Panhead Knucklehead oil pump

Lubrication System (oil feed pump and scavenger pump, reservoir, filter, and lines)
Post Reply
Paysonpan
Member
Posts: 38
Joined: Wed Apr 24, 2013 2:30 am
Bikes: 63 FLH
55 FL
honda 90
Been thanked: 1 time

Panhead Knucklehead oil pump

#1

Post by Paysonpan »

My 55 Fl mutt Pan is starting and running very well after all of the help from this forum.Motor has been rebuilt to factory specs. How ever it not only sumps it dumps oil. When running, oil flows freely from the breather and upon shut down it leaks most of the oil out of the tank. I replaced both check balls and did my best to look at the seat without removing pump by shining a flash light and viewing with a magnifier . Seat looked shiny so I did not remove to lap. After start up still same leaking. Consulted Palmer book to find out as much info as I could about the pump to see if perhaps I have either one or both springs wrong.In my reading I find that i have a very early 36 to 39 oil pump. I say this as the 2 oil fittings are cast in the pump cover and not threaded in which Palmer notes as being early pump. Only markings I see are a faint 12 stamped on cover. Measured springs and compared to Palmer and was still confused.Also looked on this site at Knuckle Service manual and see that my spring for check valve is same type as by pass valve spring. Called Old Dude to hopefully purchase right springs. After discussion Dude figures i have wrong springs and is sure the springs I have ordered will correct issue. Springs are on the way. I see that the adjustment for by pass valve is "end of adjusting screw 3/8" from outer from edge of valve chamber". So I will adjust accordingly after assembly.
All this being said, if leak is fixed, will my motor be happy and get enough oil with the Knuckle pump? Or should I track down the correct pump of my year Panhead? Or should I purchase a new shovel style S&S pump suitable for my year Panhead? Don't really want the S&S look but if it is the proper solution I am game. Fellow who built the motor urges me to buy S&S. This is by no means a correct machine but 90% of the parts are OEM and the S&S pump would stand out
Much thanks to all of you for your knowledge
RUBONE
Moderator
Senior Member
Posts: 8378
Joined: Sat Nov 15, 2008 4:09 am
Bikes: Multiple H-D, Ducati, BMW, Triumph, BSA,...
Has thanked: 478 times
Been thanked: 2933 times

Re: Panhead Knucklehead oil pump

#2

Post by RUBONE »

Post a picture of your pump. Knucklehead pumps will not supply enough volume of oil to keep hydraulic lifters pumped up if you are using them. They have much thinner gears than a Panhead pump, so consequently they will not return as much oil either. There are also more issues involved than just check balls. If the pump is worn or the gear clearnce is too great it can be an issue. So can pinion bushing fit. But the pump needs to at least meet the needs of the engine and an early pump is not adequate for a Panhead. Panhead pumps are around though. I have a few bodies and pieces extra. A '68 up Shovelhead pump works fine also (where S&S got their design), but depending on the pump a bit of drilling may be necessary. Not so with a stock Panhead pump. Your pump if not damaged is as valuable as a correct Panhead one so a trade is a good possibility.
Robbie
Paysonpan
Member
Posts: 38
Joined: Wed Apr 24, 2013 2:30 am
Bikes: 63 FLH
55 FL
honda 90
Been thanked: 1 time

Re: Panhead Knucklehead oil pump

#3

Post by Paysonpan »

Rubone
Thanks for the prompt reply. My motor has solid lifters.I will have a friend here this week end who is MAC computer savvy and will be able to help me post photos to this site as I have tried and failed.
I have read many of your posts and always appreciate your incite and knowledge. Would you have interest in a possible trade for my pump?
I can take photos and measurements and email to you if so.
If not Robbie perhaps another member might be interested in a trade as I would much rather deal with some one on the forum than try to find a pump that is not junk on Ebay
Paysonpan
Member
Posts: 38
Joined: Wed Apr 24, 2013 2:30 am
Bikes: 63 FLH
55 FL
honda 90
Been thanked: 1 time

Re: Panhead Knucklehead oil pump

#4

Post by Paysonpan »

I was able to trade my early knuckle pump for 2 later pumps for my project. Also got a handful of gears in the deal along with an oem oil pressure sending bit and 2 shafts. Both do have noticeably larger gears. One pump is complete with check balls and springs. The one with springs has an 1/8" diameter tube about 1 inch long coming out of body close to adjusting screw for oiler of primary. I assume this is for a rear chain oiler. In place of the needle screw for adjusting oiler is a small screw. This pump has a number 4 cast above the oil pressure sending hole.
The other pump has number 3 in same location. The shaft size on lower right of pump is smaller in diameter than the pump with number 4.
# 4 is much better condition than #3 so I hope to use it.
I have searched the knowledge base and consulted Palmer as well as looking through my factory service manual attempting to make sure this pump will work for my 55FL. Cant get an absolute answer so I would like members advice prior to ordering new gears, needle valve, clips and keys for shaft. I will order parts from Old Dude unless someone has a better suggestion.
Also,
Do I need to remove pushrods and lifters prior to removal of gear case cover? Knowledge base says yes and not necessary both.
For operation of the rear chain oiler do i run a copper line to the rear chain guard?
I have attempted to attach pics for the first time and I see them under the add files area below save draft preview submit. But when I click preview they do not show. If you guys can not get photos I will email them to any one wishing to help me out
panhead
Site Admin
Senior Member
Posts: 3289
Joined: Mon Jan 01, 2001 12:00 pm
Bikes: 1954 FL
Location: Holland
Has thanked: 108 times
Been thanked: 486 times

Re: Panhead Knucklehead oil pump

#5

Post by panhead »

Email the pics: panheadforum@gmail.com
Paysonpan
Member
Posts: 38
Joined: Wed Apr 24, 2013 2:30 am
Bikes: 63 FLH
55 FL
honda 90
Been thanked: 1 time

Re: Panhead Knucklehead oil pump

#6

Post by Paysonpan »

Panhead
Pics sent via email
Thank you very much for your help
IMG_0001.jpg
IMG_0002.jpg
IMG_0003.jpg
You do not have the required permissions to view the files attached to this post.
Doc37W
Member
Posts: 217
Joined: Wed Jul 29, 2015 4:56 pm
Bikes: '37 W,'41 ULH,'59 FLH Handshift,'69 Fl Handshift w/sidecar,
Has thanked: 2 times
Been thanked: 17 times

Re: Panhead Knucklehead oil pump

#7

Post by Doc37W »

To make it easier to remove the gears within the cam chest, it is best to remove the pushrods. However, you can pull up the two tappets ( the hydraulic lifters in them) in each tappet block, and wrap a rubber band around the two to hold them from falling down onto the cam. No need to remove the tappet blocks. It makes pulling the cam, timer, and pinion gears easier. As to running a line to the rear chain, that tube had just a small rubber hose run around the rear of the transmission to drip on the inside top of the lower chain running back to the rear sprocket, so it would sling oil down on the chain and any extra away from the bike. Other oil pumps had fittings attached to the return line, as it left the oil pump, for a steel line to do the same thing. I believe the oil pump is for a '65 Pan-'66-'67 shovels with the cast inner & outer primarys. Probably the best oil pump for your pan. Run it, unless you going for a 100 point restoration. Doc
Paysonpan
Member
Posts: 38
Joined: Wed Apr 24, 2013 2:30 am
Bikes: 63 FLH
55 FL
honda 90
Been thanked: 1 time

Re: Panhead Knucklehead oil pump

#8

Post by Paysonpan »

I have not been able to work on my Pan for a while due to other commitments
Back at it now and have installed the pump pictured. I cleaned it thoroughly before installing. The check valve seat "looked" ok as did the ball and spring. After putting oil in tank she still leaks like crazy. Not a drip but a shit ton of oil. This is with out even starting the bike.
I ordered a new correct ball and spring from Old Dude as well as new by pass spring and ball. After install she still leaks. Getting frustrated as the the bike has been a long term project and this is my last issue. Would really like to ride!!
I have read all the info in the knowledge base re sumping and oil pump seats. I am reluctant to "tap" a ball with a drift to seat it as the advice seems to mostly say not to do it. I have considered removing the pump and "lapping" but again there is mixed advice about that procedure.
Regarding "burnishing" the seat. Does any one offer this service that any members know of?
I thought of perhaps welding a ball on the end of a drift and using a low speed drill to turn the drift with a bit of pressure to attempt burnishing . Is this a dumb idea?
I had a shovel pump on my 63 pan for years and never had any problems so i know that is a solution . I will go that route only as a last resort because I really want to keep the look of the stock pump
Thanks as always for all of the expert advice guys
RUBONE
Moderator
Senior Member
Posts: 8378
Joined: Sat Nov 15, 2008 4:09 am
Bikes: Multiple H-D, Ducati, BMW, Triumph, BSA,...
Has thanked: 478 times
Been thanked: 2933 times

Re: Panhead Knucklehead oil pump

#9

Post by RUBONE »

Sounds like you have an issue other than the pump. The fact your problem remains with different pumps make me believe the pump isn't the issue. Was the case drilled for an S&S pump at some point? is the pinion bushing fit right? Is the pump drive shaft bushing fit right? breather line to the oil tank? Something else is going on.
nmaineron
Site sponsor
Site sponsor
Senior Member
Posts: 653
Joined: Sun Oct 17, 2010 1:00 am
Bikes: 1995 fxsts,1963 fl project in progress
Location: Patten,maine
Has thanked: 120 times
Been thanked: 98 times

Re: Panhead Knucklehead oil pump

#10

Post by nmaineron »

Is it possible that you have your feed line connected to the pump wrong? I can only think that you have your lines wrong for it to flow as you say. Just for giggles,you could put a really stiff spring in on the check ball and see if it leaks by, only for test not to run!
Paysonpan
Member
Posts: 38
Joined: Wed Apr 24, 2013 2:30 am
Bikes: 63 FLH
55 FL
honda 90
Been thanked: 1 time

Re: Panhead Knucklehead oil pump

#11

Post by Paysonpan »

Any thing is possible with my walnut sized brain.
To clarify... the feed line is the line coming from the bottom of tank corner facing the rear of the bike which I have connected to lowest inlet on the pump. Is this correct?
white1j0
Member
Posts: 256
Joined: Mon Apr 09, 2012 7:38 pm
Bikes: '02 Fatboy, '47 Knuckle, '52Pan
Has thanked: 60 times
Been thanked: 11 times

Re: Panhead Knucklehead oil pump

#12

Post by white1j0 »

Correct
Weedy
Member
Posts: 81
Joined: Thu Aug 18, 2016 1:58 pm
Bikes: 61 pan
Location: Uxbridge ma
Been thanked: 6 times

Re: Panhead Knucklehead oil pump

#13

Post by Weedy »

correct me if I'm wrong but if oil were to leak past the checkball then it would go into crankcase, right? how is it leaking out the breather? while working on my bike over many months last year I had oil seeping past my checkball. but it didn't leak out the breather until I started it. it had filled the crankcase but took several months. it filled it to the point it seeped past the crank seal. so I guess my question is "how is the oil getting to the breather without running and so quickly?". Sorry I don't know enough about the oil system to offer much help but I'm sure there are more knowledgeable people here who can. good luck.
Post Reply

Return to “Lubrication System/Oil pump/Oil filter”