Injector pump tappet

[akghound]

When I was putting the engine back together after the crank gear challenge I found a flat roller on the injector pump tappet. Ordered one from John but while waiting for it I became restless and decided to fix the one I have.


Used this roller bearing bought locally.


Needed to add spacers as the original was 10mm wide and the new one is 6mm wide.
Drilled the axle hole to 10mm and used a steel bushing for an axle, simply peaned it over and filed it down to fit through the hole in the block.

Wish the focus was better on the pictures .... sorry
Ken Gardner

[veggie]

Interesting....nice repair.
Was the old bearing "open" or was it sealed like the new one that you installed?
Just wondering about splash lubrication. (Or lack of it).

Veggie

[vdubnut62]

Doggone, Ken that's a slick repair. My hats off to you.
Ron

[akghound]

Interesting....nice repair.
Was the old bearing "open" or was it sealed like the new one that you installed?
Just wondering about splash lubrication. (Or lack of it).

Veggie

The old one was just a solid roller not a bearing. That is it in the top picture.
I'm not certain that it can take the constant pounding, but I'll bet it does. So I put it on the end of the cam opposite of the governor just incase it did self-distruct. This way all the parts will be contained within the housing and not fall into the crankcase, timing gears, etc. I'm not certain that it can take the constant pounding, but I'll bet it does.
The cost of not having this engine running during the cold of winter is about $15-$20 a day. I have another tappet on the way but is still has not arrived and I needed to get things going. Thus it became time for another experiment. Nothing ventured nothing gained. It will be interesting to see just how long this "Fix" will last.
Ken Gardner

[veggie]

Roller tappets ! just like the hot rods guys use.
Probably good for a 1.84663% gain in BHP 

veggie

[mobile_bob]

before everyone runs out and changes their cam followers over to a ball brg, head this warning

standard brgs are made to fit into a housing or carrier, they are not meant to carry a load directly
onto the race itself

there are a relatively small number of brgs with extra thick outer races that are called "cam followers"
they are designed for this type of service.

i use lots of each type working on component saws used in roof truss manufacture, they are used
as guide rollers, and a standard brg is only used as an emergency fix while waiting for the proper cam
follower brg to come in.

the standard brgs will always crack/split and fail if they have "any" cyclic pounding load applied to them
the smaller the brg, the thinner the outer race, the weaker and quicker they fail.

until the brg is used in this application successfully for at least a few hundred hours, i would not suggest
others take to using one thinking it is an upgrade.

think about it, if it was a good idea they would be using them now, the brgs are cheap as dirt from china
and india. the economies of scale should illustrate that an off the shelf brg would be far cheaper than a solid
roller that is manufactured in relatively small numbers.

all i am saying is "proceed with caution" a scarred cam lobe is a pain to deal with, all for the want of a proper roller.

bob g

[sailawayrb]

I would concur 100% with you Bob G.  This type of bearing is normally installed in a housing which keeps the races in alignment and which carry the load.  I would be very careful, inspect at first opportunity (to get a sense how this bearing is fairing in this unusual application), and consider replacing with OEM part at the earliest opportunity.

[akghound]

Well Bob ..........
I proved you right. The bearing didn't last but only a couple hours. Not sure when it broke but I have only run the engine about three hours. I took the cover off to find it broken.: : Thankfully I had it on the side opposite of the timing gear.
Thank You for giving me a "Heads Up". Because you did, the cam lobe was saved from damage.
Guys like you keep guys like me out of trouble ..... sometimes
Ken Gardner

[mobile_bob]

well, i am just glad you caught it before something really ugly happened

good thing you kept an eye on it and had it placed in a position to contain the bits.

good catch!

bob g

[BruceM]

Bob saved the day on this one-  the bearing fix looked just dandy to me, too.
All hail Bob G!

[vdubnut62]

Good eye Bob! I thought it was a great idea.
Ron

[cujet]

Hey, don't use that ball bearing, it's going to break 

[oldgit]

How about something like this? Maybe use the rollers from the lifter for replacement. I know I have seen just the roller for sale somewhere on a Harley parts website
http://www.cas4.com/engine/engine-lifter-tappet-roller-jims-01.html