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The 1500 mechanical fuel pump

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bigjones

bigjones

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The more I look at electric pumps the more I want to go back to the mechanical. Problem is that I disembled the suspect mechanical one and it looks brand new - diaphragm looks just fine. I never took this one apart before but I noticed one of the lock washers was broke in half. I wonder if this could possibly have led to air getting in - the top not fastened down tight enough. Can't see it myself but it's niggling.

Anyways, I was looking at the Moss catalog and noticed later 1500's had a distance piece (a pump with a longer arm was used).
I'm wondering if this was as a result of reports of vapour lock in earlier 1500's. I'm thinking of ordering the later pump and distance piece - anyone got any comments?

Another idea - how about a heat shield for the pump - or is that just crazy?

Cheers
 
There seem to be two different mechanical pumps - both for the 1500's one has a different angle of entry than the other and for some reason I don't think they are interchangeable.

I don't see the point of a heat shield for the fuel pump. If it is pumping, the fuel is flowing and therefore you don't need to worry about vapour lock. I know I am risking wrath when I say this, but, the longer I am on these boards, the greater my sense that most of the time what is diagnosed as vapour lock isn't. Listening to descriptions, it sounds like air issues or fuel flow issues but not vapour lock. I also suspect this because if vapour lock were that huge an issue someone would have beaten our little cars into tinfoil with a bat sometime in the last 30-40 years out of sheer frustration.
 
I don't think the distance piece is avalible. You can take yours apart? Mine is crimped. How's the spring look, is it weak? That's what does the actual pumping.

What carb do you have? Got a pic of your fuel line routing?
 
JP,
Yeah, that's what I'm on about. According to the Moss catalog, the later 1500's came with a spacer block -5/8" thick. Obviously this then needed an pump with a longer arm and angle. Did BL know about vapour lock problems and so introduce the spacer (to shield the pump from engine heat) and therefore they needed to have a longer arm pump. Or, did the first pump become NLA and they had to use the second longer arm pump and then they needed to put in a spacer.

Hate to say this but the first year of this model (1975) had big problems:
Rod bearings
Cracked exhaust manifolds
Bad engine mounts
I've come close to taking the bat to it!

The reason for asking is if the first scenario is true then I'll get the spacer and 2nd pump. My car broke down last week - there was no fuel getting the carb when I cranked the engine (I disconnected the gas line just before it entered the carb and no gas flowed). I therefore need to get another pump but I would like to get the best. I don't fancy an electric one because I would have to cut the gas lines at the back - I was hoping to put one in the engine bay but that appears to be a big no-no. The Mr. Gasket pump I just got from Advance Auto even says says don't it in capitals.

Kellysguy,
I'm not sure where I got this pump from - I'm thinking Advance Auto - their site shows they have a Beck/Arnley - not sure if that is what I got or not (spring feels good):
Internals.jpg


Lid.jpg


I've recently put in a HS4 - it was running just fine for about a week. Here's pic of the routing:
FloatBowlLid.jpg

The Moss catalog shows the distance piece is available but maybe they've not updated it.
 
so, I replaced the engine mounts and the thrust bearing and mine is running rock solid - manifold is fine though I have a spare and will likely go with a header when the time comes. Before you do anything, reassemble the pump and see if it actually pumps. You should be able to produce decent suction just by pumping it off the car. Those pumps are pretty reliable and your blockage may have been elsewhere - like a sludgy tank.
 
Your routing is similar with mine. I had problems w/ heat from the heater hoses where the line comes up from the tunnel. Put a bit of split line over it there. I have an electric pump on mine up front right where your inline filter is. Works o.k and no need to cut the steel. I don't know if SU's will take a full 5-6psi, so others need to chime in. O'Reilly's supposedly has a 2-3 psi pump. I bought one and it put out 6. Pro's and cons to electric. I can prime quick if I run out, pull fuel off for the lawnmower if I'm lazy and can empty tank of stale fuel. My car doesn't sit long enough for fuel to go bad though. NOt the best case scenario, but it will work up front. P.O put it there.
 
Look to NAPA and A.C. pumps. If you find a sympathetic counter guy there are PICTURES in CATALOGS.
 
Before we go any further, yes or no, does the mechanical pump work? It's a real easy check, and, if the pump works, then the problem isn't going to be solved by an electric pump.
 
Tweety,
Wow, its an old trick? There's me thinking I'm a genius.

Kellysguy,
Thanks for the tip - I'll wrap the line with that insulation pipe stuff.

Doc,
You have the Carter pump. Can you recall if the "instructions" said not to use in engine bay?

JP,
Sorry if I came across as argumentative. The pumps seems to work fine off the car - pumps water with no problem and the internals look OK. I was thinking it might be some sort of intermittent problem with the pump.
Anyway, here is the plan:
I hooked up the Mr. Gasket pump in the engine bay - the car runs fine.
MrGasket.jpg

I'll disconnect at the carb and point it into a fuel can. Run the Mr. Gasket until the tank is empty and see what happens. Sound good?

Cheers
 
:lol: Ha! You can get 2 from just one paint tray.

OK, here's the plan - someone please tell me if this is a bad idea:

I used Mr. Gasket to pump the tank dry. No sediment, just a couple of specks in the glass filter. Fuel gauge was reading 1/16 full. When I broke down the gauge was reading something like 1/4 full. However, I'm prepared to accept that the car ran out of gas. When I got back with a gallon the poxy starter motor had STB. Cannot think why it didn't fire up when the 2 guys pushed-started, but hey, moving on.

BUT.....this is the plan:
I'm going to re-install the mechanical pump and run the line through Mr. Gasket. I'll hook up Mr. Gasket electrically through a switch that will be in the cockpit. If I get the "vapour lock" symptoms, I'll flip the switch to activate Mr. Gasket and see what happens. A cube Facet will be in the trunk in a box, all pre-wired, as a back-up to Mr. Gasket. If the mechanical pump fails, I'll pull over to a safe place and just disconnect the fuel lines to it and get home on Mr. Gasket.

Cheers
 
Piece Of Something.

And as of two weeks ago, that's the same POS pump that is on my Mini.
 
bigjones said:
JP,
Sorry if I came across as argumentative.
Click to expand...

Sorry if I did also. Trust me, you absolutely did not come across as argumentative. Quite the contrary. The reason I was being insistent (Ok Strident :wall: ) was that it is easy to change a number of variables at once. This doesn't work well, don't ask me how I know. Was just encouraging one thing at a time. Sounds like you have a plan with the electric backup. Let us know how it goes.

Cheers! :cheers:
 
JPSmit said:
bigjones said:
JP,
Sorry if I came across as argumentative.
Click to expand...

Sorry if I did also. Trust me, you absolutely did not come across as argumentative. Quite the contrary. The reason I was being insistent (Ok Strident :wall: ) was that it is easy to change a number of variables at once. This doesn't work well, don't ask me how I know. Was just encouraging one thing at a time. Sounds like you have a plan with the electric backup. Let us know how it goes.

Cheers! :cheers:
Click to expand...

WHAT.....ARGUEMENTATIVE ?!?!?!?

WHO YOU CALLIN' ARGUMENTATIVE ??!?!?!?!?!?!?

YOU'RE WRONG.....THE BOTH OF YA !!!!!!!!!!! :jester: :jester: :jester:
 
kellysguy said:
JPSmit said:
bigjones said:
JP,
Sorry if I came across as argumentative.
Click to expand...

Sorry if I did also. Trust me, you absolutely did not come across as argumentative. Quite the contrary. The reason I was being insistent (Ok Strident :wall: ) was that it is easy to change a number of variables at once. This doesn't work well, don't ask me how I know. Was just encouraging one thing at a time. Sounds like you have a plan with the electric backup. Let us know how it goes.

Cheers! :cheers:
Click to expand...

WHAT.....ARGUEMENTATIVE ?!?!?!?

WHO YOU CALLIN' ARGUMENTATIVE ??!?!?!?!?!?!?

YOU'RE WRONG.....THE BOTH OF YA !!!!!!!!!!! :jester: :jester: :jester:
Click to expand...

Sheesh, here he comes again, who let that kid in the playground? :rolleyes: :jester:
 
Well, I'm pleased.

I've wired up Mr. Gasket to the old Hazard Switch on the radio console. The hazards never worked since I've had the car anyway. Actually used the Hazard Switch from my 1275 - that has regular electrical connectors. The 1500 switch has pins - sort of difficult making a connection to pins. Also had to reconnect the 1500 switch and let it hang loose because otherwise the turn signals won't work, ha!
Put the mechanical pump back and routed the gas line through the mechanical and then through Mr. Gasket. Mr. Gasket is there purely for emergencies.

Went for a test drive and all is well. BTW, the pump does not do the tap, tap thing - it's more like a constant whirring noise that I can't hear above the engine noise.

The cool thing is that every morning I can turn Mr. Gasket on to see if it still works and to fill up the fuel bowl before cranking the engine. Ar, ar.

Forgot to mention that when using Mr. Gasket to empty the fuel tank into gas cans, I used the cut-off switch on the battery to turn the pump off and on, ha!
 
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