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Timbo's '64FL Panhead Part 3, Engine

(Hard ride back from Hell) But the Engine Rebuild Was a Breeze

By the Tail Gunner with photos by Colleen and images courtesy of the Bob T. collection
4/29/2013


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Barrels before paint was removed.
Barrels before paint was removed.



After the engine was removed from the frame, I mounted it on an engine stand and clamped it to a work mate. This worked perfect, as I have limited working space due to all my daunting, ongoing projects.
 
Engine stand mounted on my work mate.
Engine stand mounted on my work mate.





I got lucky with this engine, as I later found out it had recently been rebuilt and had just .010 over in the bore. However, the rocker covers were both leaking and the front head gasket blew. This was a perfect time to for a complete top end job. I planned to replace all the old leaking OEM gaskets with state of the art new gaskets and seals, and check all the tolerances, while looking for any potential problems.
Top end removed and gear drive exposed.
Top end removed and gear drive exposed.




Tear down was straight forward, first I removed the carburetor, followed by the oil pump, gear drive housing, push rods, tappet blocks, rocker covers, heads and barrels. After the barrels have been removed, place a couple of shop towels around the connecting rods to keep debris from falling into the crankcase.

All gasket material removed and ready for reassembly.
All gasket material removed and ready for reassembly.




I carefully cleaned all old gasket material from all the mounting surfaces. I ended up using razor blades and plastic scrapers. Be careful not to gouge any mating surfaces as you scrap. Any abrasion could create a leak if the gouge is deep enough.

I also rebuilt the generator at this time, which included new brushes and a new paint job.
 


The 6V armature removed from generator.
The 6V armature removed from generator.

 
You can follow the generator instructions in the manual. It's extensive and takes patience, but not overwhelming. I just hope it works, as a new costs around $400! Ouch! I also found "Rene "at National Starter in Lancaster, California. He Put the 6v through its paces to make sure we have a strong working unit, Thanks Rene!! The old mechanical voltage regulator was replaced with a new solid state unit and the OEM dual point circuit breaker was replaced with a state-of-the-art electronic dual contact unit from Quick Start 2000.

Quick Start 2000 electronic duel circuit breaker.
Quick Start 2000 electronic duel circuit breaker.




Ed from Quick Start custom builds electronic circuit breakers specifically for vintage motorcycles, and he spilled a wealth of knowledge, always willing to help in any way he can, yea ED!!!!

Important note: Before restarting the bike, you need to flash the generator polarity. It's simple, run a jumper from the positive battery pole to the term marked -A- on the generator, touch it for a second, and the polarity will be corrected.
 
Since the engine had been recently rebuilt, I took all the measurements for the fly wheel and connecting rods for clearance as specified in the manual, just to make sure all was within limits, and it's right on, how lucky can I get?
 
 

Follow the Manual for limitations.
Follow the Manual for limitations.




So off to J&P Cycles again to order new rings, wrist pin bushings and all the required seals and gaskets. I also replaced the main drive seal on the left side of the crank case, it had been leaking bad.
Picture of the new main shaft seal installed.
Picture of the new main shaft seal installed.




Rebuilding the oil pump was a simple task, you can get the complete kit from J&P Cycle. The gear case cover was removed and the timing marks were checked for alignment.



Oil pump dismantled, cleaned and ready for new gaskets.
Oil pump dismantled, cleaned and ready for new gaskets.




With the gear case open, you can remove and clean the oil pump screen.
 
Added a pressure gauge, hope it works.
Added a pressure gauge, hope it works.

 

Gear case with timing marks aligned.
Gear case with timing marks aligned.



I removed the tappet blocks and tappets, cleaned them and miced them to see if they are within tolerance, they are. Be careful when reinstalling the tappets, they need to go in the same position (same hole) they came out of, with the oil passages near the rollers pointing inward (refer to manual). Failing to do this will cause the engine to seize, and we don't need that.

Shot of the Linkert carb. J&P carries complete rebuild kits. Just takes patience, like taking a watch apart.
Shot of the Linkert carb. J&P carries complete rebuild kits. Just takes patience, like taking a watch apart.



View of the cam shaft through tappet block mount.
View of the cam shaft through tappet block mount.



Timbo wanted the barrels to be blonde, so I had them bead blasted to remove the black Bar-B-Q paint someone had put on. In my opinion, they look way better blonde. As far as the heat transfer, I don't think it makes much difference. Most Harley engines of today are blonde, the black is a cosmetic option. I have built aircraft engines for 20 years, and almost all are bare metal cooling fins. I coated the bare metal with clear 1500 degree heat paint, just to make sure they don't rust up on me.

Barrels before paint was removed.
Barrels before paint was removed.



Barrels after paint was removed.
Barrels after paint was removed.

 
We can argue the "black heat dissipation thing" at a later date! For the barrels and heads, they suggest you purchase a special wrench to ease installation and removal. I found a little patience and a standard 9/16 and 5/8 box end wrench and 12-pt. deep socket worked just fine for removing the barrel and head bolts. I was fortunate to have the original manual, a Clymer manual and a cool restoration book sent to me from Bandit.
 






Follow the rebuild information in the manuals and all will go smoothly. This old gal has a Linkert model M-74 brass carburetor, again, all the parts you need can be found at JP Cycle, and the internet has endless parts suppliers. The carb was completely cleaned and rebuilt, with all new jets and gaskets.
 
Shot of the Linkert carb. J&P carries complete rebuild kits. Just takes patience, like taking a watch apart.
Shot of the Linkert carb. J&P carries complete rebuild kits. Just takes patience, like taking a watch apart.

 
I found lots of Linkert carb tuning tips on line, simple too!! They give you needle starting points and adjustment procedures, I probably found no less than a dozen info sites for the many models they made. For the rocker cover gaskets (pans) I used the new neoprene and steel ones from Genuine (J&P Cycle).
New neoprene pan gasket installed.
New neoprene pan gasket installed.




The Pan gaskets I removed where virtually made out of paper. No wonder they leaked! Here's a shot of the new gaskets installed, you can see the thickness!
 
This bike came to me equipped with a narrow belt drive and standard clutch. It may have been a famous SuperMax Belt Drive, and it will probably last forever. Phil Ross, one of the Belt Drive original designers passed a couple of years ago. "What a great guy, and hard rider," Bandit said.
Belt drive soaked in oil. This belt system is a damn good upgrade. It will save on vibration and wear and tear on the old classic. And know one will know it's there.
Belt drive soaked in oil. This belt system is a damn good upgrade. It will save on vibration and wear and tear on the old classic. And know one will know it's there.




Unfortunately when I pulled the primary off, the belt was soaked in oil. No one had ever bothered to shut off the chain oiler. It's controlled by a needle screw on the oil pump. So not only did I shut it off, when I rebuilt the oil pump, I also reengineered the crank breather system so it now is vented to the outside inner primary via a tube and K&N breather.
Crank breather, hope it works. "Sure it will, or run the line back to the rear chain for oiling," said Wrench.
Crank breather, hope it works. "Sure it will, or run the line back to the rear chain for oiling," said Wrench.




The clutch was taken apart and cleaned along with the clutch plates and belt. The plates were measured for wear and the belt was degreased and dried.




Pictures of the clutch disassembled.
Pictures of the clutch disassembled.





So hear it is, the old Pan looks great. She's been timed with the new electronic breakers, the pushrods have been adjusted, and new seals installed, top end rebuilt, new seals and gaskets everywhere, oil pump rebuilt with the addition of a pressure gauge along with the original light switch.
 
Head and rockers before cleaning. Make sure to keep these sets of brass rocker-boxes together with the shafts. Check for galling, and make sure the oil ports are open. Make sure to carefully torque the studs and locking nuts. They can cause daunting problems.
Head and rockers before cleaning. Make sure to keep these sets of brass rocker-boxes together with the shafts. Check for galling, and make sure the oil ports are open. Make sure to carefully torque the studs and locking nuts. They can cause daunting problems.



New rings installed along with the cylinders cleaned and honed. The heads looked really nice, no gunk had built up yet and the valves were lapped just to make sure. I also cleaned out all the oil passages, don't want any debris mucking things up!!

 
 
New set of Hastings rings.
New set of Hastings rings.




At last, the engine is complete for now. Since beginning this article, I have already installed the engine and trans in the frame, another article on the frame will follow soon.


Engine complete, Top end rebuilt, oil pump rebuilt, new ignition, new gasket and seals everywhere.
Engine complete, Top end rebuilt, oil pump rebuilt, new ignition, new gasket and seals everywhere.



I will however give you a sneak peak.
I will however give you a sneak peak.



Tail Gunner out for now!

 
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Reader Comments


The camshaft. Can you say flat tappet. Am I right or wrong?

Nick Taylor
Bakersfield, CA
Friday, March 27, 2015
Editor Response Not much is flat in a Panhead engine. Most tappets are cupped. Maybe I'm missing your question?
--Bandit
I'm loving these article. I'm collecting parts to restore a '63 FLF and have gone the same route with Belt primary and electronic ignition. I am going with 12v system, electronic regulator in the original regulator case, and wondered if Tail Gunner is staying with 6v for a reason.

rigger
brandywine, MD
Wednesday, May 01, 2013
Editor Response I asked him that very question. He said it was the customer's choice. I rebuilt a couple of '48 Pans and always went 12-Volt with belts.
--Bandit

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