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jeepwm69

Hondamatic Engine clean up and rebuild

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Bought a 2013 Rubicon a year or two ago, along with a regular Foreman with PS.  Paid $600 for the pair.  I rebuilt the Foreman first, and flipped it.  Now I'm tearing into the Rubicon.

 

When I bought this the guy said it ran good, but wouldn't pull, and he suspected the oil pump chain was off.  Yeah yeah, sure buddy.  For once, the seller was honest and correct!

 

These two bikes have gone well for me thus far.  Fixed up and sold the "parts" machine (pictured after I was finished with it) and will use the tan fenders from the "parts" bike on this Rubicon.

 

 

Oil tank and shift motor were removed from the front of the engine when I got it (they're in a box in the shop).  Upon pulling the front cover (two little 8mm bolts gave me fits but I finally found them and removed them) I found no oil filter in the engine (presumably removed by previous owner when he drained the engine and removed the oil tank) and the main drain plug was also removed.

 

I still see a little gunk in the bottom of the cases, and since I don't know the history of this machine, I'm going to tear it down, clean it out, and put it back together again.  Hondamatic spins easily with no noises or drag, so fingers crossed that it's ok ( @Brian Bertram any pointers on checking the Hondamatic?). 

 

Oil pump sprocket also turns ok, so hopefully the chain came off and it will be a simple clean, reassemble with new gaskets/seals, oil pump chain.

 

I know @shadetree had fits getting the clutch off the Rubicon he worked on a while back, so here's my redneck 3 jaw puller set up I used to get the clutch off. 

08PS.JPG

08PS2.JPG

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This one is confusing.  Very clean on the inside compared to what I’m used to seeing.  Meter shows 2k miles.  Rest of the machine is really clean. 
 

Obviously just the oil pump chain jumped off, right?

 

Not so fast.

 

Piston is 92.96, not OEM obviously.  Pretty scored up on one side. 
 

And the coup de grace?  Wrist pin end of the crank is shot.

 

 

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Road hard and put up wet. Those are the best ones, if you get them cheap. After you rebuild everything you know what you have.

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Got it and another for $600, so got it super cheap. 
 

Gotta do top end, crank, timing chain, oil pump chain, seals. 
 

But like you said, then I’ll know what I have.

 

Think I’m going to drop in the 42 tooth 450 Foreman secondary too.  Isn’t that a drop in tiny GR? 7% IIRC @toodeep

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Another question.  The factory timing chain is made my Daido (D.I.D.).  104L, but I can't find any of the other specs on it, nor can I find a catalog of D.I.D. chains to cross reference the specs.

 

Anyone know where I might find specs to cross reference?    I got these specs off of a KMC (chinese) chain listed on ebay that supposedly will fit the Rubicon.  Looks like KMC makes "hotcams" chains for All Balls.

 

Product Details:
-- Condition: 100% Brand New
-- Brand:Unbranded
-- Chain Type: Cam Chain 3*4*104
-- Chain Length: 104 Links
-- Material: Steel Alloy
-- Manufacturer Part Number: 14401-HN2-003
 
-- Pitch: 1/4"(6.35mm)
-- Outer Plate Inner Width: 0.122"/3.05mm(min)
-- Outer Plate Thickness: 0.028"(0.7mm)
-- Inner Plate Thickness: 0.039"/1mm
-- Inner Plate Height: 0.264"/6.7mm
-- Pin Diam: 0.107"/2.72mm
-- Dver-All Width Riv: 0.24"/6.1mm
-- Average Tensile Stength(Pounds): 1320/550kgf

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Yes, the foreman secondary is around that 7% reduction. It's not a lot but gives it that edge in certain situations.

 

I've only used the OEM chains so I have nothing there.

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Any idea who made the "G2" marked piston?  That's a new one for me.  Looks like Namura makes a 1.5 over for this machine so hopefully that will work since it's already 1.0 over.

 

New cylinders for these things are PRICEY!

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One more question.  Safe to assume that the top ends on these are oiled with the same oil pump that drives the Hondamatic, and that when the transmission stopped pulling due to the oil pump chain being off, that it would have killed the top end and rod on this thing?  Just seems weird that it's already had one top end installed and has such damage on such a clean and low mileage machine, unless a prior owner was running/revving it with no oil going to the top end.

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I have no idea on the piston. I got burned years ago on a bunch of bad bore jobs so everything I do is with new cylinders and pistons when they need it.

 

The times I had an oil pump chain fall off I was pushing snow or dropping into a creek and making the 4 wheeler come to an sudden stop. Yes it oil the whole system so if they had a case of the "I don't care" that sure could have been the cause of all the damage.

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7 minutes ago, toodeep said:

I have no idea on the piston. I got burned years ago on a bunch of bad bore jobs so everything I do is with new cylinders and pistons when they need it.

 

The times I had an oil pump chain fall off I was pushing snow or dropping into a creek and making the 4 wheeler come to an sudden stop. Yes it oil the whole system so if they had a case of the "I don't care" that sure could have been the cause of all the damage.

Dang man, I figured you'd be boring cylinders in house!

 

Local Honda shop charged $100 for a bore last time I checked, and that was several years ago.  I have a guy who specializes on old motorcycles do my cylinders.  First couple of batches he only charged me $30 each.  Last batch I picked up were $60.  I knew he was too cheap before so I paid him.  He does good work and $60 these days is still cheap.

 

The trick is, I drop them off in batches, and I don't bug him about them.  The last batch I dropped off was April, and I just got them a couple of weeks ago.  LOL

 

Dang Rubicon cylinders are $400, without the piston/rings/pin!

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We was always just a small mom and pop shop and had another dealer in a bigger town that did excellent work so they always bored stuff for us. The old guy that did it retired and the new ones was a hit and miss on a good job. Now, by the time I send something off to even a known good person the price and time takes away from profits so new cylinders have been my go to. I really don't do enough of them to chance finding someone new anyway. Over the years I did build up a collection of 680 cylinders though. Those 700 SXS would suck in dust when not maintained correctly and wipe them out.

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2 hours ago, toodeep said:

We was always just a small mom and pop shop and had another dealer in a bigger town that did excellent work so they always bored stuff for us. The old guy that did it retired and the new ones was a hit and miss on a good job. Now, by the time I send something off to even a known good person the price and time takes away from profits so new cylinders have been my go to. I really don't do enough of them to chance finding someone new anyway. Over the years I did build up a collection of 680 cylinders though. Those 700 SXS would suck in dust when not maintained correctly and wipe them out.


Thumper big bore kits lol!

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Crank is on its way to Kentucky to visit Vince (along with the crank out of that gorbage 08 500FM).  31 lbs for two cranks, so not a light package!

 

Vesrah rod was a little over $117 with tax, and the part number is VA-1019.  Vince used to charge $125 for a crank rebuild, so puts me at about $250 for a new crank.  A new crank from Honda is about $640, and the Vesrah rod is supposed to be a better rod that Honda used from the factory, so obviously getting a rebuild is preferable all around to getting a new OEM crank.

 

I will update when I get the crank back from Vince.  Given the runaway inflation we've seen I wouldn't be surprised at all if he's had to up his rates a bit.

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Vince is done with my cranks.  Usual super slow work, got them on Tuesday, is finished with them in ONE DAY.

 

He did go up a hair on the price to $135, but that's most likely to cover an increase in shipping costs to get them back to me.  Still super cheap!

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1 hour ago, jeepwm69 said:

Vince is done with my cranks.  Usual super slow work, got them on Tuesday, is finished with them in ONE DAY.

 

He did go up a hair on the price to $135, but that's most likely to cover an increase in shipping costs to get them back to me.  Still super cheap!

just left autozone, spent over a 100 bucks on 2 wiper blades and 6 ft of fuel line. then went to my local honda dealership to pick up a honda battery, 104.xx otd, yep..prices are through the roof right now !!.

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I'd chalk it up some to hunters being in a rush to get their bikes ready ( well for those who don't use theirs year round) up at Lj's they came out of the wood work for routine maintenance...... Oil  changes, new battries, sometime carb cleanings etc etc.... Might not makes that much of a price change .... But LJ  sure likes this time of the season..... With customers trying blow the shop phone up.... 

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Got my new crank bearings in while I was at the inlaws, so ready to reinstall the rebuilt crank and start putting this thing back together.

 

No gaskets on this engine other than a rubber o-ring type seal for the stator cover.

 

I did make sure the swash plate moves easily and smoothly, along with the Hondamatic spinning smoothly and easily.  @Brian Bertram recommended that I NOT tear the Hondamatic down after describing to him what I found. so I'm going to leave it alone.

 

One question I did have that I couldn't find in the FSM.  Should the swash plate be in any particular position when I button everything up and reinstall the angle sensor?  I know the angle sensor has to be clocked to line up with the tab, but I'm not sure if I need to have the swash plate all the way one direction or the other, have it centered, or whether it even matters.  Any ideas @toodeep?

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It doesn't matter as long as it moves (not locked). When you initialize it, it sets the position of it.

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Got the rear crank bearing pressed in, then the crank and balancer installed this morning.  Didn't go any further because I have the 500 footshift case and transmission all over the workbench, and want to get that back together and out of the way before I go further with this Rubicon engine.

 

I did get the stinky carb torn down and soaking in Berrymans this morning as well......

rubicon crank.jpg

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Was warm this morning so I hit the shop early and worked on the Rubicon engine.

 

I got the case halves back together a week or so ago, so this morning I got the cam chain and oil pump chain installed, and then worked on getting in the subtransmission.

 

The oil pump chain is new OEM, and I feel like it should be a little tighter.  I send the attached video to @Brian Bertram and asked if it's supposed to be like that.  If I had to guess, it's correct.

 

The transmission on this thing all goes under the rear cover, and is fairly simple to reinstall.  I'm using a 450 Foreman final shaft gear which is supposed to be a 7% gear reduction.  It's a 42 tooth vs the factory Rubicon 40 tooth gear.

 

I do seem to have misplaced the oil pump screen that goes in the bottom right under the spring loaded arm that hits the shift drum star bit, so I've got to find that or order a new one before I can button up the back cases.

 

Then, I'll probably wait till my cylinder guy finishes my cylinders, so I can get the top end installed with the cam chain before I put the front cover on.  I don't want to button up the front, end up dropping the cam chain down in there, or getting it off the crank teeth, so will just wait and do that after I get the top end reinstalled.

Rubi transmission.jpg

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Already heard back from @Brian Bertram.  He said the oil pump chain is supposed to be like that, which is what I thought, but nice to hear it confirmed by the expert.

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No luck finding the oil screen in my disaster of a shop, so this morning I cleaned up the head and valve cover, replaced a CV boot on an axle, and replaced a leaky front cover on a 500 FM engine I have in the floor of the shop.

 

Basically I got up, and when I couldn't find that oil screen I did busy work since I was already awake.  LOL

 

New screen on the way, but won't be here for a couple of days and a cold front is coming through today so probably won't mess with it again till early next week.

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You have your work cut out for you. I’m right across the bridge from you. It’s been nice all wk until now. Then it’s suppose to get cold this wk end. Might get out and do some squirrel hunting. 

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