i got one and the one i got is for an altenator conversion too so its all good. Apparently the dyno pump shouldn't really work on an altenator but well there we go ha. 😊🤙

When I did an alternator conversion on my 1973 VW 1600 Type 2 back in 1988/89, I used the original upright dynamo-type fuel pump, but I reduced the phenolic spacer (with integral guide-tube) thickness by 6•0 mm and shortened the push-rod by 6•0 mm; giving sufficient clearance between the alternator body and the fuel pump. I am open to offers for these; having upgraded to a Type 4 engine.
 
Having replaced the dynamo with alternator on my Karmann Ghia with 34pict 3 carburetor I have followed this item. Firstly I think you are going to have problems removing the dynamo type fuel pump.You might be able to remove by taking off carburetor but is going to be very tight and you might have to some how lift alternator to allow you to remove pump ie lift fan housing. Looking at photo there seems to be a mark where accelerator pump linkage is rubbing against side of alternator, to solve this problem you should have fitted a spacer between intake manifold and carburetor so accelerator linkage is clear of alternator . Later engines fitted with alternator had a taller intake manifold flange to solve this problem. When you change to later type alternator fuel pump you will also have to change fuel pump push rod for shorter one. When you get alternator type fuel pump you will notice the different shape that keeps it further away from alternator housing. Both spacer and shorter push rods are available from regular suppliers. Finally it was mentioned that dynamo fuel pump should not work with alternator. A fuel pump is a fuel pump and the only difference is the shape of later pump to clear alternator and make it easier to remove.
 
Having replaced the dynamo with alternator on my Karmann Ghia with 34pict 3 carburetor I have followed this item. Firstly I think you are going to have problems removing the dynamo type fuel pump.You might be able to remove by taking off carburetor but is going to be very tight and you might have to some how lift alternator to allow you to remove pump ie lift fan housing. Looking at photo there seems to be a mark where accelerator pump linkage is rubbing against side of alternator, to solve this problem you should have fitted a spacer between intake manifold and carburetor so accelerator linkage is clear of alternator . Later engines fitted with alternator had a taller intake manifold flange to solve this problem. When you change to later type alternator fuel pump you will also have to change fuel pump push rod for shorter one. When you get alternator type fuel pump you will notice the different shape that keeps it further away from alternator housing. Both spacer and shorter push rods are available from regular suppliers. Finally it was mentioned that dynamo fuel pump should not work with alternator. A fuel pump is a fuel pump and the only difference is the shape of later pump to clear alternator and make it easier to remove.

When I did my alternator conversion, I had no problem fitting & removing the upright, dynamo-style fuel pump with the alternator installed. However, I did need to modify the throttle linkage to the Minnow Fish carburettor, to clear the alternator body.
 

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