[modot66]

i was giving my buddy my old cams and upon installation of the cam chest it seemed to not seat by hand with about 1/4" gap to seat. we pulled it out, checked and double checked all o-rings, bolts, etc, and verified there was nothing hanging up. it seemed like it just wasn't quite aligned perfectly. so we SUPER SLOWLY and SUPER GENTLY starting torquing in the tightening pattern and then it went POP and seated.

we rotated everything and it turned smooth. it sounded like it just wasn't going in straight enough then at the end adjusted itself. it didn't sound like something broke it sounded more like it wasn't aligned. we also made sure to clean and chase al threads and bolts before install. in the end all bolts torqued to spec and it seems fine. def had me a little worried though.

anyone else ever had this happen? something to worry about?

 

[ironmark]

The cam plate aliens on 2 dowel pins and according to the service manual you should tap the cam plate with a rubber mallet to seat the cam plate on the dowel pins.
You either didn't seat the cam plate or you may have pulled the oil pump out a little when removing the cam plate and the oil pump had to be re-seated in the cam chest.
Did you rotate the engine when tightening down the oil pump to make sure it is aliened??

 

[modot66]

Yeah we checked dowel pins and aligned oil pump but I guess maybe not enough? Everything seemed fine after install and rotated freely. I didn't tap it down so it's possible the plate was just seating on the dowels. I was just curious if anyone else encountered this. If the oil pump was off alignment which caused the tough fit but now spins freely should we pull it again? Or was it just seating and can be considered good? From my knowledge of oil pumps I think it is fine, but I don't have as much experience as others on this board.

 

[ironmark]

If you got good oil psi then you should be good.
The service manual wants you to alien the oil pump every time you remove the cam plate by rotating the engine while tightening the oil pump to the cam plate, the instructions are in the HD service manual for your year/model bike.
The oil pumps inside gerotor gears are on the crankshaft and rotate with the crankshaft but the outer gerotor gears float inside the oil pump housing and are driven by the inner gerotor gears.
Aliening the oil pump assures that the inner and outer gerotor gears mesh properly and seal correctly to insure proper oil flow.

 

[torqu]

Why was the oil pump unbolted from the cam plate? If it was removed Harley, Heartland,& Jims make alignment dowel for the oil pump. I believe they are the same ones used to align the tappet blocks on the Evos.

 

[ironmark]

Why was the oil pump unbolted from the cam plate? If it was removed Harley, Heartland,& Jims make alignment dowel for the oil pump. I believe they are the same ones used to align the tappet blocks on the Evos.

The oil pump should always unbolted from the cam plate upon removal. You could pull the cam plate out with the oil pump on it but installing would be another issue. Making sure the inner gerotor gears get on the crankshaft right and the oil pump seats in the crankcase would be the installation problems
You don't really need the alignment pins and the HD service manual doesn't mention to use alignment pins and the pins are not listed in the specilty tools used in the manual.
Following the instructions in the service manual works just fine and even if you did use alignment pins you would still have to rotate the engine while tightening the oil pump to the cam plate. The purpose of rotating the engine is so that the gerotor gears find their natural center.

 

[modot66]

i didn't remove the oil pump from the cam plate as i thought all you had to do was get it on the crank and spin it around to get it aligned. have i been doing this wrong? i was about to fire it up tomorrow, really don't want to tear it all down again. normally i would say it was just seating on the dowel pins. but now i am starting to freak myself out.

i know on older TC88's it was a different story and there was a procdure to align the oil pump.

 

[torqu]

The oil pump should always unbolted from the cam plate upon removal. You could pull the cam plate out with the oil pump on it but installing would be another issue. Making sure the inner gerotor gears get on the crankshaft right and the oil pump seats in the crankcase would be the installation problems
You don't really need the alignment pins and the HD service manual doesn't mention to use alignment pins and the pins are not listed in the specilty tools used in the manual.
Following the instructions in the service manual works just fine and even if you did use alignment pins you would still have to rotate the engine while tightening the oil pump to the cam plate. The purpose of rotating the engine is so that the gerotor gears find their natural center.[/QUOTE


Then how come on in many videos I've ever seen, they leave the oil pump bolted to the plate. They line up the flats of the pump with the flats of the crank???? S&S videos and Fuel Moto videos. I'm guess those guys are incorrect? IRONMARK, I'm not arguing with you. It just seems like alot of videos and techs are leaving the pump on the plate. I've read the Harley specific instructions. Just not sure why the techs are not doing it this way?]

 

[torqu]

i didn't remove the oil pump from the cam plate as i thought all you had to do was get it on the crank and spin it around to get it aligned. have i been doing this wrong? i was about to fire it up tomorrow, really don't want to tear it all down again. normally i would say it was just seating on the dowel pins. but now i am starting to freak myself out.

i know on older TC88's it was a different story and there was a procdure to align the oil pump.

Are the cam bearings fully seated???

 

[modot66]

they are, yes. i am thinking it must have been just slightly misaligned when popping on the dowel pins. i didn't use a rubber mallet like the manual recommends. so my thinking is the pop was the cam chest seating on the pins.

Are the cam bearings fully seated???

 

[torqu]

Did you get the issue resolved? At this point you may wanna try loosening the bolts like Ironmark mentioned.

 

[hd4cruzin]

I just did a cam install and followed the Fuelmoto and S&S videos and did not remove the oil pump from the cam plate.

Installed everything and started it up. Seems to be okay. The oil pressure is a little higher at idle but normal at cruise.

I'm having it dyno tuned tomorrow. Hope it doesn't blow up.

 

[modot66]

how long did it take for you to get oil pressure? i just ran the starter without the plugs and got no pressure. let it run for almost a minute. i think i am going to have to go back in and check everything again. seems like i am not getting oil pressure. yay.

I just did a cam install and followed the Fuelmoto and S&S videos and did not remove the oil pump from the cam plate.

Installed everything and started it up. Seems to be okay. The oil pressure is a little higher at idle but normal at cruise.

I'm having it dyno tuned tomorrow. Hope it doesn't blow up.

 

[modot66]

Fuuuuuuuggggg!!!!!!!!!!

so pulled my oil pump apart. that POP was the narrow gerotor set that sits against the cam plate.

now i'm freaked out because i can't find the missing piece. i ran the bike without plugs for about 50 seconds and stopped when i didn't get oil pressure.

i sure would feel better if i could find the missing metal.

WORD TO THE WISE...ALIGN YOUR OIL PUMP WHEN DOING CAMS

 

[Desertwndrr]

There is no missing piece. That rotor does not fit tight all the way around. It sits offset in the teeth and rotate through them as the shaft turns. Thats how it pumps up the oil. Take it out and fit it together and you will se that it is smaller in diameter than the wide geroter. There is one less gear on the small geroter than the large geroter.

 

[kouack]

There is no missing piece. That rotor does not fit tight all the way around. It sits offset in the teeth and rotate through them as the shaft turns. Thats how it pumps up the oil. Take it out and fit it together and you will se that it is smaller in diameter than the wide geroter. There is one less gear on the small geroter than the large geroter.

have a better look at the pictures missing a thooth and i can see 3 cracks also,

 

[modot66]

yeah i finally got my thinking cap on and came to the same conclusion that it just spread apart. no missing teeth. def was a scary 30 minutes looking for pieces of metal and not seeing anything. i'm amazed that it broke like that, but at least i didn't run turn the engine over for more than 45-50 seconds. crank, cam plate, and other oil pump components are fine. just ordered the new gerotor and now will have to wait til monday to button it all up again.

lesson learned here for sure. from now on i will always make sure to carefully align that oil pump.

 

[Desertwndrr]

have a better look at the pictures missing a thooth and i can see 3 cracks also,

Kouack,
Have you ever had the oil pump pieces in your hand? I think I know what I'm talking about.

Modot66,
I looked around because I thought that I had an extra here, but I came up short. Glad that you got it all figured out. Since you have had the oil pump unbolted from the cam plate go ahead and reinstall it first before the cam plate and make sure that everything lines up on the crankshaft. Then the cam plate (FYI mine went on really tight too). Don't even bother with the screws until both are in place. Roll the rear tire to run the crank around a few times as you lightly tighten the screws, progressively getting them tighter one at a time as you continue to turn the rear tire. That should center it all up nicely.

 

[calgaryglide]

I concur, the inner gerotor has split, expanded, no chunk missing. There may be miniscule flakes or grains of metal, but nothing that the magnet on the drain plug would not pickup.

The cracks are from the expansion forces. After the gerotor split, centrifugal force pushed it into aligning the way it has against the outer gerotor. It is basically a lobe style pump that moves the oil. Lobe pumps are usually used in sewage treatment plants or situations where a slurry needs to be pumped (concrete), not really a liquid but not a solid either. In most lobe pumps the lobes are usually cast out of rubber.

In the case of the twin cam motor a rubber inner gerotor would not last, the durometer of the rubber, no matter how hard, would cause the lobe to fail rapidly compared to steel, that and the rpm of the crank.

Calgaryglide

 

[ironmark]

To alien the oil pump I just put the engine in neutral and hit the starter. Just make sure you pull the spark plugs (which should already be pulled), using the starter to turn the engine over is easier when doing the work by yourself because the starter turns the engine over faster and more consistently then you can if you were turning the rear wheel by hand and tightening the oil pump at the same time. Also when using the starter you will know the oil pump is working because you will see oil coming out of a few holes in the cam plate. You won't lose much oil when using the starter to turn over the engine during the alignment process but is good to have a drain pan in place before starting this procedure.