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| | | | Joined: Mar 2009 Posts: 124 'Bolter | | 'Bolter Joined: Mar 2009 Posts: 124 | i've got my transmission out because i pulled and rebuilt the motor. i'm thinking of rebuilding the tranny.
one or twice when i was driving down a steep hill and used the engine rpms to slow me down it popped out of gear. also, it was noisey. i have heard that the noise is par for the coarse with these transmissions. but i thought i would take the oportunity to replace any worn parts if it was not going to be a real big hassel.
i saw a website where i guy rebuilt an sm420 with nothing but a gear puller, a hammer and a punch. have any of you folks pulled off a sm420 rebuild without a press of some kind?
| | | | | Joined: Jan 2008 Posts: 4,961 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,961 | I think it would be difficult to replace the bearing on the input shaft without a press. Also, if you are going to replace countershaft parts you would need a press. Quite often a perfectly good transmission will jump out of gear when the clutch housing is warped. I always check a housing with a dial indicator. | | | | | Joined: Sep 2007 Posts: 393 'Bolter | | 'Bolter Joined: Sep 2007 Posts: 393 | This is from the Novak Conversions website: We suggest the rebuilder have access to a set of snap ring pliers, and a small arbor press, in addition to standard shop tools.
It's a small world, but I wouldn't want to paint it.
| | | | | Joined: Mar 2009 Posts: 124 'Bolter | | 'Bolter Joined: Mar 2009 Posts: 124 | ok.
i started pulling the tranny apart with the tools i had. the bearings on each side of the input shaft have quite a bit of play. so i guess i'll try and tap them on with the tools i have. if that doesnt work i'll borrow or buy a press.
the sycros and gears look good. | | | | | Joined: May 2007 Posts: 41 Wrench Fetcher | | Wrench Fetcher Joined: May 2007 Posts: 41 | About 5 years ago I had the pleasure of watching a tranny guy disassemble my sm420 in about 30 minutes with a couple of wrenches and basically and impact gun with either an extension on the end. That thing made very easy work of removing all the gears and syncrhonizers. I didn't think it was going to be that easy.
I didn't see the reassembly but he had it back to me the next day. He had to get some parts in from a local supplier and I didn't want to wait.
54Monster | | | | | Joined: Oct 2006 Posts: 9,671 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 9,671 | And if you wathed him dissasemble the SM420 in 30min. how did did he deal with removing the "spacer" so he could remove the countershaft and what did he use to replace the "spacer" with??? http://www.pbase.com/dennygraham/image/137384964 Denny Graham Sandwich, IL
Denny G
Sandwich, IL
| | | | | Joined: Aug 2012 Posts: 338 Shop Shark | | Shop Shark Joined: Aug 2012 Posts: 338 | So my SM420 was apart when I got it. The spacer is not at all damaged and the countershaft is out. I want to replace that bearing behind the spacer anyway.
not sure how they got that spacer out.
Now the spacer by no means is tight like it should be - so that will present an issue | | |
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