Return to the home page...

Go Back   Moyer Marine Atomic 4 Community - Home of the Afourians > Discussion Topics > Fuel System

Reply
 
Thread Tools Display Modes
  #1   IP: 204.157.20.46
Old 10-12-2004, 01:40 PM
Don Moyer's Avatar
Don Moyer Don Moyer is offline
 
Join Date: Oct 2004
Posts: 2,811
Thanks: 0
Thanked 180 Times in 122 Posts
Mechanical fuel pump rebuild services

After adding rebuilding kits and stainless sediment bowls to our online catalog in February and March, we continued looking into ways to make the mechanical fuel pump more reliable.

It quickly became apparent that the condition of the upper housings was the single most critical threat to the pump's reliability and safety. Approximately half of the old mechanical pumps we had stockpiled for rebuilding proved to have unusable upper housings due to corrosion, warping over the sediment bowl or hairline cracks around the inlet and outlet fittings. Developing a new and stronger upper housing therefore became central to our efforts in supporting the mechanical pump option.

With this background, if your mechanical fuel pump malfunctions, or when it comes time to rebuild the pump by virtue of age, we suggest the following progressive approach:

1. Disassemble your pump, and check the condition of the major housings. If they are in good condition, including a good fit between the sediment bowl and the underside of the upper housing, you should be able to rebuild your pump using one of our mechanical fuel pump rebuild kits.

2. If you discover that your upper housing is in good condition, except for a noticeable downward bow above the sediment bowl (where the bail attaches to the housing) which causes the bowl to rock back and forth when checking the fit without the rubber washer, you can most likely straighten this part of the housing using our mechanical fuel pump repair tool.

3. If you discover that your upper housing is not usable, but the rest of the pump is in good condition, you could opt to simply replace the upper housing with one of our new (improved) upper housings . This would be an especially attractive choice in cases where you may have previously rebuilt your pump and subsequently discovered a leak around one of the fittings.

4. If your pump looks like the proverbial "basket case", you can opt for either a rebuilt original pump or an MMI mechanical fuel pump which incorporates a new upper housing and stainless sediment bowl.
Reply With Quote
  #2   IP: 24.190.86.12
Old 10-21-2004, 05:36 PM
shemandr shemandr is offline
Senior Member
 
Join Date: Oct 2004
Location: greenport ny
Posts: 31
Thanks: 0
Thanked 1 Time in 1 Post
fuel pump rebuild

i have the mechanical fuel pump rebuild kit. the instructions show the disassembly of the pump off the engine. i don't have good access to the engine in that area and cannot see how the pump can be taken off the engine.
the rebuild seems to require access to two bolts/screws on the bottom of the pump, removal of the priming bale and removing a pin through the diaphram post.. i can't see doing this with the pump on the engine.
how can i remove the fuel pump?
Reply With Quote
  #3   IP: 209.163.125.134
Old 10-22-2004, 06:36 AM
Don Moyer's Avatar
Don Moyer Don Moyer is offline
 
Join Date: Oct 2004
Posts: 2,811
Thanks: 0
Thanked 180 Times in 122 Posts
The pump is mounted with two 1/2" hex-headed bolts. The forward bolt is usually rather easy to remove, but access to the rear bolt is restricted by the sediment bowl. If you can loosen the bail and remove the bowl, the rear bolt will be a bit easier to handle. For years I've been using a cheap 1/2" socket, which I ground quite thin around the front, to squeeze past obstructions and get to the rear bolt. I use a 3/8" extension approximately 6" long, and I've always able to get the rear bolt to turn, even though it isn't always possible to get the socket on straight.
Reply With Quote
  #4   IP: 24.190.86.12
Old 10-22-2004, 09:00 AM
shemandr shemandr is offline
Senior Member
 
Join Date: Oct 2004
Location: greenport ny
Posts: 31
Thanks: 0
Thanked 1 Time in 1 Post
Smile

thanks for the tip. i think this is going to require an access port in the 1/4 berth locker. i glad to know what i'm after before i cut up the boat!
Reply With Quote
  #5   IP: 68.108.68.241
Old 10-22-2004, 10:47 AM
Bob Grenier's Avatar
Bob Grenier Bob Grenier is offline
Senior Member
 
Join Date: Oct 2004
Posts: 29
Thanks: 0
Thanked 0 Times in 0 Posts
I have found that if you replace the mounting bolts with Allen-head bolts it makes replacing them a lot easier as socket clearance is no longer a problem. Also because a lot of time the back bold is done by feel only.
Reply With Quote
  #6   IP: 24.190.86.12
Old 10-26-2004, 12:42 PM
shemandr shemandr is offline
Senior Member
 
Join Date: Oct 2004
Location: greenport ny
Posts: 31
Thanks: 0
Thanked 1 Time in 1 Post
feel only is an understatement. it took about two hours of contortionism. bleeding hands and a good patch of blue air to get that rear bolt out. i like the allen type bolt idea. thanks.
Reply With Quote
The Following User Says Thank You to shemandr For This Useful Post:
Theo Lewis (03-01-2021)
  #7   IP: 24.190.86.12
Old 10-29-2004, 10:26 AM
shemandr shemandr is offline
Senior Member
 
Join Date: Oct 2004
Location: greenport ny
Posts: 31
Thanks: 0
Thanked 1 Time in 1 Post
one question on the rebuild of the fuel pump: since the lower housing cover came off with an explosion of springs and associated parts i did not get to examine the placement of same. i surmized from the picture that the two springs are placed, one on the rocker arm and one on the end of the rocker arm over the end of the plunger/diaphram. they then fit the hubs on the cover on the other end. is that correct? assembled this way i get a healthy squirt of gas using the priming lever, and similar noise if i engage the end of the rocker arm and push it with a screwdriver.
Reply With Quote
  #8   IP: 69.72.48.119
Old 11-02-2004, 03:31 AM
Don Moyer's Avatar
Don Moyer Don Moyer is offline
 
Join Date: Oct 2004
Posts: 2,811
Thanks: 0
Thanked 180 Times in 122 Posts
I would have to say that you have most likely gotten your pump back together properly.

Don
Reply With Quote
  #9   IP: 24.190.86.12
Old 11-02-2004, 09:02 AM
shemandr shemandr is offline
Senior Member
 
Join Date: Oct 2004
Location: greenport ny
Posts: 31
Thanks: 0
Thanked 1 Time in 1 Post
happy ending

the pump, the carbuerator and new racor filter are all installed and the engine runs smoothly. i don't know if the stalling problem is solved because that could happen after an hour or more of smooth running.
after installation of the filter, and before removal of the mechanical fuel pump and carbuerator for the rebuild, there was a gas odor. yes, i did spill gas cleaning the bowl to the fuel pump and cutting the fuel line for the filter. but it seemed like there was some gas in the throat of the flame arrester. i haven't decided if it still exists after the rebuilds. i am wondering: i put the fuel filter a bit higher than the fuel intake to the fuel pump to allow access to the bottom of the filter for draining. is the only safeguard keeping fuel from filling the float chamber, and hence overflowing into the air intake, the quality of the needle valve seat?
i could install a longer fuel line with a dip below the level of the fuel intake to discourage gravity flow from the filter when the engine isn't running. the fuel tank pick up is on the top of the tank and is above or level with the fuel pump intake.
Reply With Quote
  #10   IP: 204.157.20.43
Old 11-02-2004, 08:41 PM
Don Moyer's Avatar
Don Moyer Don Moyer is offline
 
Join Date: Oct 2004
Posts: 2,811
Thanks: 0
Thanked 180 Times in 122 Posts
You really should have a manual fuel valve somewhere ahead of the carburetor, so that you can positively shut off the fuel to the carburetor while you're away from the boat. While it's true that a perfect float valve will keep fuel from collecting in the throat of the carburetor indefinitely, all it would take is a "fly-speck" piece of crud to hold the float valve open.

Regards,

Don
Reply With Quote
  #11   IP: 24.190.86.12
Old 11-05-2004, 11:54 AM
shemandr shemandr is offline
Senior Member
 
Join Date: Oct 2004
Location: greenport ny
Posts: 31
Thanks: 0
Thanked 1 Time in 1 Post
Yikes!

that needle valve doesn't seem like enough security for my taste. one good thing about doing this myself is gaining an appreciation for issues like this. if i paid a mechanic to do this i wouldn't have given it a second thought.
there is a shut off on top of the fuel tank about six feet away. that still leaves fuel in the in the fuel line and fuel filter, which could flood the carburetor if the vacuum from the tank to the carburetor were broken. do you think i need a shutoff, say between the fuel filter and the carburetor?
Reply With Quote
  #12   IP: 204.157.20.43
Old 11-05-2004, 02:42 PM
Don Moyer's Avatar
Don Moyer Don Moyer is offline
 
Join Date: Oct 2004
Posts: 2,811
Thanks: 0
Thanked 180 Times in 122 Posts
Placing a valve just ahead of the carburetor would be the most conservative approach, especially for long absences from your boat.

However, if your needle and seat has chronic problems of leaking, it would be good to know it, since a leaky float valve will lead to a rich running condition. For this reason, you may want to leave the valve just ahead of the carburetor open while you're on the boat to observe it from time to time.
Reply With Quote
  #13   IP: 209.86.105.127
Old 11-27-2004, 02:40 AM
HOTFLASH HOTFLASH is offline
Senior Member
 
Join Date: Oct 2004
Location: Chicago
Posts: 210
Thanks: 29
Thanked 26 Times in 21 Posts
Is valve at the fuel tank good enough?

Quote:
Originally Posted by Don Moyer
You really should have a manual fuel valve somewhere ahead of the carburetor, so that you can positively shut off the fuel to the carburetor while you're away from the boat. While it's true that a perfect float valve will keep fuel from collecting in the throat of the carburetor indefinitely, all it would take is a "fly-speck" piece of crud to hold the float valve open.

Regards,

Don
Or is another one needed? Is there a way to regulate that valve from the cockpit without having to open the engine compartment?
Reply With Quote
  #14   IP: 204.157.20.43
Old 11-27-2004, 08:23 AM
Don Moyer's Avatar
Don Moyer Don Moyer is offline
 
Join Date: Oct 2004
Posts: 2,811
Thanks: 0
Thanked 180 Times in 122 Posts
The basic concept of a manual valve sort of dictates that it would be located in the fuel line itself, and at a location that best protects the boat from a fuel leak while it (the boat) is unattended.

You could no doubt find a valve with a remote control feature to turn the fuel off and on from the cockpit during the time you're on board (an electric solenoid comes to mind), but then you'd probably still want to have a manual valve to back up the remote controlled system when the boat is unattended. I would list a manual fuel valve in the same category as a through-hull, where there's really nothing quite like "putting your hand on a valve" to give you the security you're looking for.

Best regards,

Don
Reply With Quote
  #15   IP: 67.112.242.49
Old 07-05-2005, 05:37 PM
mingamells mingamells is offline
Senior Member
 
Join Date: Apr 2005
Posts: 11
Thanks: 0
Thanked 0 Times in 0 Posts
Question Fuel Pump Rebuild Kit

Currently, my fuel pressure is 5.5 psi with (apparently) the standard mechanical fuel pump. Would your rebuild kit reduce the fuel pressure to typical levels (3-4 psi)?

Thanks in advance.
Reply With Quote
  #16   IP: 38.118.52.61
Old 07-07-2005, 07:16 AM
Don Moyer's Avatar
Don Moyer Don Moyer is offline
 
Join Date: Oct 2004
Posts: 2,811
Thanks: 0
Thanked 180 Times in 122 Posts
Post

Yes, but unless you're experiencing problems (flooding of the intake throat of the carburetor etc.) 5.5 psi doesn't usually present a problem.

Don
Reply With Quote
  #17   IP: 66.245.131.21
Old 08-18-2007, 11:36 PM
HOTFLASH HOTFLASH is offline
Senior Member
 
Join Date: Oct 2004
Location: Chicago
Posts: 210
Thanks: 29
Thanked 26 Times in 21 Posts
Question Looking for Allen head Mech fuel pump bolts

Anyone know a source for Allen head bolts to attach the mechanical fuel pump to the engine?
Reply With Quote
  #18   IP: 70.173.53.189
Old 08-19-2007, 01:20 PM
Bob Grenier's Avatar
Bob Grenier Bob Grenier is offline
Senior Member
 
Join Date: Oct 2004
Posts: 29
Thanks: 0
Thanked 0 Times in 0 Posts
Allen head bolts

Any good Auto parts center or Home center will have what you need...Just bring your old bolt and match the thred and size.
Reply With Quote
  #19   IP: 138.162.0.41
Old 10-15-2007, 01:44 PM
Dana Paterson Dana Paterson is offline
Senior Member
 
Join Date: Sep 2007
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
Mechanical Fuel Pump Removal

I just removed the Mechanical Fuel Pump from my Atomic 4 this last weekend and replaced it with a blanking plate. Not knowing that it was supposed to be very hard, I approached it from the flywheel side. To put light on the subject, I positioned myself in front of the flywheel and shined a powerfull flashlight through the slot between the spark arestor and the valve cover. This illuminated the front bolt quite nicely. I then reached around the carb with a 3/8" drive equipped with a 3" extension and a 1/2" socket. First bolt off...no problem. I then removed the extension from the drive leaving the socket on the extention and probed for the rear bolt until I found it. Leaving the extended socket on the bolt, I reached back and clicked the drive onto the extension and backed the second bolt out. Again...no problem.

What i want to know, Don, is should I have left the push rod in place when I put the blanking plate on? I saw no reason to do so and removed it and put the blanking plate and new gasket (with sealer) on. Now, I'm thinking about the little hollow spot machined into the pushrod side of the plate and hoping that I haven't done something really stupid. a quick answer would be appreciated.

Where would I be without this site! Thanks.
Reply With Quote
  #20   IP: 38.118.52.41
Old 10-16-2007, 06:59 AM
Don Moyer's Avatar
Don Moyer Don Moyer is offline
 
Join Date: Oct 2004
Posts: 2,811
Thanks: 0
Thanked 180 Times in 122 Posts
Dana,

Congratulations on performing a very difficult task with apparent class and dignity which many of would have felt the need to resort to a bit of "colorful" language before finishing. You were correct to leave out the little pushrod. In fact, if you had left the rod in place, it would have pushed out through the thin layer of metal at the end of the recessed area
in the cover plate.

Don
Reply With Quote
  #21   IP: 75.41.6.169
Old 10-16-2007, 05:07 PM
marthur's Avatar
marthur marthur is offline
Afourian MVP
 
Join Date: Dec 2004
Location: Grand Rapids, Michigan
Posts: 831
Thanks: 25
Thanked 33 Times in 28 Posts
Magic Words

That colorful language I prefer to call the "magic words" because it has helps me through the most difficult part of the job ; )
Reply With Quote
  #22   IP: 72.88.69.239
Old 07-30-2008, 09:39 AM
keithems keithems is offline
Senior Member
 
Join Date: Feb 2008
Location: buffalo, ny
Posts: 376
Thanks: 6
Thanked 20 Times in 20 Posts
removed my mechanical fuel pump last nite -- not very hard -- used a 3/8 drive with a 14 mm socket [it's all i had -- but maybe it had just enuf flex to grab the bolt without stripping it?] -- and most importantly -- a 1" extension called a "wobbly" -- one of my favs for when i can't grab a bolt head directly -- also, to be fair -- my c&c 30 has lots of working room -- esp. since i'm rehabbing and removed the plywood sheathing around the engine compartment -- frankly, i may well leave it off, since i always want to be able to get at my engine easily -- and when you hide the engine, u neglect it and they get that pathetic rust covered look [as opposed to the glamorous rustoleum red look mine has ]

ok -- now my question -- i thought my fuel pump was shot cuz the primer didn't move and the line was totally dry -- but once i had it off, the primer moved and pumped fuel out of the tank for me -- so i reinstalled it -- and -- once again, the lever won't move, though i think the fuel is flowing -- motor had run fine, then a few days ago, just quit 5 sec. after start up -- ever since -- nothing -- i also installed a groco 376 fuel filter last nite [says filters down to 3 microns] and pulled the carb and fuel pump drains -- the fuel doesn't look that bad -- so i'm wondering -- seeing as no coughing, misfiring, etc. -- is it really an ignition problem? -- i had loosened the distributor on that last startup [i know, i know -- should have done that after start, not before] but since then i've reset the timing to tdc and tightened it back down....
Reply With Quote
  #23   IP: 142.68.109.158
Old 09-07-2008, 05:59 AM
rigspelt's Avatar
rigspelt rigspelt is offline
Afourian MVP
 
Join Date: May 2008
Posts: 1,187
Thanks: 0
Thanked 18 Times in 17 Posts
Quote:
Originally Posted by keithems View Post
ok -- now my question -- i thought my fuel pump was shot cuz the primer didn't move and the line was totally dry -- but once i had it off, the primer moved and pumped fuel out of the tank for me -- so i reinstalled it -- and -- once again, the lever won't move, though i think the fuel is flowing (snipped)
If you are referring to the manual pumping bail on the mechanical fuel pump: mine would not move when I gingerly tried it before the mechanic arrived to give my "new" old A4 a good inspection after buying the boat. He said it was because of where the crankshaft had stopped. We turned the shaft a bit and it pumped fine. Does that describe your situation?

UPDATE: I later discovered this INvaluable tidbit by Don Moyer: http://www.moyermarine.com/forums/showthread.php?t=827
__________________
1974 C&C 27

Last edited by rigspelt; 09-07-2008 at 06:38 AM.
Reply With Quote
  #24   IP: 98.150.171.105
Old 11-30-2009, 02:32 PM
ryanmohr ryanmohr is offline
Frequent Contributor
 
Join Date: Nov 2009
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
I too had an explosion of springs and parts when I opened up my pump. I ended up losing one of the spring caps under the engine and can't get to it.

Everything else on the pump is in decent condition so I don't need a full kit. Where can I purchase the little spring caps? Is it possible to pick up a replacement at a local hardware or auto supply store?
Reply With Quote
  #25   IP: 76.241.85.255
Old 09-22-2010, 05:43 PM
jerrysingle jerrysingle is offline
Frequent Contributor
 
Join Date: May 2010
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Fuel Pump Saga

A few months back I was engaged in the exercise of rebuilding a fuel pump which led to buying a rebuilt fuel pump which led to a leak in the sediment bowl and ordering gasket and stainless bale.

Now I cannot stop leaking from the sediment bowl. The gasket that came with the rebuilt fuel pump leaked almost immediately. Tightening broke the bale threading connection so we ordered the bale and gasket The gasket appears a quarter inch smaller in diameter than the replacement and very hard.

Now installing the new bale and new gasket ... the sediment bowl is still leaking.

Any thoughts?
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 02:04 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2023, vBulletin Solutions, Inc.


Universal® is a registered trademark of Westerbeke Corporation

Copyright © 2004-2023 Moyer Marine Inc.

All Rights Reserved