2 Piece Fuel Pump Eccentric...Conflicting Info...

[Ruffi]

..regarding whether the outer ring is suppose to spin freely or not. Just torqued down the cam bolt at 40 pounds and that thing is not moving anywhere...forget about spinning around the inner diameter. Lubed the area between the two to see if that would help....nope? Need some insight...thanks.

Rob

[BMW Rider]

It is supposed to spin freely, that's the purpose of the design. The idea is it's supposed to be less friction and wear than the solid fuel pump cam. There must be some sort of clearance issue with the new gear. That said, it will work the way it is, it'll essentially be like the older one piece type.

[Ruffi]

It is supposed to spin freely, that's the purpose of the design. The idea is it's supposed to be less friction and wear than the solid fuel pump cam. There must be some sort of clearance issue with the new gear. That said, it will work the way it is, it'll essentially be like the older one piece type.

Don't like the idea of a clearance issue. It's a Comp Cams 7138 and a 2 piece design is recommended. I guess it will work although maybe I need to shim the inner piece?

[Andfab99]

Don't use it if it doesn't turn. There are different cam gears for single and two piece fuel pump eccentrics. I used the solid fuel pump eccentric years ago with the wrong gear and pushed it through the timing cover.

[Ruffi]

The cam gear is designed for a 2 piece per Comp. That's what's installed. One piece design hits the inside of the timing cover so that's not an option. Thinking about a thin washer to move out the inner piece a bit to get some clearance in there.

[Ruffi]

Decided to pull it off...used red Loctite about an hour ago and it was already setting up. When I did get it off look what I found...the backing on the inner piece was pulled into the cam gear hole and suffered stress cracks. I did properly torque this to 40 foot pounds.

Here's a pic of the old cam gear...note that the gear has a boss that allows the inner ring to seat while the outer ring can spin freely. Boss on the new gear is too large for that to happen.

Call into Comp Cams in the morning...

[Ruffi]

Don't use it if it doesn't turn. There are different cam gears for single and two piece fuel pump eccentrics. I used the solid fuel pump eccentric years ago with the wrong gear and pushed it through the timing cover.

Thinking that Comp sent the wrong cam gear with this kit...it sure is not for a two piece eccentric.

[Ethyl Cat]

It almost looks like you have a long dowel pin in there instead of a short one for the dual. Did that kit come with both pins?

Is that Race Deck flooring I see? Looks cool!

Steve

[BMW Rider]

I have two or three of the solid pump cams in my boxes of spares if you find you need one. Also have a spare two piece.

[Ruffi]

It almost looks like you have a long dowel pin in there instead of a short one for the dual. Did that kit come with both pins?

Is that Race Deck flooring I see? Looks cool!

Steve

Hi Steve,
Short dowel installed, kit did come with two. It's the boss on the gear. Measures 2.100". Stock gear measures 1.700. Just switched out the whole set with a Comp Cams 2120 which has the correct size diameter boss and what do you know, eccentric turns fine.

Floor is similar to race deck...makes it a lot easier on the feet when I'm out there all day.

[Ruffi]

I have two or three of the solid pump cams in my boxes of spares if you find you need one. Also have a spare two piece.

Very cool of you, thanks.

[Ruffi]

Thinking that Comp sent the wrong cam gear with this kit...it sure is not for a two piece eccentric.

Spoke with Comp Cams...the 7138 set-up is NOT designed for a two-piece eccentric. Comp Cams will update their documentation to reflect that a one piece is required.