[barab63]

I'm starting the engine assembly of a 1972 CB350K4 stock rebuild. All the engine components have been cleaned with Gunk degreaser and/or Simple Green, rinsed in water, dried, and the steel parts lightly coated with WD-40. In some web videos they strongly advise using a product called "Varsol" to clean the engine's upper and lower mating surfaces before applying the sealant (Honda Bond, Three Bond, what have you). It seems Varsol is difficult to get in the U.S., so I'm wondering if there is something else that is just as effective for this purpose? One pic attached of the surface in question.Thanks. John

 

[pemdoc65]

I use acetone for cleaning the sealing surfaces, then Hondabond.

 

[ancientdad]

I suppose it helps to do the extra cleaning, and maybe call me lazy in this regard if you will, but once the parts are washed I just simply wipe the surfaces with a clean rag and put the Hondabond on. Honda's precision in their horizontally-split crankcases (and even their vertically-split as well, like singles) has been more than good enough to seal with any good sealer and a decently clean surface. Before there was Hondabond available to the public, at the Honda shops I worked at we used GE silicone sealer (in proper proportions, not spooged all over like some RTV jobs we've seen) and it worked just fine then too. I've never had a leak from the lower end on any horizontally-split Honda engine

 

[Bill H]

I lightly draw file with a fine file to check for high spots then clean the surface with alcohol. Acetone is fine but I use alcohol to clean parts before powder coating so its what I have on hand.

Bill

 

[barab63]

Thanks, guys. I guess the extra step with acetone won't hurt. Have a nice holiday. John

 

[TOOLS1]

I clean the surfaces with brake clean before assembling them. If any oil gets on them during the installation of parts I just wipe it off with a paper towel before applying the whateverbond.
TOOLS

 

[barab63]

Thanks, Tools1

 

[barab63]

pemdoc65

Which Hondabond Is better for this application - regular (40 F to 300 F) or high temp (75 F to 600 F)? John

 

[pemdoc65]

I have only used the regular version of Hondabond, and have had no issues with it. I haven't tried the high temp.

 

[ancientdad]

^^^yeah, I don't think the high temp version is necessary for the crankcase halves, I used the standard version too

 

[barab63]

Thank you