431 mel chris craft - distributors & starters

marcrbeaudry said:

Hoping to tap into some old Chris knowledge -
i'm working on a pair of 431's which were said to be rebuilt but never commissioned and then mothballed.
Are these 431s the old ChrisCraft built engines?

Many years later now - should the ports side - reverse engine starter spin opposite to the starboard side (normal rotation)
engine ? -working under the premise that there are no stupid questions here...
There are no stupid questions.... only unanswered questions.

In general, the Starboard engine will be the RH Reverse rotation engine, unless fitted to V-drives and/or in a flywheel facing forward installation.
None-the-less..... yes, your RH Reverse rotation engine's starter motor will need to rotate opposite of the other engine's starter motor.


I'm entirely and competely aware these are obscure and relatively rare engines and perhaps there are many
better ideas for better engine alternatives -
I would think so!
ChrisCraft did some rather goofy and unorthodox things back then.

but this is where I am at present and my intent is to spend the time to finish commissioning them as they do appear to have been rebuilt .

Distributor - should the port side- reverse rotation engine spin opposite to the starboard engine ?
Mark, in general, the distributor drives the oil pump.
Since the RH Rev rotation engine's oil pump will generally turn in the standard direction, the the distributor rotation remains the same between each engine.
If so, you will simply begin with #1 cylinder spark plug cable in the #1 cap location.
You will then install the next-in-line-to-fire cylinder spark plug cable into the cap and in the standard rotor/shaft direction.
You will then continue right down the Reverse engine firing order.
If you can post the Std 431 LH engine firing order, I can help you with the RH Rev rotation spark plug cable locations.

SBC example:
SBC distributor rotates CW when viewed from above.
Std LH rotation engine firing order is 1,8,4,3,6,5,7,2
RH Reverse rotation engine begins with #1 followed by 2,7,5,6,3,4,8
Each is indexed in a CW orientation.

Starboard is running ok - port side is giving me grief -

Can anyone recommend some parts sources for 431 starters (port side - reverse rotation )
Perhaps check with Arco, Sierra, Delco or one of the other major players.
You may also want to contact Richard @ SeaManufacturing on the east coast. He may be your best bet!

Do yourself a favor, and DO NOT use the old Bendix style starter motors.
Instead, try to find the HTGR/PMGR motors.

Also - Mallory YD distributor parts, assembly drawings ? is the drive pinion opposite on the two enines to achieve
rotataion correction ?
Again, we would need to know how the oil pump is driven.
In most cases, the oil pump rotation remains the same between both RH and LH engines.
However, I do not know what ChrisCraft did on these engines.

exhaust manifolds - i take it are hen's teeth - are there sources for replacements for these ?
You would need to contact Barr, Osco, GLM, HGE, or even Sierra.
If you have the space above, I would suggest going with the center-rise style, and then plumb them in a more modern-day fashion.

thanks for your input , adivce and even bad jokes
kind regards

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