would like to get this figured out today since i got the garage warmed up and i have the day off.

im using the two piece eccentric on my 5.0L for the fuel pump. i bought a new timing chain and gears. does the back piece of the two piece eccentric spin with about a 1/16 inch space between it and the cam gear? the middle piece of the two piece eccentric is fine and tight but i really dont know if the back piece is suppose to be loose. the eccentric is brand new and the old and new timing gears have the same exact offset for the eccentric, in a word they look identical. i just dont have enough experience rebuilding engines to know. heeeelp

 

That'd be how they is. Scary looking hah? It seems a little out of place when everything else in clearanced in thousands.

 

really...... well i also have another problem after trying to mock this thing up

i bought a universal timing cover to get the oil fill hole in the timing cover and also the fuel pump boss there since the engine was originally FI. the fuel pump is bottomed out on the BASE of the cam eccentric.

im not sure but i think the eccentric always had the same offset and base circle for small block ford so im thinking i have the wrong fuel pump. the arm moves the right amount but it just sits too high....

cant imagine that the timing cover is wrong if thats for a ford small block too. the fuel pump i got is for a 79 mustang 302....were they different in some way?

 

This is where it gets tricky and confusing. The timing chain, eccentric and timing chain cover all need to be right. It is also where I get lost as to what will work and what won't. I bought a 90 something timing chain cover for my 79 351w. It looks identical to the one that came off my motor, except the fuel pump cavity is blocked off. I plan on cutting the hole out and using a mechanical pump. Anyway, my '79 came with a 2-piece eccentric, but had been rebuilt and I believe originally came with a 1-piece. A quick look at Summit was no help, but a quick look at e-bay revealed a listing for a timing cover that the guy claims is a must-have to build a Mustang. I have never heard a a fuel pump being specific to 1 or 2 pc. eccentrics, but timing chain covers and DEFINATELY timing chain sets I have. Can you post a pic of that cover? I suspect that is your problem. Also, can you tell me the timing chain model and #?

 

sure hold on

the timing cover was bought through summit ses-5-60-04-201 289-351W, 1966-93 and for some reason the picture of it in the catalog is the mirror image (which i figured out before i bought it). and the cover has everything i need in the places i need them such as the holes for the water pump i originally ran when the motor was a 5.0L out of a crown vic i owned. here it is at summit and it looks like the picture http://store.summitracing.com/partde...w=1&N=700+150+

the timing gears and chain i just put on today with no problems. it had a nice tight fit. i got that from PAW part number 515. i see in this new catalog they sent it says 1973-94 V8 255-302-351W requires two piece fuel pump eccentric (which i have).

i have plenty of room between the eccentric and the inside of the timing cover so thats not an issue.

i have also found out about the one and two piece eccentrics and the different dowel pins that they need.

would you by any chance know if the one and two piece eccentrics ARE the same as far as their geometry?

 

Is it possible to try another pump, I think except for the 351C,M,400 all the Ford fuel pumps have the same mount pattern but they do have different arms. Is the eccentric you are using from a small block or a 460, don't know the difference but in the old days the outside was the same but had a different part# for the center. I just figured it had more lift, but dont know for sure.

 

i looked online all night last night at fuel pumps and there is a difference in the arms that contact the eccentrics. i noticed some of the big block fuel pumps have arms that come almost staight out whereas the one i have (for a 79 mustang 302cid) comes out, goes up above the pump housing then down some. then there are other brand name ones like Holley that have short little arms that come out going down.

i think im going to have to call up summit and ask them who makes this timing cover and if anyone else has had any problems with the fuel pumps.

the eccentric i have is a two piece that comes in the competition cams finishing kit for ford small block windsor engines. it even says so on the little box.

was just hoping someone else had gone through this and knew what the problem was....

 

Well I hope I don't. I haven't before, but the engine that I am working on came without a fuel pump, and the arm looks similar to what you describe. I have wondered if that long arm was right since I got it, since it's been a long time since I had to replace one, and then you just match up the old to the new and if they are the same ,you don't think much about it. Let me know what you find out.

 

problem solved! woohoo

i did end up buying a holly fuel pump for a 85 mustang but it acted the same as the other fuel pump.

the two fuel pump arms moved sort of easy and a return spring moved them back but i finally got pissed off enough to really crank on them to see if they moved even more. i had tried this before but not this hard. sure enough they do and you can hear them both suck air now. have i tried fitting them yet? no but im sure if one doesnt work the other will. i can honestly say ive never had to change a mechanical fuel pump in my life before and did not know. thanks for any help and i hope this helps someone else.