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Thu Apr 05, 2012 7:41 pm

So I've read multiple threads with multiple opinions and I'm looking for a definitive answer. Heh.

Anyway, for simplicity's sake, I've ordered a nice Pierburg electric fuel pump from the good folks at German Supply, complete with proper German relay. I've not found any negative comments on this pump anywhere. At any rate, I'm going electric. It's a done deal.

My question is, when I switch over, with a fuel pump block-off in place, should I leave in the pump push-rod?

I have seen many posts from quit knowledgable people who say that the pushrod should be left in because it gets lubrication from the primary oiling system and taking it out will cause a loss of pressure. I've also seen posts that say that this is incorrect.

So, whenI remove the existing pump (pressed together Mexican thingy) should I also take out the pushrod?

If I leave the pushrod in, ostensibly to avoid a loss in oil pressure at an important location, won't I end up with a pushrod going thwacka-thwacka-thwacka against the blockoff?

Insights, the oilier the better, are appreciated.

This is for a dual port 1600 in a '58 Type 1, not that that has much bearing, but someone will ask.

Thu Apr 05, 2012 8:02 pm

I dont know about other's opinions here but I have used an electric pump for many years and install the blockoff and never had the pushrod in. Never had an issue with oil psi or anything. My opinion is remove it.

Thu Apr 05, 2012 8:15 pm

Did you order the blockoff plate from John when you ordered
your New pump?

The fuel pump pushrod gets oiled from Splashed oil.

take the pump,and the rod&guide out and put it in a sealed
bag to store it.

More importantly is ...Where are you mounting the new pump?

Thu Apr 05, 2012 8:34 pm

So two responses, two opinions. :D

DKP, I'm going (up front) fuel tank, short line, filter, pump, pressure gauge, main line, filter, (at the back)hard line into engine compartment, connection to carb.

Part of the appeal of this set up for me is keeping the engine compartment as clean and simple as possible in terms of connections. Every connection is a possible break and a possible inferno, as far as I'm concerned.

I've got a fused relay coming with the pump to shut it off if the engine dies, and just for paranoia, I'm going to scrounge up an inertia switch. I've also got diagrams to wire up a kill switch (why not?) and a straight-in push button for filling the bowl when it hasn't been run for a while.

The Pierburg electric seems to offer the best flexibility, stable pressure, and safety. I was originally going to try to stay mechanical, but Concept-1 dicked me around when I tried to order what appeared to be one of the only passable currently produced mechanical pumps still on the market, so I sensibly went with the Pierburg electric from German Supply like I should have done in the first place.

So, just to emphasize my ignorance, what is a "sealed bag" and where would a simple fellow like myself go about acquiring such an appliance?

Thu Apr 05, 2012 8:43 pm

Quote: take the pump,and the rod&guide out and put it in a sealed
bag to store it. Just in case your kidding he's telling you to put your old parts in like a ziplock bag for storage.

Thu Apr 05, 2012 9:08 pm

To be fair, I wasn't entirely sure. :D

I keep a supply of spares under the hood that includes everything from oil to my old 009 with Pertronix (since replaced with a beautifully restored 019 from Glenn). I can quite easily add in a couple of pieces of hose an the old Brazilian fuel pump just in case.

So, to err on the side of paranoia, and just for emphasis, there are no worries about just taking out the rod and putting on the block off?

It's always good to ask, just in case. :D

Thu Apr 05, 2012 9:24 pm

Well you could ask to have this post moved to the preformance-engine/transmission section and get a whole different set of opinions not that this is in the wrong section it's right for your year of car there are just more of the engine building/modifying crowd in there or a another bucket of opinions. You could just ask the place you bought your new pump from what there opinion is. I like the removing it all and keeping it in a bag under the hood plan.

Fri Apr 06, 2012 8:12 am

Maybe I don't understand the problem. I have an electric fuel pump and a blockoff plate. Taking the stock pump out requires taking the bakelite spacer out too? The rod will move up and down roughly 5mm as the crankshaft spins. And jam itself into the plate so the rod has to come out. I don't used the electric pump anymore. I don't mind having it as a spare but don't see why it's better than the stock pump. Plus the electric requires a separate regulator to keep the psi down to 3-3.5, something handled easily with the stock pump. What's the benefit???????

crvc

Fri Apr 06, 2012 8:15 am

58Blue wrote: So two responses, two opinions. :D

Unless I'm reading something wrong I believe both your responses were the same. The rod comes out.

But just to make sure, how would you install the block off plate if you left the rod in?

Fri Apr 06, 2012 9:22 am

drscope wrote: But just to make sure, how would you install the block off plate if you left the rod in?
If you did, it would either bend the pushrod, damage the distributor drive or punch a hole on the blockoff plate.

The rod MUST come out.

Fri Apr 06, 2012 9:44 am

It's been several years and I've forgotten how I set up the electric fuel pump. Does the bakelite spacer need to come out too? Is it left in place and the plate bolted atop it? What's the chance the spacer will come out without leaving the bottom half still in? In my bug it's stuck down there and I can't get it out. That may be why I took the electric pump out and went back to the stock pump. Plus the pump was noisy and it was a pain trying to set the regulator psi.

crvc

Fri Apr 06, 2012 10:04 am

You can leave it in if you think it will break.

Fri Apr 06, 2012 10:22 am

drscope wrote: 58Blue wrote: So two responses, two opinions. :D

Unless I'm reading something wrong I believe both your responses were the same. The rod comes out.

But just to make sure, how would you install the block off plate if you left the rod in?

Yeah, I read it wrong. It was late. I was tired. There may have been alcohol involved. :oops:

There seem to be a lot of people running without the pushrod with no problems at all, and yet there are threads that suggest the push rod is important to maintain oil pressure due to its proximity to an oil gallery and that if you're using a block off plate, you ought to use a cut down push rod.

On further reading, I'm finding that this may be an issue with Type IV engines, but almost definitely isn't with the Type I. The idea has spread, though, and comes up often enough that I thought I should ask.

My current belief is that it isn't needed, but I could be wrong. That happens.

At this point, I haven't even got around to ordering a block off plate. German Supply didn't have any listed when I ordered the other stuff so I'll have to order it from somewhere else. As I've now expanded my plans to include an overall fuel system rejuvenation from the tank back, I'll likely be ordering other stuff, so I figured I'd wait and get it all at once.

Fri Apr 06, 2012 5:02 pm

58Blue wrote: for simplicity's sake, I've ordered a nice Pierburg electric fuel pump

This isn't having a go at you, it's just a general statement as I see that said all the time and really don't get it as adding an electric pump is the complete opposite of simplifying things.

A stock mechanical pump just bolt on and drive, you can even keep a spare one in the front in case there's a failure.
At worst you may have to add a couple of gaskets to bring the pressure down.

Electric ones require mounting somewhere, on special rubber mounts cos they are noisy little feckers.
An electrical system to run them and a cut out device for safety.
And because they don't vary the pressure with revs like the stock mechanical one alot of them also need a regulator.
I've also seen many which don't stop the flow when turned off so park facing uphill you may get a sump full of gas, so it's a good idea to add an inline electrical solenoid.

A stock mechanical pump will keep an IDA fed 2L + engine happy and has worked well for millions of VWs across the globe for many decades.

To answer your question though, there is absolutely no reason to leave the rod in, it's just riding on a spiral on the dist drive shaft so it;s not hurting anything not being there, infact its wearing things less.

Fri Apr 06, 2012 6:03 pm

Joel wrote: 58Blue wrote: for simplicity's sake, I've ordered a nice Pierburg electric fuel pump

This isn't having a go at you, it's just a general statement as I see that said all the time and really don't get it as adding an electric pump is the complete opposite of simplifying things.

I see what you're saying, and I suppose "simplicity" may not have been the best way to put it.

It's simpler and cleaner in the engine compartment, where all you've got is one line coming to the carb, with no fuel line running over top of the distributor. Fewer hoses and fewer connections appeals to me, with my paranoia of engine fires.

The pump and the wiring are up front. I'll put a filter before the pump, then one at the back where the line comes out. I've got an inline pressure gauge I'm going to put up front, just to be sure of the pressure, but the Pierburg is internally regulated to 3.5 psi.

As far as noise, the oscillating type have an awful buzx, but the rotaries like the Pierburg and the Carter are reportedly very quiet. I guess I'll find out when I get it set up. It'll have to be pretty loud to hear it over the engine, though.

Part of the decision is driven by the difficulty in finding a decent quality mechanical pump these days. There's nothing out there but the $20 pressed together ones, and I've come across a fair number of accounts of the membrane in those tearing and dumping fuel into the case. Again, maybe I'm just being paranoid.

The electric also gives you the option of a kill switch, which may provide some small measure of theft protection. You can also wire in a push button to run the pump for a few seconds to fill the carb bowl if the car hasn't been run for awhile. The possibility of vapour lock on hot days is also a lot lower, provided you keep the fuel line properly routed.

Having said all that, philosophically, I'd have preferred to stick with a good quality German mechanical pump, but it seems everything out there, including the rebuild kits, are of suspect quality.

Fri Apr 06, 2012 6:22 pm

I would be interested in hearing if your Pierburg is quiet since my cheapo pump does make a lot of noise. But it does tell me that the pump is running as soon as I turn the key and to hurry up and start the car. That leads me to a question: why do you need a separate "button" to prime the carb; isn't the key enough?

Fri Apr 06, 2012 6:26 pm

I know where you're coming from re. quality of replacement pumps.
Although the only diaphragm failures Ive seen have been from people putting the filter after the pump and trash from the tank gets pounded into it.

The main failure is the pivot pin falling out as they are too cheap these days to fit circlips.
There are ways around that though.

I try and advise against using kill switches on the pump power.
Reason being the car will still start and run for a couple of mins before the fuel bowl empties.
This usually just long enough that a would be car thief gets out onto the road before it cuts out, then bail out leaving the car sitting in the middle of the road.
Or you do that to yourself forgetting to turn it back on.
A Kill switch on the ignition is much better option.

Definately put a filter before the pump though, that is the biggest killer of electric pumps, they don't handle crap from a 40+ year old fuel tank going through them real well.

Fri Apr 06, 2012 6:30 pm

schunacher wrote: I would be interested in hearing if your Pierburg is quiet since my cheapo pump does make a lot of noise. But it does tell me that the pump is running as soon as I turn the key and to hurry up and start the car. That leads me to a question: why do you need a separate "button" to prime the carb; isn't the key enough?

You really shouldn't have the fuel pump wired to run when the engine isn't started.

There are many ways to do that, using the charge system to power a relay means the fuel pump only runs while the gen is charging.

Or better yet is an EFI tachometic relay, it works of the tach signal from the coil.
The GM one I used also had a prime feature too.
It ran the pump for 2 secs on ignition then waited till the engine started before running again.

One of those is necessary so in the event of a crash the pump stops running so you don't burn yourself alive :wink:

Fri Apr 06, 2012 6:40 pm

58Blue wrote: Joel wrote: 58Blue wrote: for simplicity's sake, I've ordered a nice Pierburg electric fuel pump

This isn't having a go at you, it's just a general statement as I see that said all the time and really don't get it as adding an electric pump is the complete opposite of simplifying things.

It's simpler and cleaner in the engine compartment, where all you've got is one line coming to the carb, with no fuel line running over top of the distributor.

Im not sure how you think fuel is going to get to your carb but is still has the same route over the distributor to get to the carb (assuming you have a single carb) also millions of people have run the stock set up with no problems. The ones that have the problems are the ones that run shitty fuel lines, fuel filters in the engine bay, they pull the fuel line off the carb causing the brass fitting to become loose and it eventually pops out of the carb with the fuel line attatched to it, etc. I run hose clamps on all my lines andI check my hoses regularly. Point being you have the exact same problems with connection (minus one with no fuel pump) in the engine bay and now you have the added problems of all the electrical crap you've added and an electric fuel pump that will most likely crap out. You want a good mechanical pump? Get an original pump and rebuild it. If I were you I'd keep the mechanical setup.........at least cary all your mechanic pump parts with you for the day you need them.

Fri Apr 06, 2012 6:43 pm

My tank's not in too bad of shape for being over 50 years old, but I've got a full POR-15 kit for cleaning it out and coating it on the inside. I'm also going to blow out the main line really well and replace all the soft lines.

What you're saying about the reason for diaphragm tears makes sense. I hadn't thought of that. And anything large enough to tear the diaphragm would sure do a number on an electric pump.

Well, the electric is on its way, so I'll try it out and see how it goes. It's motivated me to do a full refurb of the fuel system, so it's a good thing on the whole, even if I eventually decide to simplify in the other direction.

I'm going to keep looking for a good mechanical pump. Even if I don't end up installing it, I'll know I have a reliable backup. There is a guy somewhere on here who does very nice pump restorations, but I lost the bookmark for his site. If anybody knows who it is, please let me know.

Schunacher, the button is a way to run the pump before the engine starts. I could be misunderstanding things, but I believe the fuel pump relay (which I ordered on multiple recommendations) works by using pulses from the coil to determine if the engine is running. It would therefore work during cranking and while the engine is running, but not just when the igniition is turned on. The relay is there to prevent the pump from continuing to run in case you have an accident and the engine dies, as it would if you directly wired the pump to the ignition.