Motor problems WL

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Inge
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Motor problems WL

#1

Post by Inge »

Hi guys,

my name is Ingo and I live in Brunswiek, Germany. I own a 1941 WL for nearly 19 years and now, I meet some troubles with the engine. I must admit that I not use the bike the last 10 years. After reassambling the engine runs for 150 miles, the carburator was not perfectly adjusted but nearly ok. Its a M54 carb. But on my last tour the motor starts to make noises like knocking. Driving with advanced firing point was impossible.
Today I removed the magneto to check the firing point but everthing was in line. After a 1 mile trip, both cylinder getting very hot very quick, crankcase and crankcase cover remain cold.

Can anybody give me a suggest what to do or what to check next? Please check the two movies.










Thank you for help
Ingo
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Re: Motor problems WL

#2

Post by 1950Panhead »

Did you remove old gas and fill with new gas?
Does knocking increase when you advance timing?
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Re: Motor problems WL

#3

Post by Inge »

Only new gas, regular 95 octan and I add "lead additive". The firing point should be ok as well. I removed the heads and checked the position of the first cylinder with a caliper, the mark is in inspection hole. I checked the firing point with a multimeter. As I wrote before, the motor was running for 150 miles, starts with the first kick, no matter if cold or warm. The noises came suddenly
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Re: Motor problems WL

#4

Post by 1950Panhead »

Does the mag fire at retard or full advance with timing mark visable in hole ?
Inge
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Re: Motor problems WL

#5

Post by Inge »

1950Panhead wrote:Does the mag fire at retard or full advance with timing mark visable in hole ?
full advance with timing mark in hole, 9/32 inch before top.
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Re: Motor problems WL

#6

Post by Inge »

Hi guys,

by that time I disassambled the motor. The reason for the noises was a worn piston rod bearing. The Piston rod end play (eye) was nearly 2cm-3cm. The crank shaft has been refurbished, pistons and cylinders are new. Now I go ahead and change all bearings and bushings.
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Re: Motor problems WL

#7

Post by Mark44 »

Inge wrote:The reason for the noises was a worn piston rod bearing. The Piston rod end play (eye) was nearly 2cm-3cm.
Wow! That's a huge amount of slop, around 1 inch. You didn't mean 2 mm - 3mm, did you?

I just listened to the videos you posted, and maybe 2 - 3 cm is correct. It sounds like the pistons were hitting the heads. The pistons must have really taken a beating!
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Re: Motor problems WL

#8

Post by Inge »

Mark44 wrote:
Inge wrote:The reason for the noises was a worn piston rod bearing. The Piston rod end play (eye) was nearly 2cm-3cm.
Wow! That's a huge amount of slop, around 1 inch. You didn't mean 2 mm - 3mm, did you?

I just listened to the videos you posted, and maybe 2 - 3 cm is correct. It sounds like the pistons were hitting the heads. The pistons must have really taken a beating!

Yes, probably the pistons hitting the heads. The bearing was worn and broken and the shaft was worn- out as well. Now it´s winter time and I have enough time for a complete overhaul :)


https://www.youtube.com/watch?v=95q1XTvK-sQ


:? :? :? :?
Mark44
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Re: Motor problems WL

#9

Post by Mark44 »

Inge wrote:The reason for the noises was a worn piston rod bearing. The Piston rod end play (eye) was nearly 2cm-3cm.
Inge wrote:Yes, probably the pistons hitting the heads. The bearing was worn and broken and the shaft was worn- out as well. Now it´s winter time and I have enough time for a complete overhaul :)
So you're saying that the piston end of the rod and its pin were that worn, not the lower (crankpin) end? I would think with as much damage as you described, there would have been excessive noise for a long time before the catastrophic failure.
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Re: Motor problems WL

#10

Post by Inge »

Hi guys,

now it’s time to go ahead with the motor. I already bought all bearings, bushings, etc. The crankshaft has been refurbished, cylinder, valves and pistons honed.
Now I decided to change the crank case and I bought one with matching numbers from 41’. Both, the new and the old have pros and cons. My question now is, my old case is a mix 41/48, with the additional drilling’s for the lubrication of valve guides.
Is this modification essential or not?

Thanks Ingo
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Re: Motor problems WL

#11

Post by Inge »

Hi,
I build up a new engine, furtunatly I found a NOS crankcase. I have a question regarding the end left bearing 421-39. It´s already build in and now I wounder if it makes sense to replace it with a modern oil seal kit 421-39S

Image

Wouth it?
Last edited by panhead on Tue May 12, 2020 12:01 pm, edited 1 time in total.
Reason: made picture visible
flatheadDave
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Re: Motor problems WL

#12

Post by flatheadDave »

Inge wrote: Tue May 12, 2020 11:54 am Hi,
I build up a new engine, furtunatly I found a NOS crankcase. I have a question regarding the end left bearing 421-39. It´s already build in and now I wounder if it makes sense to replace it with a modern oil seal kit 421-39S

Image

Wouth it?
I think so. Ive done this replacement a few times.

The seal is easy to replace, even with the engine installed in the bike..

After you loosen the rear wheel, transmission, remove the clutch, floor board, and the chains and sprocket you'll be ready to do the replacement.

With the motor sprocket off, pry/pull off the retaining ring and the old style "seal". The old pieces will pull right out easily from the left side case, exposing the roller bearings.

When installing the new style seal, make sure you grease the new rubber seal, so on initial start up, the motor side crank shaft doest eat up the new seal.

Gluck!
-Dave
Inge
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Re: Motor problems WL

#13

Post by Inge »

Hi Dave,

many thanks for your instruction. Ill change the seal when I rebuild my engine (engine is now on the workbench).
Inge
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Re: Motor problems WL

#14

Post by Inge »

Hi,

I am not sure, should I use the old gears or should I replace? The shaft is new. Too much clearance?



Thank you!
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Re: Motor problems WL

#15

Post by RooDog »

Thank You for that video.
I had this same problem with my 1950 FL Panhead. The back lash was as much as shown in the video, I luckily found a "Close Fit" pinion gear, #24010-51, that was a light hammer drive into position, and all my noises went away. Hmmm, must be why the MoCo went to a keyed tapered shaft & gear setup in 1954.....
Do find some way to get rid of that slop, if not, you'll wish you had.....
....RooDog....
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