dodgeman01

I heard about a washer that I could grinde down to get a lil more fuel. Well upon insection I don't have that washer in my pump I talked to Frosty about it in Chat and he told me to look at the wear mark of the fueling pin and see if it goes above the cone :- I was the first person to take apart this pump and it was not there from the factory and the truck ran really slow : I turned the diaphram to the most fuel setting and have the fuel screw turned until I can't turn the idle back down. Truck runs ok but not as well as I would have hoped it to run. is this missing washer a bad thing??
DM01
Thankx

Alec

Did you check the wear mark? On my truck, and every one I have heard about, without the washer the eccentric would be able to extend so far as to start cutting back on the fuel (pushing the pin in) again. I would also think it would be tough on the diaphragm, running with no stop. Did you check the rubber for tears, etc.?

If the wear mark is extending past the deepest part of the eccentric, then you should put a washer in there to stop it at the deepest point in the eccentric.

Good luck,

Alec

Monty

If I run mine without the nylon washer. It is a complete dog. 10psi max on boost.

As aslitch said, this can cause premature wear on the internals and especially on the fuel pin if it is allowed to go above the lobe on the eccentric.

dodgeman01

If I knew what the washe looked liek and how big a round and thick it was I could just find one to put back in there. as for rigth now The truck runs good but smoke is down a lot from what it use to be before I got it back from the pump shop. I wander if the washer had something to do with my pump going out. >
DM01

Alec

I just have a couple copper washers in mine. The original washer does not have a very wide flat (o.d. is not much greater than i.d.) so as long as what you put in there doesn't interfere with anything else, I don't think it matters that much, as long as it is the correct height and doesn't bind on the eccentric. If you want to get fancy, you can get a nylon bushing from the hardware store and cut it down to the correct height.

Here is a suggestion for determining the correct height:

Take your eccentric out, get some washers that fit around the eccentric shaft and stack them up to about 3/8" under the diaphragm, put a light coating of grease on the eccentirc (so that the pin leaves a tell-tale mark in the grease), put the eccentric in without the spring, pull the accelerator crank to wide open and slide the eccentric up and down a little at the same time to make a mark in the grease, let off the accelerator, take the eccentric out, measure how far from the bottom of the eccentric your tell-tale is, and take that amount away from the height of your washer stack to determine the optimal height.

Monty

A good substitute for the nylon washer is a square cut o-ring. Find one about 1/8" thick and see how you like it. Lots of guys have done this with no problems what-so-ever

dodgeman01

[quote author=Monty(OkieBroncRider) link=board=9;threadid=20187;start=0#msg190805 date=1064889313]
A good substitute for the nylon washer is a square cut o-ring. Find one about 1/8" thick and see how you like it. Lots of guys have done this with no problems what-so-ever
[/quote]
Square cut O-ring : where do I get one of theese. I also heard that if you wanted a lot of smoke you could take the spring out and put it on top of the diaphram ??? can I do this will it hurt anything? I really like smoke.
DM01 8)

Alec

IF you put a washer under the diaphragm, taking the spring out will give you plenty of smoke and only hurt the environment/cause excessive soot contamination of engine oil, etc. Though there was a study done in Australia that indicated that diesel exhaust was an anti-carcinogen . . . Makes you wonder what sort of controls they had in that experiment.

By the way -- if the pump was just rebuilt, can't you get teh shop to give you the stock washer, since it seems as though they left it out?

dodgeman01

[quote author=asilitch link=board=9;threadid=20187;start=0#msg191350 date=1065021427]
IF you put a washer under the diaphragm, taking the spring out will give you plenty of smoke and only hurt the environment/cause excessive soot contamination of engine oil, etc. Though there was a study done in Australia that indicated that diesel exhaust was an anti-carcinogen . . . Makes you wonder what sort of controls they had in that experiment.

By the way -- if the pump was just rebuilt, can't you get teh shop to give you the stock washer, since it seems as though they left it out?
[/quote]
The spring was never in there. I took the pump apart the first time and looked for the washer only to find it was not there. shortly after the pump tune ups I did the pump started shooting fuel everywhere and had to be rebuilt.
DM01

Monty

Either a square cut o ring ( like your oil filter o ring) or a round cut o ring (probably what you are thinking) will work. Sorry I got you confused.

ramguy

The origonal thickness of the nylon bushing is .163"

ramguy

formula

[quote author=dodgeman01 link=board=9;threadid=20187;start=0#msg191411 date=1065029019]
The spring was never in there. I took the pump apart the first time and looked for the washer only to find it was not there. shortly after the pump tune ups I did the pump started shooting fuel everywhere and had to be rebuilt.
DM01
[/quote]

Did you happen to run the engine without the eccentric cone in the pump? If so, the guide pin most likely popped out and caused the fuel leak. (been there, almost soiled my shorts, but just pushed the guide pin back in and all has been ok for about a year now) Running the afc without the spring is also not a good idea because it is possible for the cone to bind up and not give you full fueling as well as some other possible damage. As far as the washer is concerned.......... It needs to be there to prevent the shoulder of the control cone from jamming against the guide pin which places excessive lateral load on the guide pin and can limit its travel and cause wear. The minimum allowable washer thickness is approximately 0.100 inch. Here's a picture of the washer as it is supposed to sit on the control cone........

Cheers,
Sean

dodgeman01

well I took two small washers and put it in there and it seems ti ride right at the top of the cone now. before it was going up way too far. I did do one thing I put the spring back but ontop of the rubber piece. Lots of smoke is this a No no? as for the fuel leak it was on the back side of the pump. The guy at daves diesel said some kind of spring broke and took out the govenor or something heck I don't remember.
DM01

Bushy

The spring does not belong on top of the AFC diaphram. It definitely belongs UNDER it.
You can create a problem with the "on top" assembly.
Remember that the diaphram controls the cone "deflection" rate. If you put it on top it simple crams the cone down and is not what you want.
You can duplicate the effects to some degree by using the smoke screw. If you crank it down you'll end up applying some preload to the diaphram which in turn forces the cone down.
This means you are starting off with a preload on the cone at "no boost" condition.

Do it the correct way and save yourself some grief on this one bud...

Pastor Bob.

dodgeman01

I'm gonna miss the smoke :'( :
DM01