In search of gaskets for a 1978 CB750A Hondamatic.

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Hello,
We are in the process of resurrecting a 1978 CB750A "Hondamatic". Although we have found some of the gaskets on eBay etc. we were hopeful to locate the main gaskets we need with one supplier. The gaskets we need are: Oil Pan Gasket (OEM #11398-393-000 a.k.a. #11398-425-306); Stator/Alternator Gasket (OEM #11397-300-306 a.k.a. #11397-300-040 OR #11397-393-000); Left Side Crankcase Cover Gasket (OEM #11396-393-000) We do not necessarily need Honda OEM parts. The OEM #'s are provided as a hopeful reference. One other gasket/seal that we would like to replace (if it exists) is the gasket or seal that would be on the torque converter - right side of the engine. We have not found any reference that suggests a gasket was used there which suggests the use of a case sealant. Any assistance will be sincerely appreciated.
Thank you and Make It A Great Day!!!
Respectfully,
Wayne K
 
Hello,
Thanks for the input. We have since located and have purchased the Oil Pan and Stator/Alternator Cover gaskets. Still in search of the Left Side Crankcase gasket. We use Partzilla on occasion and have checked with Vintage CB750 ... NA from either of them. We have heard of RevZilla as well as Dime City, but have not checked with them. We will now though! Thanks again and as always ... Make It A Great Day!!! Respectfully, Wayne K
 
For the future... many of our aluminum cover gaskets are very easy to make using the gasket paper sold at auto parts stores. They last, so long as you make sure to keep them whole, just like any other gasket. I clean off the aluminum where the old gasket was, generally with a razor blade. Then dampen the entire contact edge of my part with clean motor oil, and lay it down on the gasket paper for a minute, pressing it down firmly. I double check my impression against the part, and if it's all correct, cut it out.

This certainly works for the dynamo cover, clutch cover, gear shift cover (mission cover, whatever) and valve cover. Obviously head gaskets are a different story, but yes, they are sturdy. I wouldn't consider this jury-rigging or redneck fixit, many gaskets can totally be made by hand.
 
Hello,
Thank you for the input! We have a rather generic/basic CB750 shop manual, but no, we do not have a shop manual that is specific for the CB750A, so I'll have to check that out! Thankfully since my last post here, for this particular project anyway. we have been able to locate and subsequently acquire all of the gaskets and seals we needed to get the engine on this bike resurrected. I personally have made my share of gaskets for other applications in the past. Nevertheless, I like and will need to remember the technique you are suggesting regarding using a bit of oil on the contact edge of the part in need of a gasket replacement. I have not used that idea before. Cool stuff! Thanks again for sharing.
In the meantime and as always ... Make It A Great Day!!!
Respectfully,
Wayne K
 
I have an Official Honda CB750A 1976-1978 paper Shop Manual for sale. Printed 12/1977. It has some light water stains on the first 5 pages, but otherwise it's like new.
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