Model 92B Top End Woes

[thirdstone]

Well you don`t want to split the cases for nothing so I would think that its more reason to leak check . In any case myself and many others do a leak check after every assembly , its cheep insurance.
If you have to replace the seal the engine assembly is pretty easy , you have good schematics to follow and plenty of help here .

[brad100]

Thirdstone, do you have a thread on here on how you made your leak tester? I have the day off work and want to take a crack at it. Mostly curious on what you used for the base there, pictures explain everything else pretty well.

[Bullfrog]

Sorry, but I sort of glossed over the post which mentioned that things suddenly went rich and no amount of carb tuning would correct it. Suddenly going rich (probably with lots of blue/white smoke) is a very strong indicator that the clutch seal "blew" (no longer seals). Confirming evidence is the comment about blowing transmission oil out the vent. While that can be seen normally on a cold engine, it is most common when the transmission is over-filled (and it will "find" its acceptable level and stop blowing oil out of the transmission vent when it gets to the correct level if the clutch side seal is still good). However, a blown clutch side seal can pressurize the transmission cavity and cause oil to flow out of the vent all the time. And a blown clutch side seal can cause "rich" running - well, not really rich in the sense of carburetion - but certainly "rich" in the sense that it doesn't run well and puts out LOTS of smoke.

You can bolt the cylinder and head on without piston to do a pressure test (um, tie down/immobilize the kick starter so you don't inadvertently spin the engine with no piston on the rod). I suspect the pressure test will confirm that you have a complete engine disassembly in your future. (Don't worry, you have lots of support here!)
Ed

[givergas]

heres what i did for my 1st time pressure tester. and i was apprehensive about getting into the engine rebuilt but once your in there pretty straight forward

[brad100]

Ed, that has to be it. A perfect description of my problem. I have consistently drained (leaned over on left side and held straight up) all transmission fluid, replaced with EXACTLY 20 oz, and she pukes up the red stuff 1/10 starts.

Even if the issue isn’t my top end, I’m glad I am in there to clean it up and make measurements. While I’m a bit pissed off that I cracked the bottom ring, the top ring looks very tired and stretched passed its gap. I’m Im guessing it would have required new rings anyways, or I would have wanted new rings (better compression) without ever knowing it.

While I’m now convinced that I need a crankcase seal regardless of if I have a leakdown tester to confirm it, I will like a tester for after everything is put back together obviously. I think I am understanding the concept of the tester, it’s now just deciding where to bolt up. I’m also wondering what you fellas used the layer above your gaskets on your tester. Just a piece of flat scrap metal with proper holes drilled?


Edit:

Engine is off and on my coffee table for exterior cleaning. Not as intimidating when it’s off the bike.

[Bullfrog]

Any method which seals and holds 6psi at the exhaust port/manifold and at the intake manifold will work. On the exhaust side, folks have used radiator hose/pipe clamps/rubber plugs etc. On the intake side - usually a flat plate drilled/notched as needed and a gasket. NOTE: Pressurize to 6psi only (9 psi max). Loss of 1psi in less than 1 minute is a FAIL.
Ed

[thirdstone]

Brad it sounds like you are on track to do it correctly. About 3 pages back on this forum there is s blog from Al on a tester. Basically plug the exhaust port and pressurise from the intake or versa visa.
You can use a pressure bulb from a blood pressure cuff (eBay) or a bike pump. You need a low pressure - pressure gauge , the ones used on inflatable dingy’s are ideal and very cheap. Some sort of small pipe for the hose connectors. A bit of sealant and you are done. The base plate is only required is you are testing with the cylinder removed.if you are going to commit to a seal change , as the symptoms demand then just test when fully assembled . Just remember low pressure testing. I wouldn’t use a compressor as it’s a bit hard to Control and you could blow out the left hand seal. I’m sure you will work it out, there are many ways to do this .
I forgot to mention that old car inner tubes make great material for reusable seals on the test gear. I get mine from a tyre replacement garage , they are very happy to let me have the punctured tubes.

[Dale]

Ed, that has to be it. A perfect description of my problem. I have consistently drained (leaned over on left side and held straight up) all transmission fluid, replaced with EXACTLY 20 oz, and she pukes up the red stuff 1/10 starts.

Even if the issue isn’t my top end, I’m glad I am in there to clean it up and make measurements. While I’m a bit pissed off that I cracked the bottom ring, the top ring looks very tired and stretched passed its gap. I’m Im guessing it would have required new rings anyways, or I would have wanted new rings (better compression) without ever knowing it.

While I’m now convinced that I need a crankcase seal regardless of if I have a leakdown tester to confirm it, I will like a tester for after everything is put back together obviously. I think I am understanding the concept of the tester, it’s now just deciding where to bolt up. I’m also wondering what you fellas used the layer above your gaskets on your tester. Just a piece of flat scrap metal with proper holes drilled?


Edit:

Engine is off and on my coffee table for exterior cleaning. Not as intimidating when it’s off the bike.

Just making note of your description for the oil drain and fill. There is no way to completely drain it through the drain hole. So if you replaced it with 20 ounces of new fluid then you have from 4 to 6 ounces too much in the case.

This could be the cause of the oozing but doesn't diminish the need to validate your seals.

[Al Harpster]

A long thread here .......

Summary:

Poor running condition resulted in owner removing cylinder and disliking what he saw.

In furtherance of this disassembly a piston ring was broken.

Now that the top end is off a diagnosis of the initial complaint begins.

If money well spent is a concern, I'd stop and ponder for a bit.

If you pressure test NOW you will know.

It's going to be cheaper to pressure test now and proceed with knowledge.

Harbor Freight Item#62637 can be had for $11.20 with the 20% coupon you print from the web.

Add the dribs and drabs shown in my forum post pictures and you're out $20 total.

Put the top end back on. You don't need piston rings to pressure test. You don't even need a piston. Need a base gasket or intake gasket? Make one.

Pump it up and find all the leaks you see with the soapy water test and fix them. Base gasket leaks, intake manifold assembly leaks, head gasket leaks, you name it.

Wont hold pressure? Spray soapy water around the transmission vent pipe & see if it bubbles. That's one of your crank seals.

Then you will KNOW, not surmise.

Then you'll KNOW the purchase of a flywheel puller, an impact driver for the case screws, crank seals are the minimum.

AND after all that .......you'll have the pressure test tool to check that your work is right and the poor run complaint is something else.

Ain't worth doing all that work without knowing.

Ain't worth doing all that work without checking it's right immediately after doing it.

20 bucks is gonna look like lunch money once you dig in. Once you start digging, the money flows real good.

[Bullfrog]

Very good summary Al! I can't remember which mentor it was at PABATCO/Hodaka (Harry Taylor, Jim Gentry or Marv Foster) who once asked me, "If you don't have the time to do it 'right' now, when will you have the time to do it a second time?"
Ed

[Joe Ormonde]

Do you intend to keep the bike or (FIX AND SELL) ? As far as Pistons and Rings go there are PLENTY out there in private hands. Problem. At one time I was generous with hard to find Classic Car parts and once I hooked them up with the parts to finish lets say a 57 Chevy, they sold the car! What a Fool I was! Now, Model 92 Pistons and rings ARE NOT hard to find, it`s just hard to find Hodaka fans that want to let them go. Far too often generosity is a one way street! I`m going to watch Scrooge now. Humbug! Joe Ormonde.

[brad100]

Alright guys, I am back with a pressure test that took me about a day and a half to make leak-proof. Won’t hold 6psi for longer than 1 second, and takes about 15 seconds to leak empty. All of my cork gaskets that I made are holding up. I hear it blowing out of my clutch side. I see the bubbles forming from what I believe is the transmission vent. I’m glad to know the seals are an issue prior to splitting the case..

Feeling a little overwhelmed haha. I need to reorganize my tools and get a workstation set up in the house. I’ve been labeling all parts and placing them in baggies, so I’m not losing anything yet. I have not been able to track down a pin wrench/spanner wrench to get the clutch and stator off. I have the bolt type wheel puller set from HF for the flywheel. I’ll try Walmart tonight as a last resort for the pin wrench...don’t wanna wait for shipping around the holidays.

Al, one hell of a summary. You hit the nail on the head. I was a bit impatient to find the root of my problem, and in doing so I broke a pretty important piece to the puzzle. I’m learning a lot about my engine, but also about patience.

Joe, I do intend to keep it. I’m obsessing over it now. I’m not sure if that would be the case if it wasn’t for this forum and the ability to connect with you folks. I’ve also got a lot of hours invested in it, and I’ve really bonded with my Ace. I wish I was riding it more, but the amount of information I’ve learned and continue to learn about small engines and Hodaka makes it worth it. Joe, are you perhaps saying that you have some rings available?

[thrownchain]

If it's leaking thru the vent, you're looking at the right side crank seal. Motor apart to replace, and as long as it's that far down it makes sense to do all the seals. And as long as you're gonna spend money, make the motor new, only way to know that it will last and you can ride for years to come. Also zip lock bags can are a good parts storage unit.

[matt glascock]

I'd add that while you have the cases split, consider changing the bearings and possibly the bushing. Its good policy to change the bearings during a motor overhaul. $40-50 bucks or so for parts and you will have a mechanically new motor - at least up to spec. If you don't want to deal with that or money is tight, a least clean and examine the bearings. If they don't rotate smooth as silk or there is any perceptible slop/run-out, they really have to be changed. I've been talked through the process on this very forum. Trust me - if I can do it, anyone can.

[Al Harpster]

Here's a couple money saving tips:

DO NOT USE ANYTHING OTHER THAN THE CORRECT FLYWHEEL PULLER. Screw up the flywheel and you're in for some long dollars replacing it. What ever you bought for a puller from HF, take it back for a refund and put the money where it will do you well.

BUY THE CORRECT 'FORK' TOOL. YOU MIGHT GET AWAY WITH A STRAP WRENCH TO HOLD THE FLYWHEEL (AND CLUTCH) WHILE TAKING OFF THE NUTS, BUT WHY BOTHER? A poor functioning holding tool can lead you to trying things that don't work and result in damaged parts.

DON'T BUY THE CHEAP IMPACT DRIVER. BUY ONE FROM AN AUTOPARTS STORE WHERE YOU CAN RETURN IT IF YOU DON'T LIKE IT. Be picky about how the impact driver performs. Poor performance results in trashed screws. If you don't get immediate good results using the one you buy, return it and get another. When you hit that driver with a hammer make sure everything's on solid footing.

BEARINGS COST MONEY AND ARE HARD TO REPLACE. You're not getting the crank bearings out with out a GOOD set of Medium Size snap ring pliers. $20. Cheap ones from HF I bought went into the trash after bending. Pressing out bearings requires solid setup and a bunch of heat. You're gonna need a solid work bench. Or you can by the baby hydraulic press from HF for another $70. AND really large sockets to contact only the OD of the bearings to press in. AND gloves to keep from getting burned from the hot cases. Bearings don't like to come out cold.

TAKE TIME SEPARATING CASES, THEY WON'T TAKE A BEATING. Get a plastic face hammer, blocks of wood for tapping etc. Crack one of these and you've got real trouble. There's an old tech bulletin on the web, something like " Jim Gentry Cracks Cases" that could help assure success. Get that.

[brad100]

Hmm, I’ve got some thinking to do this weekend then. At $150 for the engine overhaul kit, $60 for the “correct” fork tool and flywheel puller, $50 or so for an impact driver and snap ring pliers- this is a large investment for a first time engine overhaul. Especially for an engine without piston rings. Kinda takes the wind out of my sails.

I have nearly $500 in it now, with the initial purchase, getting it titled, Motion Pro doodads, handlebars, shocks, cleaners, tires, tools, miscellaneous. That’s a lot of money (to me, broke college kid) for a 48 year old, non-running, 98cc air-cooled 2 stroke. I don’t necessarily have the emotional/nostalgic attachment to the machine that many of you guys do, though I do love it.

Guys, thanks as always for the advice.

[thrownchain]

Welcome to the world of old bikes.

[brad100]

Ugh, I’m hoping it’s not my sayonara to old bikes. Trying to decide whether or not to throw in the towel- whether or not it’s financially irresponsible for me to continue dumping money into it. I could do all of this work (and more detrimental, spend all of this money) for it to NOT work. A lot of “what if’s” are rearing their ugly mugs.

[matt glascock]

I wouldn't throw in the towel just yet. We've all been spending your money hand over fist and there are certainly ways to reduce the expense of getting your motor buttoned up. We've all improvised many times, and if your goal is to get the bike running again, a lot of what has been discussed may not be necessary. Before spending another dime, crack the cases and inspect the engine internals. I just cracked the case on an Ace 100 motor that looked like a pile of grease-encrusted crap and the insides were pristine. You might need to replace the seals only. A pretty inexpensive proposition.

[brad100]

Thanks Matt. I’m trying to not get discouraged. To me, thinking of engine internals is like trying to comprehend the size universe. Does not compute...yet. I do have the will to learn, albeit I am apprehensive to spend too much money, or unnecessary money. And I take it that exploded diagrams tend to make things look scarier and more complicated than they are.

Wishing that Strictly Hodaka didn’t have that 10% off purchases over $100 this month, as I feel like I’m on a deadline haha. Sounds like I’m going to need the fork tool, crank seals, and flywheel puller from there, at the very least- though I’ve read on this forum of taking the clutch assembly off with a gloved hand and a firm grip

Edit: Will these rings fit my Art piston, or keep looking?

https://www.ebay.com/itm/HODAKA-ACE-100 ... Swe9VcHQtI

[matt glascock]

Before you get rid of the fly wheel puller you have, check it out to see it it will work. Remember, when you thread the puller onto the fly wheel, make sure the central driving bolt is nearly all the way out and, of equal importance, the tool threads onto the fly wheel "LEFTY TIGHTY". You only need to thread it onto the flywheel hand tight. Try yours out. If it doesn't fit, let me know and I will send you mine to use if you promise to send it back. Ditto on the clutch holding tool. I'll even throw in the return postage.

[thirdstone]

Hi Brad all is not lost. What everyone here is telling you is very true and wise. However there are two ways to skin a cat (what a horrible saying ) .I live in Australia and the correct tools are difficult to buy so I`ve had to be resourceful and I don`t have a Matt helping me out, I`d take him up on that generous offer.
The flywheel puller is a must, no two ways about it but not expensive .
The holding fork (used for clutch and primary gear) can be made up with scrap metal, all the better if you have a stick welder. You just have to use your imagination, Just use Matt`s.
Do you have a BBQ ? if so then here is the answer to your bearing removal and refit. With the cases heated up the bearings will fall or tap out and push or tap in. Just remember to clean the cases before you heat them up unless you want the next meal to taste like transmission oil.
Remember the clutch nut is Left hand thread. If you or a mate have a rattle gun or impact driver drill you hardly need the holding fork for removal. Don`t use the rattle gun or drill for reassembly though.

[thrownchain]

Don't get discouraged, if you can borrow or make the tools you will need, then things will go easier. As for spending the money, the more you renew on or in the bike the longer it will last with some basic regular maintenance. And finally the best part is if anyone asks you can smile and say "yep I did it myself".

[thrownchain]

Also when people find out you're into old bikes, old bikes will find there way to you.

[thirdstone]

I ended up buying one of these . Best money I ever spent.it can be used in multiple engine types. That’s Aussi $$ too, take off 1/4 for USD