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Workshop => Engine and Bottom End => Topic started by: JACK SRAW on February 01, 2015, 01:08:09 PM

Title: Case assembly gasket, Assembly of cases
Post by: JACK SRAW on February 01, 2015, 01:08:09 PM
I am assembling the cases and I am using an oem gasket. Should I put Honda bond on it on 1 side or both sides or an anerobic sealant or nothing. It is a 350 BB cylinder with bored cases. Is it best to heat the main bearing up with a heat gun then use all thread thru the motor mount holes to pull together? Looking for the right way the 1st time. Thanks
Title: Case assembly gasket, Assembly of cases
Post by: Pumashine on February 01, 2015, 02:28:04 PM
Is this the 350 motor you got from Carlos at BDT? I am sure he would have told you how to put it together.
Title: Case assembly gasket, Assembly of cases
Post by: udontknowme on February 01, 2015, 02:30:29 PM
if the mating surfaces are in good shape you should be able to use a dry gasket. personally i dont like honda bond. it can make the gasket pushout then you have to take it back apart. try it and see if you like it is the only advice i can say

not sure what your talking about with the bearing. normally you heat the cases in a oven and freeze the bearings and they drop in. thats how i do it anyways. might need the crank tool to pull the cases together.  maybe theres several ways to do it depending which way you want to go
Title: Case assembly gasket, Assembly of cases
Post by: C-Leigh Racing on February 01, 2015, 09:59:07 PM
I have for many years, when installing the main bearings, put the bearing in a cold place & then used a hot air gun to heat the case & normally the bearing will fall right into place. Hot air gun will take around an hour to heat the case enough & by that time the bearing in the fridge will be cold enough as well. Installing the crank into the flywheel side case half, I use the same process, just being careful moving the heat gun to heat the bearing proper & not damage it.

If you have a Hot Rods crank, those are press fit on both sides of the cases, unless you use a clearanced type on main bearing on the clutch side.
The OEM Honda cranks, are slip fit into the clutch side bearing.

As far as sealant, lot dont like the way it looks, but I'll use sealant on any gasket I install. Now if it was a fresh, brand new machined part that a professional German machinest just got done machining, I probably would just use only a gasket & no sealant, but with as old as our 250Rs are & as much as they have been worked on & tweeked, shes gona get a coat of Three Bond 1211 sealant on those gasket.
Using some sealant that dont look good, is better than getting the engine all together, finding an air leak & having to pull it back down to fix it.
Neil
Title: Case assembly gasket, Assembly of cases
Post by: 2ndmoto on February 02, 2015, 12:27:31 AM
I am a big fan of 1211 also. Easier to work with than hondabond. I use just a few dabs, smooth it over to coat the whole gasket. It is a very lite coat. If it squeezes out when you tighten it, then you have used too much.

Best regard
-Jason
Title: Case assembly gasket, Assembly of cases
Post by: udontknowme on February 02, 2015, 12:43:37 AM
i use sealer also. just not hondabond. cant stand that stuff
Title: Case assembly gasket, Assembly of cases
Post by: PNWrider on February 02, 2015, 09:31:47 AM
Quote from: udontknowme;49718
i use sealer also. just not hondabond. cant stand that stuff

What do you use?
Title: Case assembly gasket, Assembly of cases
Post by: Rupp250 on February 02, 2015, 09:43:04 AM
I use 1211 as well. I can't find it locally so I have to order it. But as far as case gaskets go, unless there is a gouge or nick in it, I just use the gasket.