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Discussion Starter #1
OK installation of these "Rod needle Bearings" is the only thing about rebuilding the DF (10324) that makes me dodgey because I've never done it. Manual on line (lawnboy) is unclear. EVerything else seems pretty straight forward.

Anyone have an old link with pics or can do a step by step walk through (with pics) about how to do it so I don't chase needle bearings all over the place and get it done right the FIRST time I do it?

I figure if I am going to rip it all apart I might as well go with a slight hone, piston, rings, rod bearings and seals. I have rebuilt the carb, self propel and everything else. Lesson learn-Pay $100 for a mower-sink $100 into it but have a new 2 stroke 6.5 HP DF.

Tips? Suggestions?
Thanks. I want to
 

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Discussion Starter #3
I just use grease to hold them in place while assembling. That's on the F's, I'm assuming the DF has loose conrod to crank bearing like that.
So you use like a #2 bearing grease on the crank and individually stick them on or lap the paper over and the grease will pull them off the paper backing? Am I conceptually on the right track? (Part #5 in diagram)

For the rebuild I am replacing part numbers:
6:2
6:1
9
4
5
11:1
11
12


Should I also replace the part ID #1 (Liner Assemblies)-#15 and #10 (snap rings) while I am at it? Do they wear or can I should I re-use these?

 

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Discussion Starter #5

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Discussion Starter #7
Sucks you have to buy the whole piston assembly on the DF's. Does it come with bearing liners? #1

Looks like a pretty good rebuild and procedure to me. Ball or shoe hone?
No the piston assembly comes with the piston and rings. $34.00 or just the rings $31.00 so might as well get the slug too. The bearing liners are like $18 for both !!

I was thinking of using the shoe hone..
http://www.lawnmowerpros.com/Tools/Tools-Rebuild.asp
Part number 32-1704.

I have a ball hone but its way too big. For the money it'd be good to have the shoe hone-although I'd do it VERY VERY lightly as I think the whole cylinder is in good shape. Must be disciplined in not belling the bore by letting the shoes come out past pivot point but for the 20-45 seconds or so I would be honing (deglazing) I think I can manage.
 

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Decesaed (R.I.P.)
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I use a large shoe hone now, because very small shoes hit 2 stroke ports and such. I want to get a ball hone though, this is the one I might get for F's and other similar size bores, seems like a good light grit to just resurface for the new rings. http://cgi.ebay.com/ebaymotors/2-3-8-Engine-Cylinder-FlexHone-Flex-Hone-Hone-320-grit_W0QQcmdZViewItemQQ_trkparmsZQ7c301Q3a0Q7c293Q3a5Q7c294Q3a30QQ_trksidZp4634Q2ec0Q2em14Q2el1262QQhashZitem3c9e03d8d5QQitemZ260349090005QQptZMotorsQ5fAutomotiveQ5fToolsQQsalenotsupported
 

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Discussion Starter #9 (Edited)
I use a large shoe hone now, because very small shoes hit 2 stroke ports and such. I want to get a ball hone though, this is the one I might get for F's and other similar size bores, seems like a good light grit to just resurface for the new rings. http://cgi.ebay.com/ebaymotors/2-3-8-Engine-Cylinder-FlexHone-Flex-Hone-Hone-320-grit_W0QQcmdZViewItemQQ_trkparmsZQ7c301Q3a0Q7c293Q3a5Q7c294Q3a30QQ_trksidZp4634Q2ec0Q2em14Q2el1262QQhashZitem3c9e03d8d5QQitemZ260349090005QQptZMotorsQ5fAutomotiveQ5fToolsQQsalenotsupported
I was actualy looking at a ball but was worried also that the ball would squeeze into 2 stroke ports. Is the one I referenced above pads too small do you think? I kind like the stone hones-how long are your stones on yours?

I know our stroke is only like 1.75" so the whle bore can't be but a few inches longer on the DF with around a 2.5" bore so I can't get too big on the stones.

Do like that ball though...hmmm.
 

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These needle bearings were installed on a F-series rod-to-crank journal.
The skill set is the same. Be patient and you'll get them to go in there.
 

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Castor Freak
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Yup, I had to install some needle bearings on a D-400 connecting rod, I figured out early that they won't stay on dry. I used bearing grease to hold them on, but I've heard that you can even use petroleum grease to hold them on as it doesn't leave as much as a mess as bearing grease and it can burn up easier because of engine heat.
 

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Discussion Starter #13
He's not reinstalling old bearings, he's installing new bearing that are on factory strip with the sticky on them.

I think my hone has 4" shoes. It works pretty good, not much up and down movement. The LB service manual shows using a ball hone.

Pg. 8 https://lookup3.toro.com/ttcGateway/acrobat/manuals/lball60.pdf
Yep..they sure do huh. 5-7 strokes in each direction with the ball. Is the bore on the F's the same as the Duraforces? The DFs have a 2.5" bore. So the tool you showed me may be a bit small. I'll look for a slightly larger one from the same seller.
Thanks!
 

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Discussion Starter #15 (Edited)

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LAWN-BOY-AHOLIC
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Check to make sure the cylinder wall is beveled at the top and bottom of the exhaust port. You don't want a sharp 90 degree edge there as the rings will expand into the port a few thousandth's and wear prematurely. I use a fine cut oval crossection file to put a bevel on this area and touch up all the ports edges after honing. I also like to use a good synthetic oil as a assembly lube because of its resistance to burn off and carbon formation. Good luck!
 

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Discussion Starter #17
Check to make sure the cylinder wall is beveled at the top and bottom of the exhaust port. You don't want a sharp 90 degree edge there as the rings will expand into the port a few thousandth's and wear prematurely. I use a fine cut oval crossection file to put a bevel on this area and touch up all the ports edges after honing. I also like to use a good synthetic oil as a assembly lube because of its resistance to burn off and carbon formation. Good luck!
Do you use a pad type of hone or the ball? I was thinking because of the flexibility of the ball it would actually work the port edges a but smoother than the paddel style- perhaps adding a touch of bevel to these edges as it flexes into the prts a touch.

When you are talking beveling you are simply saying take any hard edge off round them just a touch correct? Is there enough room to get th efile in at the apprpriate angle? It must because you do it can you give me a best way to do it talk through?

I am ordering up the parts tomorrow. SHould be around $90 for everything through RCPW.
 

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I always replace the liners with rebuilds. They wear faster than the needles or crank journal ever would. They are a bit pricey, but worth it to get the clearances back in check. A good quality engine assembly lube works good for replacing used needles.
 

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Discussion Starter #19
I always replace the liners with rebuilds. They wear faster than the needles or crank journal ever would. They are a bit pricey, but worth it to get the clearances back in check. A good quality engine assembly lube works good for replacing used needles.
Thanks I was going to go with new liners. To me those take the worst beating. Are they plastic?
 
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