Complete Rebuild - EC250

[5valve]

Did you preoil or lube the main cases gasket or did you install it dry?

30hrs after my rebuild, using preoiled gasket, my cases seep gear oil in the upper area, below carb.

I was told to always preoil the gaskets, that seal oil, and haven't had problems till now.


Also, checking prices for seals and bearings, it's insane. I can overhaul whole engine at the cost of $70, shoping locally, as all parts are standard sizes.
Using original parts would also be much cheaper than prices you got, but its probably US EU thing going on.

 

[GGRider01]

The crank's roller bearing, I believe on the clutch side, is about 65 dollars alone when I last checked prices. That was on Amazon, then I checked a local bearing place and it was even higher.

 

[motopsycho87]

As long as everything isn't dry it's all good really, assembly oil, light grease or whatever, it'll burn off once you give it a rev anyway

 

[rubber Jonny]

awesome!!!!!!!!!!!!

 

[RockefellerGG]

Apologies on the late reply, I just saw the question.

I used a very small amount (a couple dabs) of assembly lube, just to help keep the gasket in place. I added no additional sealant. The factory manual does specify use of a lube.

x2 on the crank bearings. They are very pricey. If someone can do a whole engine for $70, I'd be interested to know what type of bearings they used. That is an insanely low price.

 

[Zman]

I have rebuilt about 8 GG engines. I used stock parts for the first one and paid through the nose for the parts. For the next 7, I switched to sourcing them by bearing and seal number. I sourced the bearings by a number of places and spent considerable time getting good prices and in my opinion, if you are using name brand quality bearings and seals you can not get all of them to fully rebuild the bottom end for $70.

 

[RBrider]

RockerfellerGG, thanks for taking the time to post this thread, it's very helpful.
I just tore my '01 XC 200 down for a bad crank bearing and had my old mini laptop sitting right on the workbench so I could use your thread for quick reference.

Yeah, there are some differences, but still, it was very helpful.

Here's a tip for heating the cases when changing bearings (Especially for those of us who have wives that frown on us putting engine cases in the oven)

I fired up the gas grille, spread out a sheet of aluminum foil over the grills and laid the cases on the foil. Heated the cases up to 175-180 F in no time. I checked temp by sticking a meat thermometer in a bolt hole closest to the bearing hole in question.

Meanwhile, the bearings were in a freezer that was at an indicated 8 below 0 F.

The bearings practically fell in place.

RB

 

[5valve]

I hope replying is not jacking the thread too much, but helping to buy cheaper in future is a good investment.

I made a rough estimate of $70. But took a liberty of calling a supplyer today for price quote, since I overhauled mine in december '15, some parts got a tad more expensive since, but I did undershoot a bit, for which I apologize.

Two viton seals off UK ebay, got better value than local specialized stores.
seal1
seal 2
They are fully viton with metal cage moulded inside, rather than outer metal ring with only sealing lip being viton.

2 main bearings 6206 C4, 63/28 C3 (23.67? both), 2 viton seals, combined shipping (16.86?)
4 shaft bearings 6203 x 2, 6205, 6305 (19.6? all 4)
2 drum bearing HK 3512, HK 2512 (12.24? both)
3 outer seals 2-3? each
a few small bearings for PV and WP 3? each
EDIT: ? = EUR

All SKF, NTN, INA (FAG) in correct clearances. No China products.

This goes for '08 and later engines, which use left side ball rather than the expensive roller bearing, which is $45 in itself.

All combined and converted to $ totaled in 97,4 USD for full engine seals and bearings.
With the roller bearing used in '07, it would total $132.

 

[Zman]

Thank you for the follow up. Those prices look closer to what I recall spending last time I did the job.

 

[RockefellerGG]

Well, Photobucket stopped allowing 3rd party linking of images unless I pay $400/year.

In the next week or so, I'll work on finding a new image host.

 

[braaaplifejonesing]

Here we go! Time to split the cases:


Clutch Disassembly

Start by removing the clutch spring bolts, the springs and spacer:


Slide out the clutch press plate, the friction discs and steels:


Drive down the safety washer using a hammer and screwdriver or punch:


Remove the clutch hub nut. This is pretty easy with an impact wrench, but you'll need to hold the clutch hub. It can be done with a standard ratchet set, but will take some patience.

Ok this is proving to be difficult for me as I'm using a hand wrench. any tricks to getting this hub nut off? its regular thread right? How do I hold the hub boss it seems so easy to damage? Im only trying to remove the kicker shaft to replace it. can it be done without taking out the clutch? Didn't seem as though its possible.

 

[Jakobi]

Lefty loosey. Should be around 70Nm on it from memory. Easiest way is to give it a couple ugga duggas with with impact (electric or air).

Otherwise there are basket holding tools you can use but as you've stated the basket is quite soft. You could also try applying some downward pressure onto the plates themselves. That may add enough friction to hold everything in place while you (or someone else) cracks the nut undone.

 

[Desert Silver]

The flywheel that's mentioned when you removed the crank gear. Is that what GG called the counter balancer?

 

[Zman]

The 1998 EC250 bikes had a separate counterbalance shaft which is different.

 

[5valve]

Is it a known fact that GG uses rotational specific viton seals on crankshaft, ones with grooves, or are they plain viton only.

 

[Zman]

I think it is a generic dual lip viton seal.

 

[Jim_C]

I sent a list of replacement parts and work needing to be done to Hall's Cycles in Springfield, IL. I've had good luck with them in the past and they will continue to get my business. The packaging all says gofasters on them... so I guess they all came through the dealer network. I bet I could have sourced all the parts individually, for less, but it was nice to send them a box of beat up parts and have a box containing all the good stuff in one shot:

Crank Bearings:
WORL: NJ206 EM C4 ME250112013 $42.99
KOYO: 63/28C4 ME20912006 $74.99

Crank Seals:
ME250112009 $24.50
ME250112008 $34.99

Complete Gasket Set: ME250544100 $134.99
Kick start seal: ME25632021 $12.99
Water pump Seal: ME25610011 $29.99
Selector Seal: ME120136048 $3.25
Primary C/S Seal: ME25636024 $13.50
2 Primary C/S O-rings ME25632025 $9.98

Piston: $189
Connecting Rod Kit: 09230125 $106.99

Rebuild and Labor:

Rebuild the crankshaft and balance: $98
Clean up the damage to the head: $35.00

Re-plating the cylinder: $250
Hall's sent this out to a shop called Millenium. It looks fantastic. Pics to come soon.

I just split my case last night. 2012 EC250R. The crank bearings are rubber sealed. I don't know why the factory did this. There are oil galleys for pre-mix into the case. Why a rubber sealed crank bearing from the factory has me puzzeled.

 

[5valve]

To protect them from lubrication.
If you look at bearing code description, it uses its own lubrication. It was environmental joke, so you could use less % premix.
Just pull the seals out on new bearings.