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Feed Pump Question
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Gregory
1/3/2007 12:42 PM
Hi,

Ok here's the deal; I found a feed pump(second version) for my 70' 6.3, at one of my local junkyards the other day, and it works! or it turns rather, when current is applied. How should I go about getting it up to snuff? Just running fuel through it? Should I take it apart and clean it, or could that potentially do more harm than good? I don't know the state of the feed pump on my 6.3 because it isn't exactly in my possesion yet, so I thought it would be good to have a pump at the ready just in case. I also picked up a fuel pump for a 70' 300SEL 3.5, can I use parts from that pump if nessecary? By the way, the feed pump came off of a six cylinder 108. What are your thoughts?

Greg
Chris Johnson
1/3/2007 12:58 PM
Hi Greg,

First, forget the pump form the 3.5. It is a different style, and I strongly encourage you to keep the car is original as possible.

While there are things you can do to your spare pump, I would suggest doing NOTHING to it unless you determine that there is a problem.

These pumps should be tested for flow, and if the flow is correct, then leave it as it is. The "long body" pumps are easier to service than the "short body" pump, but the short body pump is certainly serviceable.

Be aware that the short body pump has a screen filter on the inlet fitting (the long body pump does not). This screen is the smallest filter in the entire system, and is the first to plug with tank sediment. You can tell when this filter is plugging up because the car will drive for a short distance and then sputter out. Wait for a few minutes, start the engine, and the car will go again for a short distance and then sputter out again.

So, check that screen! If it repeatedly clogs up, then you KNOW you have to have the tank cleaned!

With the pump powered up, it should pump AT LEAST a litre (about a quart) in 15 seconds. If not, then either the pump, the tank, the tank screen, the pump inlet screen, or the hose from the tank to the pump has a problem. Pump voltage should be at least 11 volts for the test.

Chris Johnson
"If you aren't constantly IMPRESSED with your car, then it needs fixing."
100.012-12-000790
109.018-12-000019
109.018-12-003834
www.300SE.org
Gregory
1/3/2007 1:12 PM
Dang, that is a pretty fine screen! There is some sediment on it, so would I be safe in unscrewing the intake port and cleaning it?

Greg
Chris Johnson
1/3/2007 1:29 PM
Yes. In fact, when you reinstall it, get it tight, but don't get is so tight that you can't unscrew it again while "on the road".

I usually keep a 3/8" socket extension bar (to plug the feed hose), a screw driver and a wrench in the car so that I can clean the screen if it clogs while driving the car until such time as I know that it isn't going to be a problem.

Chris Johnson
"If you aren't constantly IMPRESSED with your car, then it needs fixing."
100.012-12-000790
109.018-12-000019
109.018-12-003834
www.300SE.org
james lawson
1/3/2007 4:29 PM
Also, this pump needs to be primed to pump. It is such an easy job to take out the fuel tank you might want to do it it on principle.

jim
Chris Johnson
1/3/2007 5:06 PM
This is a common myth (no offense Jim). IF (and that's a big if) everything is okay, these pumps are self-priming.

If the pump won't prime itself, it is indicative of flow problems in the system. This subject comes up on a regular basis on this board, with common complaints relating to vapor lock issues.

IF everything is okay in the fuel system, then, not only will the pump create enough suction head to prime itself, but there will also be NO possibility of vapor lock while the fuel pump is running.

If the engine demonstrates symptoms of vapor lock after a "hot stop" when trying to start the engine, the vapor will be quickly eliminated by letting the fuel pump run for a few seconds before retrying an engine start.

I can see how this thinking comes to be. Virtually every car I have bought over the last several years has had problems with fuel flow through the system. However, I am quite satisfied that the factory engineers did a good job of designing the system so that these sorts of problems did not exist with a clean, unobstructed fuel system. If the system performs as it originally did, you can expect the exact same level of performance.

Chris Johnson
"If you aren't constantly IMPRESSED with your car, then it needs fixing."
100.012-12-000790
109.018-12-000019
109.018-12-003834
www.300SE.org
james lawson
1/3/2007 9:56 PM
Chris I probably should have said it differently. I don't think it will work if you just put a can of fuel on the ground and try to have it suck it up. I think that there is a reference in the manual that to check the flow there should be a certain amount of fuel in the tank as well. It is an impeller sort and not a vacuum type pump, so even if it is self priming it still is primed.

jim
Chris Johnson
1/3/2007 11:01 PM
I would agree that putting a can of gas on the ground might be asking a bit much, but if the pump is being feed from the tank on the car, it will suck the fuel into the pump without being primed if nothing is blocked.

Chris Johnson
"If you aren't constantly IMPRESSED with your car, then it needs fixing."
100.012-12-000790
109.018-12-000019
109.018-12-003834
www.300SE.org
james lawson
1/4/2007 12:12 AM
I thought it important to point this out since it is a spare pump and he might be testing it off the car and so would not assume it needs repair

jim
Gregory
1/4/2007 12:53 AM
The original fuel pump is still on the car. I want to test this spare pump just standing alone. Like I said before, when current is applied, the motor does turn, but past that, I don't know. I am going to remove the intake port and clean the filter; then test its pumping ablitiy. I was just going to fit a fuel hose up to it and let it try to suck up some fuel in a jar or something. What is the proper way to test the unit? And by prime it, do you mean, fill the pump up with fuel first, then turn it on?
Art Love
1/4/2007 3:05 AM
Have your can of fuel above the base of the pump like basically it is in the car so it gravity feeds. The pump runs on 12V, be VERY careful of sparks and fuel vapour.
Art
cth350
1/4/2007 10:01 AM
One means of safely testing the pump is to use kerosene rather than gasoline. It's less flammible and also lubricates better along the way. To some (like my wife), it stinks less.

-CTH
Gregory
1/4/2007 2:56 PM
Ok, here's the update. The pump moves fuel really well, however, it does leak around the negative terminal when the pump is activated and when there is a lot of fuel pressure just from gravity with the pump off. I unscrewed the terminals and discovered that there are o-rings on each connection; I'm guessing that I need to get new ones. Are they available?

Greg
Art Love
1/4/2007 7:48 PM
I wrote a response but then noted you had the short pump, not the long, so I have deleted it.
Art
mdavie02
1/12/2007 12:49 AM
If it's leaking at all, it needs a rebuild.
You can use the pump off the 108's, but get the bracket as well from the wreck so that the pump bolts right on. Yes, it is not original, but if you use the high pressure version from the 3.5, there will be no vapour lock problems. Fuel flow is quite adequate, as discussed extensively in the past. Replacement is then very simple. You can keep the original on a shelf if you wish.


Here is a list I was recently quoted for rebuld of a long pump. I have no experience with the short.

for the pump 0.442.200.007
parts required are
2*brushes $15.00+gst each **
2*springs for brushes $11.95+gst each **
2*orings $39.00+gst each **
1*oring $33.00+gst **
1*valve ( external fitting) 93.00+gst //
There are some other o-rings which we should be able to get, but these are
the main ones

Regards

Michael Davies
Gregory
1/12/2007 4:18 AM
Thanks for the information and pricing. Quick question though...The first time I put 12V across the 3.5's fuel pump, could feel and hear it start to move. The next time I tried it, not thing happend. Does this mean I killed the pump, or is it just gummed up and needs to be cleaned?
Gregory
1/12/2007 4:28 PM
nevermind, the 3.5 pump works.
Ron B
1/13/2007 6:23 AM
If you want to fit the 3.5 pump.be aware that the neg and positve terminal must be wired up correctly or it won't pump.It will run but won't work.
Try and use the entire pump assembly including the noise damper and filter because it features a fuel return systym which prevents vapour lock bubbles .

The bracket in it's entirety is also useful but will need some sort of bracket to drop it down so the fuel feeds in from above,same as the stock 6.3 pump.You can use the W116 or W126 pump which has identical bracket arrangement but they have a fuel pressure accumulator which can be deleted.

...There are old cars,and then there are Classics..(Mercedes Benz Ad. 1999)
Gregory
1/24/2007 7:28 PM
I ordered the reseal kit for the pump; it should be here tomorrow. Does anybody know if the kit comes with the o-rings for the positive and negative terminals?
Chris Johnson
1/24/2007 10:40 PM
Just a quick comment.

I rarely get into the late style horizontal pumps, but I doubt that fuel should even be able to get to the point where it is coming out past the wire terminals.

If this pump is anything like the original style pumps, there is a seal between the fuel section and the motor. This seal is not just a simple O-ring. This fault is what generally puts these pumps in the hands of a professional rebuilder.

The point is to make sure you have a good seal between the fuel section and the motor, otherwise, you may be creating a bomb!

Chris Johnson
If you aren't constantly IMPRESSED with your car, then it needs fixing.
100.012-12-000790
109.018-12-000019
109.018-12-003834
www.300SE.org
Gregory
1/24/2007 11:03 PM
Sorry, I was not clear. The pump I am talking about is the "short" version pump. The second version, for the 6.3. Not the 3.5 pump.
Chris Johnson
1/24/2007 11:23 PM
The same rules apply. There should definitely be a seal between the fuel section and the motor.

Chris Johnson
If you aren't constantly IMPRESSED with your car, then it needs fixing.
100.012-12-000790
109.018-12-000019
109.018-12-003834
www.300SE.org
Ron B
1/25/2007 3:25 AM
Chris on the earlier long pump there was bleed hole which allows the fuel to run out if the seal fails,but for a reason known only to Daimler benz and Bosch ,the short pump doesn't have this hole and it is deemed uneccesary to have it.I have pulled a few apart and found the white stuff you used to get when water and petrol mixed together, in the amature windings.But they never caught fire,A lack of air would explain that I think.Better than having raw fuel dripping,and vapourising on the road from a dodgy pump.

...There are old cars,and then there are Classics..(Mercedes Benz Ad. 1999)
Gregory
2/8/2007 6:05 PM
So I resealed the pump, and not to my suprise, it's still leaking at the terminals through the orings that I did not change. I was not able to order them from the dealer. I think I need to unsolder the connections and find some o-rings of similar size. I also believe fuel IS supposed to be in the armature area; I don't think it is supposed to be a dry area.
George Des
6/27/2007 5:24 PM
Gregory,

You are correct. Unlike the long older style pump, the smaller pump has no sliding ring seal isolating the motor section from the pump section and is designed to have fuel flowing through the top "motor can" section-thus no leak off pipe. The fuel flow cools, cleans and lubricates the motor section of the pump.

The original o-rings used on the terminal section have a flat cross section, but you should be able to get a standard o-ring of correct size to work as well. These o-rings are not included in the MB repair kit. (I've been considering building kits for both this pump and the older pump that would provide more than the MB kits but have just not got around to it.) What I generally do is use the std o-ring and help it seal up with some gasoline resistant sealer--comes in the yellow tube with red writing and available at Autozone or Advance Auto. Make sure you put the "motor can" and impeller vane back in exactly as they were or you'll have a pump that operates in reverse or won't pump fuel or both. See posts on this on the Pagoda site--it happens quite often and drives people crazy trying to figure out what is wrong.. Hope this helps.

George Des
karra
6/27/2009 5:41 AM
Hello!

I had two different breakdowns today [:(!] . After having filled the tank of my 6.3 I saw few days later some fuel had leaked out. I thought the fuel expanded when our weather warmed up from 15 to 28 deg C. The problem was leaking fuel pump, the short one of course. When I started the car the leak increased. So, I had to drive back to my father's garage and saw it was leaking somewhere at the top flange or the terminal area.

I took my coupe and headed to a cruising that takes place today and felt something was wrong; one of the front brake was overheating. I pressed the pedal hard a few times and then it went all the way in... I drove back 20 km using the parking brake when needed...that is another store - now there are brakes on the car but it does not release all the way. I need to overhaul the master cylinder first.

Back to the fuel pump, I have read the topic on the rebuild of the long body pump as well.

I have now taken part the bottom cap, the pump body and have the motor part with the fuel discharge pipe in one piece of course. If I understood right the fuel is in the motor section so there are no seals there? The top O-ring looked fine so I believe the fuel is leaking at the terminals.

I thought the pump had been replaced because it looked so clean and had no corrosion. But, the blue paint was not in tact so the pump has been opened at least once.



The pumping capacity is OK, I have checked that earlier. The pump housing has some dirt build-up but only minimally - just as colour. I have driven approx 800 km with the car now and otherwise the pump has worked well.

Should I buy two new large O-rings and try to get also small O-rings for the terminals? I need to solder the wiring loose I guess. Of course I could order the repair kit and get the brushes as well.

Kari Pykäläinen

1971 6.3 #5581
1968 280 SE Coupé
1993 E420
1995 Tahoe 350cid

EDIT: I dismantled the motor as well, It is indeed designed to be filled with fuel. I soldered out the wiring for the terminals.







karra
6/29/2009 11:00 AM
Does anyone rmember which way the vanes should be at the impeller? I can not tell exactly which way it was. I can try to figure out thinking of the way it pumps... I first have to see which way it rotates.

The vanes are not equal thick; the shape is a bit like a wegde. I would guess the thicker part goes towards the electric motor. I am planning to assemble the pump - I got new viton o-rings for the terminals but could not get any other o-rings locally. My dealer sent an enquiry to Classic Center because the overhaul kit seems not to be available any more. The EPC showed the part number but not possible to order by the usual way.

Kari Pykäläinen

1971 6.3 #5581
1968 280 SE Coupé
1993 E420
1995 Tahoe 350cid

EDIT: I was able to see the direction by the dirt on the center of the impeller. In the pump housing where the impeller rotates is no dirt, but over that housing, in the "pressure chamber" there was black dirt that I cleaned away with brake cleaner.

Anyhow, the thicker part of the vane is on the bottom - opposite that I was guessing first.

The viton o-rings I got are most likely too thin - I need to find ones that give better seal. The o-ring needs to be tight enough in the start already, the terminal plugs do not squeeze in so much that the o-ring expands when pressed. Also there is only one screw to hold the terminals in place and that is not enough to create the pressing on the o-rings - they need to fit tight in the beginning already.

Probably I will install NBR (nitrile rubber) o-rings because those are used in hydraulics. The shop told me viton is better for gasoline though but the right size is not available.
karra
6/30/2009 4:01 PM
Today I visited an industrial elastomer supplier that we use when we need hoses and seals etc. at my work.

They had everything available in Viton: http://www.timcorubber.com/materials/viton.htm

So I ordered all the o-rings and for the terminals I will get both 8 x 2 and 8 x 2.5 mm sizes because the terminal plug is a bit conical (will need to see which size is right). I will make a list what is needed if the overhaul work turns out to be successful.

The sales engineer at the shop told me that in 1971 Viton was not available so the original o-rings are most likely nitrile rubber. But, gasoline today has a lot of additives and also the ethanol that is added in Scandinavia can cause a need of better elastomer quality than nitrile is. Who knows.

Kari Pykäläinen

1971 6.3 #5581
1968 280 SE Coupé
1993 E420
1995 Tahoe 350cid
karra
7/3/2009 3:23 PM
I have been struggling with the pump all afternoon.

I assebmled the pump with the 8 x 2 mm o-rings for the terminals. When putting the "pressure chamber" together with the motor section I saw the 71.5 x 2.4 mm o-ring was much too thick in order to close the flanges all the way. I managed to connect the parts together by compressing the unit on a bench. The bottom cap was OK with the same size o-ring.

But, it leaked after my 10 km test drive. I assumed the leak was from the terminals because it looked that way. I replaced the o-rings with thicker 8 x 2.5 mm ones. I saw the big o-ring between the motor and ther "pressure chamber" was already deformed but still assembled all the way. Then, it leaked immediately from that flange connection. I saw the big o-ring had damaged badly; it was cut in half almost all the way.

I measured the space for the o-ring and saw it is only 0.3 mm gap, but there was approx 1.5 - 2 mm thick o-ring in place. I managed to source out a large viton o-ring having 1.7 mm thickness after working hours still. I needed to cut it and glue back to proper diameter. But, superglue does not work with viton. I found one old nitrile o-ring that I glued to correct size and tried that, but it still leaks from that flange.

Can it be that on that connection there is a gasket instead? The place is not good for an o-ring as it can slip away when pressing the flanges together. I did not find any information in my shop manual.

My dealer said the repair kit contains two larger o-rings and one smaller. Can it be like this:
-one approx 55 mm for the motor housing
-one approx 71 mm for the bottom cap
-one approx 18 mm for the shaft in the "pressure chamber"

In this case there is no seal (o-ring) between the motor and the "presure chamber" ? Maybe I can use the red engine sealant (oil & gasoline resistant) that comes in a tube. Plus a paper gasket that I can cut out.

Has anyone tried a simple in-line fuel pump, like DB Depot in Germany suggest on their website?





Kari Pykäläinen

1971 6.3 #5581
1968 280 SE Coupé
1993 E420
1995 Tahoe 350cid
karra
7/3/2009 5:53 PM
I found out from detali.ru that the repair kit contains 3 sizes of o-rings and the brushes. This backs up the theory that the one connection is without an o-ring.



But, o-rings no. 164 and 167 are available separately, what might those be? And is this picture for the long or short pump?

Anyhow I will try to fabricate a paper gasket for that place and add some engine sealant.

Kari Pykäläinen

1971 6.3 #5581
1968 280 SE Coupé
1993 E420
1995 Tahoe 350cid
paul-NL
7/3/2009 6:07 PM
Hi Kari,

that pump of DB Depot looks like a 6.9 pump. I suppose it is ..

Chris Johnson
7/3/2009 6:28 PM
And the pump in the picture is a long-body pump, not the short.

Chris Johnson
If you aren't constantly impressed with your car, then it needs fixing.
100.012-12-000790
100.012-12-000867
www.300SE.org
paul-NL
7/3/2009 6:34 PM
Chris,

could both pumps not have the same Diameter, so the repairkit is for both pumps the same ???

Chris Johnson
7/3/2009 6:48 PM
The only repair kit I can get has just the motor brushes, no seals. However, I don't think the parts are interchangeable since the long body pump is a "dry" pump and the short body is a "wet" pump. The kit for the long pump wouldn't have any o-rings except for the bottom cover.

Chris Johnson
If you aren't constantly impressed with your car, then it needs fixing.
100.012-12-000790
100.012-12-000867
www.300SE.org
Art Love
7/4/2009 1:53 AM
The kit 000 586 01 47, shown in the parts manual is for the short pump. While the diagram shows the long pump (they did not change the diagram when they changed the pump), the kit is coded as only applicable after chassis #2195 which was when the cars were routinely fitted with the short pump. If there ever was a repair kit for the long pump (??000 586 00 47), it has not been available for a long time. When I bought the repair kit 000 586 01 47 over 10 years ago, it contained two brushes and 2 or 3 O rings, but the last I heard, it was NLA. The brushes were definitely different from those in the long pump. The O rings shown in the parts diagram labeled 164 and 167 used to be numbered 53 and 54 and were 000 997 91 45 and 004 997 04 45 and were for the top cap and bottom plate of the long pump, not the short pump. They were coded accordingly as applicable up to chassis #2194. If these part numbers have been changed, they may now be for the short pump, but if they are the same, then these O rings probably will not fit the short pump. I have no experience in trying to repair these short pumps, but in the long pump, the O rings with the exception of the troublesome one on the shaft by the bellows seal are readilly available commercially. With the short pump available new, I would rather buy a new one than spend hours trying to reseal an old one. My obsession with trying to repair the long pumps is no more than an originality thing. Don't know whether this is helpful, but I hope so.
Art
karra
7/4/2009 2:08 AM
Thanks for comments.

My dealer searched from EPC with my VIN number that a repair kit has been available. It seems to contain the parts shown in the picture from Detali.ru-site. That tells me that there is no o-ring at the connection which I am struggling with.

Beacuse I am almost ready with the pump I will try to seal the leaking connection, one more time.

I also think I'd rather buy the original pump and not the "aftermarket" one (or 6.9 version).

But, I have got the short one of course (wet) and it should be the same in the picture I posted from DB Depot.

Within few hours I have more news [:D] .

Kari Pykäläinen

1971 6.3 #5581
1968 280 SE Coupé
1993 E420
1995 Tahoe 350cid
karra
7/4/2009 12:57 PM
Ok, now my pump does not leak anymore [:)] .

The connection between the "pressure chamber" and the "terminal bridge" is still a mystery. I measured again the space for the o-ring from inside part of the housing and it seems there is no gap at all. So that is why my 2.4 mm thick o-ring damaged immediately. I installed the old o-ring from the bottom plate so that it is located right at between the flanges - still there is no space reserved for an o-ring but the used one was soft and it provided the needed seal.

I will try to find out what kind of o-rings the repair kit contains, if possible.

Here is what I used:
8 x 2.5 for the terminal plugs
18 x 2.5 for the shaft at the "pressure chamber"
55 x 2.0 for the motor top cap
70.5 x 2.4 for the bottom plate
71.5 x 1.8 for the motor housing (terminal bridge) that connects to the "pressure chamber"

Perhaps the 8 x 2.0 provide the needed seal for the terminals but the 8 x 2.5 mm work well.





Kari Pykäläinen

1971 6.3 #5581
1968 280 SE Coupé
1993 E420
1995 Tahoe 350cid
George Des
7/9/2009 7:32 AM
Karra,

The small pump like the larger pump can be successfully rebuilt so that the fuel flow and pressure are restored. As others have pointed out though, the repair kits for the larger pump are NLA and the kit for the smaller pump, if available, contains only a minimum number of parts, i.e. two or three o-rings and the brushes. I've found that with some of the MB provided small pump repair kits, the brushes included do not contain a relief cut in the shunt area as the original does to facilitate installing them. Also as pointed out, the small pump is a wet pump and fuel is indeed intended to flow through the top portion of the pump. One area that habitually leaks, as you've found out, with these pumps is the terminal area. This is caused by the deterioration of the o-rings behind the terminals and unfortunately these rings are not supplied with the repair kits. The reason you are having difficulty sealing this area is because the o-rings are of a square cross section and are not normally available unless you special order through an o-ring supplier. I have had good luck with rounded cross section o-rings though by re-inforcing them with some fuel resistant sealer such as SEAL-ALL--not ideal, but it will work. I would stronly advise against using a gasket on the bottom plate. I have been able to find o-rings in Nitrile that with a little stretching, will fully seal this area. The Nitrile is fuel compatible and has sufficient "memory" to hold the stretch while you replace the bottom plate and re-install the screws. I'll look around and find out what size I have been using and let you know. For further info on how to rebuild both pumps, see the Tech Manual section of the SL113 website.

Hope this helps,

George Des
karra
7/9/2009 6:13 PM
Hello George!

Today I got the individual part n:os from my dealer for the repair kit. At the moment the parts list is in my Chevy and I am 500 km away from home at a Historic race event. I will post the numbers next week if we can sort out what belongs to where. But, they were not sure about the availability. Could someone please explain what NLA means, I guess not available or something like that [:)]

Today I ordered a thinner Viton o-ring just in case if the old one starts to leak. The size is 69.5 x 1.78 mm and will probably fit between the motor unit and pump housing (the one a was struggling with most).

Kari Pykäläinen

1971 6.3 #5581
1968 280 SE Coupé
1993 E420
1995 Tahoe 350cid
Art Love
7/9/2009 11:55 PM
Hi Kari,

Sorry about that. NLA = No Longer Available.
Art
George Des
7/10/2009 6:48 AM
Karra,

Don't be to shy about stretching a smaller one slightly to fit. I've never worked with the Vitron ones since I think it may be a little overkill, but the Nitrile ones will stretch to fit and provide a good tight, fuel resistant seal.

George Des
karra
7/25/2009 1:07 PM
quote:
Originally posted by karra

Today I got the individual part n:os from my dealer for the repair kit. At the moment the parts list is in my Chevy and I am 500 km away from home at a Historic race event. I will post the numbers next week if we can sort out what belongs to where.


OK I found the list. The kit is NLA but the o-rings are available, and this means the brushes are not any more available.

The o-rings are:
99 A 010 997 50 45
99 A 010 995 51 45
99 A 010 997 49 45

I have got the last missing o-ring now in my glove compartment, made of Viton. If the old one starts to leak then I will change it.

Kari Pykäläinen

1971 6.3 #5581
1968 280 SE Coupé
1993 E420
1995 Tahoe 350cid
karra
3/28/2012 6:53 AM
Talking about the "short pump", is it similar like the 6-cylinder cars have?

I have opened the bottom cover of my 230 SL pump and the impeller is fixed at the shaft with a wedge that is no longer original in my car. It is self-made of brass and is not with a tight fit.

Can I buy the wedge from somewhere or I could fabricate a new one if I had the correct dimension?

Kari Pykäläinen

1971 6.3 #5581
1987 560 SEC
1993 E420
1995 Tahoe 350cid
1982 Stingray SV175 boat

EDIT the part I was referring is of course a woodruff key. I found on the pagoda website:

When you remove the Impeller there will be a very small woodruff key (made of hardened steel 2 x 1.5 x 1.5mm) in that square cut out. Keep that woodruff key very safe. There is a small flat area ground on the shaft that locates the Woodruff Key and when assembled it stops the impeller from spinning on the shaft.

The dimension seems to be odd; I can not figure out how such a part fits on the slot at the shaft.
AgSilver
3/4/2013 11:09 AM
During the restoration I installed a Mallory Comp140 pump. Drove the 6.3 in NYC last June with 100+ deg temps. No issues whatsoever. It has proven to be absolutely reliable. The pump is, however, a bit louder than the Bosch. It's also a common retrofit to 8 wheelers as it is also considered to be very reliable. Just my .02.
Jack English
3/6/2013 12:05 AM
I recently replaced my fuel pump because of worn out carbon brushes, not leaking. I asked Tom Hanson for a rebuild kit for the old one but that is NLA. Is there a source for repacement brushes?

Jack English
300SEL 6.3 #4768
George Dez
3/6/2013 2:27 PM
I had made up some repair kits for the large style pump that included the brushes, bearings, orings, tab washer, circlip and woodruff key. Sold many of these to the memebrs on the Pagoda site.

George Desiderio
Jack English
3/7/2013 12:23 AM
Mine is a 1971 with the later pump. It works quite well if you whack it with a hammer a couple of times when starting the car.

Jack English
300SEL 6.3 #4768
AgSilver
4/28/2013 12:18 PM
Replace your rotten Bosch with a Mallory Comp 140 series and you will never have a fuel pump problem again. Started my heat soaked engine in 101F ambient last year in NYC in 2 seconds. Later I was stuck in NYC traffic for an hour with the AC on. OEM aux fan kept coolant temps below 200F at all times. No problem. And never a problem here in Florida. MFI pump by Robert Fairchild of Jerry Fairchild Industries. His grandfather (Jerry) did all my Bosch work in LA during the 50's and 60's. Robert set up the pump to compensate for the 104.5mm Mahle's and a little more aggressive cam timing.
Ron B
5/5/2013 9:59 PM
What sort of Cams are you running?
[:)]

quote:
12-14-2004, 11:49 PM #8
Tom Hanson
MBCA Member

What the heck, try to stuff a MB 6.9 liter V8 in it. What a machine that would be..
__________________
Tom Hanson
Orange County Section
wbain
11/18/2013 4:57 PM
I bought a 'Big end' street electric pump #10150 rated at 95 GPH 2 years ago. It's made in China and cost me $136 including some fittings. The mounting is different so I need to figure that out.


Warren Bain '65 220S, '99 Volvo V70, 2002 Ford Crown Vic Police Interceptor
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