51 FL Base Gasket replacement

[Froger]

Yes, top end oil drains through the hole in the cylinder wall. That is the standard set-up for pans & shovels '53 - '84. The drilling just dead ends at the base gasket.

Jim

Thanks Jim I sort of thought that was the procedure , but what about the feed to top end as all the the feed's are blocked with the gaskets for what looks to be a feed in the cases on the right side .. Am I right to think the oil is pushed up through the push rods lifters ?

[JBinNC]

Stock pans with the heads like yours feed top end oil through the holes in the cylinders on the right side. The last three years, the top end oil was fed through outside oil lines, similar to the shovelheads. It is possible to feed top end oil through the pushrods on a pan, but that requires a bunch of specialized parts, essentially converting to evo style tappets. From the pics, you seem to have the standard pan valve train parts. So, the rocker arms MUST be oiled through the cylinders. If the motor has been run for any time with the cylinder oil passages blocked off, the rocker arms and pillow blocks are probably pretty much junk. Let me say that there are some pitfalls in dealing with the pan oiling system, and I have seen several motors with undue wear and damage because the builder did not understand the oiling system, or just did not care.

Jim

[TriNortchopz]

Flo says they have a solution to improve top end oiling:

"...The problem is a poorly designed top-end oiling system, resulting in lack of lubrication that drastically shortens the life of critical components.

In stock Panhead engines, oil is routed through a passageway in the head that is only an eighth of an inch away from the combustion chamber. By the time it reaches the moving parts the oil is more than 100 degrees hotter than the oil in the tank, and its viscosity is reduced to less than 10-weight.

Inadequate lubrication by this thin, hot oil causes excessive wear at the rocker arm, valve stem, and valve guide...

we have researched this problem thoroughly and developed an external oiling system that we guarantee will double the life expectancy of your Pan or Shovel’s rockers, valves, and guides. Plus, your engine will run smoother and cooler.

How big a difference does our Top End Oiler Kit make? The oil temperature in the tank will be reduced by 50 degrees in Panheads and 30 degrees in Shovelheads...

Not only does the final result work great, it looks great, too."

https://www.floheadworks.com/Products/Top%20End%20Oiler%20Kit.htm

[JBinNC]

Flo says they have a solution to improve top end oiling:

"...The problem is a poorly designed top-end oiling system, resulting in lack of lubrication that drastically shortens the life of critical components.

In stock Panhead engines, oil is routed through a passageway in the head that is only an eighth of an inch away from the combustion chamber. By the time it reaches the moving parts the oil is more than 100 degrees hotter than the oil in the tank, and its viscosity is reduced to less than 10-weight.

Inadequate lubrication by this thin, hot oil causes excessive wear at the rocker arm, valve stem, and valve guide...

we have researched this problem thoroughly and developed an external oiling system that we guarantee will double the life expectancy of your Pan or Shovel’s rockers, valves, and guides. Plus, your engine will run smoother and cooler.

How big a difference does our Top End Oiler Kit make? The oil temperature in the tank will be reduced by 50 degrees in Panheads and 30 degrees in Shovelheads...

Not only does the final result work great, it looks great, too."

[ATTACH=CONFIG]110422[/ATTACH]

https://www.floheadworks.com/Product...iler%20Kit.htm

Like so many things in the H-D aftermarket, a solution in search of a problem. Functions to separate you from your money.

Jim

[Froger]

Thank's TriNortchopz interesting read ..

[Froger]

Stock pans with the heads like yours feed top end oil through the holes in the cylinders on the right side. The last three years, the top end oil was fed through outside oil lines, similar to the shovelheads. It is possible to feed top end oil through the pushrods on a pan, but that requires a bunch of specialized parts, essentially converting to evo style tappets. From the pics, you seem to have the standard pan valve train parts. So, the rocker arms MUST be oiled through the cylinders. If the motor has been run for any time with the cylinder oil passages blocked off, the rocker arms and pillow blocks are probably pretty much junk. Let me say that there are some pitfalls in dealing with the pan oiling system, and I have seen several motors with undue wear and damage because the builder did not understand the oiling system, or just did not care.

Jim

Thanks for your reply Jim .. I have bought new Cometic base gaskets here in Australia , I have bought 2 sizes as Not knowing what I have ..


As for the plates that didn't have the holes on the right side for oil Gallery's to the top end either I'll drill out to match the gallery holes in the block and use the old gaskets as a guide ..

I also pulled the lifter blocks out and the cam chest cover off yesterday to take a look and it appears to be running solid's and a H cam , would there be any benefit to putting a J cam in ?

I also the checked the rockers again in the head's and they appeared to be in good condition still , I'm at a loss as to how they were being oiled as there was oil up there when I pulled the covers off , but we'll leave that as mystery!

[JBinNC]

I like the Andrews J grind as a readily available more-or-less stock replacement. Watch out for worn journals on old H cams, simply because they are getting so old. Journal wear is often overlooked. For the bushings, the journals will run at .810 - .811, quite happily. If you have a roller bearing for an inner cam bearing, .8115 is probably the minimum you can get away with.

Jim

[TriNortchopz]

did some reading on the journal sizing/inner cam bushing/needle bearing...
that inner cam bearing change in '58 from the bronze bushing to the Torrington needle bearing is interesting, as it is 0.002" smaller - maybe just due to what was available. It looks like the same needle bearing is used for the '58 - '84 engines; HD #9058.

https://aaok.com/index.php/motor-parts-panhead/panhead-cam-chest-parts/inner-cam-bearing-for-crankcase-1958-1984.html

[JBinNC]

did some reading on the journal sizing/inner cam bushing/needle bearing...
that inner cam bearing change in '58 from the bronze bushing to the Torrington needle bearing is interesting, as it is 0.002" smaller - maybe just due to what was available. It looks like the same needle bearing is used for the '58 - '84 engines; HD #9058.

https://aaok.com/index.php/motor-parts-panhead/panhead-cam-chest-parts/inner-cam-bearing-for-crankcase-1958-1984.html

Sifton (the old, REAL Sifton, not the junk Sifton of today) would supply generator cams with either inner journal size on request. Yes, today you get one-size-does-not-fit-all generator cams with the needle bearing size journal. But that is easily dealt with, as most inner bushings with beaucoup miles on them are already worn to a suitable size. If building a motor from scratch, ream a new inner bushing with a 13/16 + .001 reamer (.8135) which are standard stocking items, and you are golden.

In answer to the needle bearing ID, an .8125 listed bearing is meant to run on a nominal 13/16 shaft. I really don't know the EXACT clearance required, but a .8120 journal would run fine, and a journal at .8115 is getting loose.

The reason I mentioned cam journal wear is that inner cam journals that run in bushings exhibit more wear, probably why H-D switched to a bearing. This is particularly a problem with early XL cams where those motors were fitted with bushings.

Jim

Last edited by JBinNC; 04-08-2023, 8:53 AM.

[JBinNC]

Koyo, the bearing mfg., lists the shaft size for the B-138, which is the inner cam bearing, as .8120 - .8125. (These were originally Torrington bearings, but Koyo bought Torrington 15 or 20 years ago. The bearings are still made in the USA, probably in the same plants.)

Jim

[TriNortchopz]

Thanks Jim; do you prefer the inner bushing or a needle bearing?

You mention wear on the old H cam journals - any thoughts on the new S&S H cam as stock replacement?

S&S Cycle H-Grind Cam For Harley Panhead 1948-1957
H-Grind Cam Info:

OEM-spec replacement hydraulic cam with unique front and rear timing specs
Dead-on reproduction of the stock cams used in Big Twins
Perfect for repair and restoration of 74" and 80" engines
Intake open front/rear 0°/20°
Intake close front/rear 40°/33°
Exhaust open front/rear 53°/53°
Exhaust close front/rear 12°/12°
Intake duration front/rear 220°/233°
Exhaust duration front/rear 245°/245°
Lift front/rear .389"/.391"

https://www.revzilla.com/motorcycle/ss-h-grind-camshaft-for-harley-panhead-1948-1957?sku_id=959735

Andrews J:

10.8mm = 0.425" .... 3.91 mm = 0.154"
they note this:
In 1948–69 Big Twin motors, the clearance between the front exhaust lobe and the ignition drive gear must be checked and modified as required. In most cases the ignition drive gear must be turned down approximately 7 mm...(0.276)"

https://www.wwag.com/en/andrews-cams-panhead-and-early-shovelhead-j-grind#0

is the turning down the drive gear a common thing with cam swaps?

[Froger]

I'm back I've been in Hospital have a couple of Broken Ribs , so not fully into it at the moment .. I took some picks of the Cometic new gaskets turned out to be standard that fitted but one problem , the oil gallery holes in the block to cylinder base hole they are not fully lined up there is a third of the gallery hole hole covered by the gasket !
I don't want to modify the gasket hole as they have that tiny bead rubber in them ,or do I modify and use some decent gasket sealer??
Or do I use paper gaskets as it would be easier modify the oil holes and use some sort of decent sealer on them ??

I have bought a whole James engine gasket kit .. Do I use decent gasket sealer for all of them ,such as Locktite , Permatex or is there something better ??
pic with gasket over oil hole

Same again different angle

Oil hole in block

oil hole in block

[JBinNC]

I run into that a lot. It seems the front base gaskets are beyond the makers' capabilities to produce accurately. Just modify the gaskets (and plates if needed). You can use a round jeweler's file or small chainsaw file, or scrape them with a sharp knife, Exacto, etc.

Your pics show the hole in the case in an odd place. the other alternative would be to chamfer the hole on one side to align it with the gaskets. Again, scraping with a sharp knife, and of course capturing any chips, would do it.

Jim

[Froger]

Thanks Jim .. I appreciate your input and knowledge ..

[TriNortchopz]

...Do I use decent gasket sealer for all of them ,such as Locktite , Permatex or is there something better ??

heard of Hylomar products?

Hylomar manufactures a wide range of high performance sealants and adhesives used by some of the leading OEM’s in the world of automotive, aerospace, white goods, power generation/distribution, electronics/photonics and general engineering.
Hylomar Aerograde, Aerograde Ultra and Advanced Formulation are specified by various aero-engine manufacturers; including Rolls-Royce and Pratt & Whitney.
Hylomar Aerograde is also specified by NATO."

https://hylomar.com/en/