jameslow

iTrader: (1)

Hi guys,

Can I check, for those guys who mod their engine crank shaft, what sealant did you all use to seal up the hole in the crank shaft to make it smooth?

Thanks!

stefan

Arexxon Motorsil D

RayJ

Permatex Red RTV works just fine.

stefan

The problem with the Permatex is, thaqt is is not liquid and you have to smear it in, which will never give you a smooth surface. The Motorsil stuff is what the manufacturers are using. It's liquid and it flows out like a mirror.

RayJ

Stefan....can't find Motorsil D listed anywhere in the US.

jameslow

iTrader: (1)

Btw is it really very useful to seal up the crank shaft? Overall show great improvement to the engine? Bec from what i know, by modding the crank is the area u can get more power than modding the sleeve! Im i right?

Thanks!

stefan

The silicone is only used when you have a drilled / lightened crank. The deal is that you remove weight from the crank ( towards the clutch side) and then you fill the void with the much lighter silicone, to keep the crankcase volume about the same.

To get good, usable power from an engine, you'll have to modify the entire engine, crank timing and all of the sleeve ports, otherwise you'll have a funny running engine.

JetMD

iTrader: (1)

I have used red permatex a few times with great success. It is hard to get perfectly smooth but if you cut a tongue depressor to the right size and use the rounded end, you can get a nice smooth flat ramp out of it. You'll need something to keep the permatex from sticking to the tongue depressor. I use spit but you can also use a soap and water solution. Would love to know where to find the liquid stuff stefan is talking about in the US. But until then, do what you gotta do.

mxwrench

iTrader: (1)

Threebond 1211 is what I use. Flows perfectly smooth. It is white colored.
Only downfall is it takes about 24 hrs to harden fully. Use of heat will speed things up a bit (max 140deg f.)

Many US modifiers are using this stuff.

BK

JetMD

iTrader: (1)

That stuff looks great. I think i'll give it a try. Thanks!