Terrible engine sound Tomos A35

Sergey Smirnov /

Hello! this is my first time with a Tomos sprint moped. Terrible engine sound. What broke?

Terrible engine sound

Re: Terrible engine sound Tomos A35

That sounds like either a ring broke. Or rings are so bad that the Piston is slapping cylinder walls.

Re: Terrible engine sound Tomos A35

Yes$50 repair. New piston and rings for tomos a35 engine. You be in business!

Re: Terrible engine sound Tomos A35

Tweaker trash /

Club Tomos is a joke

Re: Terrible engine sound Tomos A35

Club tomos? Where is that located? This is the army!

Re: Terrible engine sound Tomos A35

So?? What was making all the noise? Did you take the top end off and look at the condition of your piston and rings????

Re: Terrible engine sound Tomos A35

Sergey Smirnov /

Not yet. Moped in a country house. Tomorrow I'll go and watch. It became very cold here)))

Вut I watched a lot of videos on youtube, and found that tomos make a same sound with a regular exhaust.

Re: Terrible engine sound Tomos A35

Sergey Smirnov /

Hey. I removed the cylinder and found that everything seemed to be fine with it, the piston was also fine and the rings were not broken. However, there was not a single gasket! Under the head and under the cylinder was just a sealant. Now the question is if I cut the top head pad out of aluminum, what is the thickness? 1mm? How thick should the bottom gasket be? Here in Russia just thick cardboard is often used (for bottom gaseket). And in appearance, this piston does not look like the original one from TOMOS.

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Re: Terrible engine sound Tomos A35

There is no gasket on the top part of the cylinder. Tomos only has base gasket. put a gasket on cylinder that is in first photo. About 2 mm thick. Try to use material that won't burn when engine gets hot. Let me know how it works.

Re: Terrible engine sound Tomos A35

Sergey Smirnov /

Good. Thanks. But the question is, why do I see head gaskets on sale?

Re: Terrible engine sound Tomos A35

Head gasket is optional. If your mating surface is messed up or you want a tad less compression you can put various thickness and material gaskets. As far as the sound it really to me sounds like the transmission is making all that noise. Also check the crank bearings for axial play when you get the transmission cover off.

Re: Terrible engine sound Tomos A35

I don't know what you mean by saying head gasket on sale. You only need Base gasket if everything in good condition. Make sure you only use 9 ounces of transmission fluid. And if the noise is affecting engine performance. Do as other guy said and look for abnormal movement in crankshaft. Make sure you pay close attention to where parts go if you take apart engine!!

Re: Terrible engine sound Tomos A35

Sergey Smirnov /

Now I'm trying to find a scan of the crankcase gaskets. There was a link, but it doesn't work.

Re: Terrible engine sound Tomos A35

Do you have Auto parts store in your area?? Go see if they sell gasket paper and Trace it and make gaskets for anything. I've made gaskets for my clutch cover on my tomos and they last longer than original.

Re: Terrible engine sound Tomos A35

Sergey Smirnov /

So I made two gaskets 2mm of paronite for the base and exhaust pipe. The terrible noise has disappeared!!! But still something is wrong. I brought the engine home, I'll see what's wrong. I bought new bearings very cheap))) about 12$.

I hope this is not a fake from China.

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Re: Terrible engine sound Tomos A35

♣Slew Foot♣ /

Tomoshop.nl

Re: Terrible engine sound Tomos A35

Sergey Smirnov /

> ♣Slew Foot♣ Wrote:

> -------------------------------------------------------

> Tomoshop.nl

There each bearing costs minimum 5 bucks. And we must wait. Here 12 for all together.

Re: Terrible engine sound Tomos A35

Those are fine bearings. Used in many engines. To replace those bearings you are going to be tearing the entire engine e down and even splitting the center cases to remove the crank.

Heating up the cases in the oven will make the bearings easier to remove, and warming up the new ones will make them easier to press in.

It sounds like you are limited in resources to make this happen so just be sure to take your time and ask questions if you run into any problems.

Re: Terrible engine sound Tomos A35

Sergey Smirnov /

So I took off the clutch cover and I found it there. And it also seemed to me that the clutch was rubbing a little against the gear. I can't unscrew it yet.

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Re: Terrible engine sound Tomos A35

Uh oh. That's not good. Sprag clip? Check your Piston clips of missing chunks too

Re: Terrible engine sound Tomos A35

Sergey Smirnov /

Piston clips in place and not broken.

Re: Terrible engine sound Tomos A35

I imagine that your sprag clip broke. The sound you are hearing may be the shaft sprag thingy getting angry(unsure of correct term)

I could be wrong, but that does look like the end of the starter shaft sprag clip. On a pedal start bike it stops the pedals from turning with the engine whilst riding. I'm not totally sure a kick start bike even has one.....

If so it's not the biggest deal.

Re: Terrible engine sound Tomos A35

Check that you have the necessary spacers in the clutch assembly too while you're in there

Re: Terrible engine sound Tomos A35

Sergey Smirnov /

Hooray I was able to remove the clutch !!! And it looks good. There was a single spacer under the clutch (it hangs on the shaft). All bearings look good.

I think, maybe you need another spacer for the clutch? (edited)

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Re: Terrible engine sound Tomos A35

check the exploded diagram in the manual but as far as i remember that's the only spacer there

Re: Terrible engine sound Tomos A35

Sergey Smirnov /

Ha ha manual? All I have is youtube, and kind people write to me here.

Re: Terrible engine sound Tomos A35

Re: Terrible engine sound Tomos A35

Sergey Smirnov /

Yes thank you! of course I have same guides.

However, they do not provide repair support, when you do it the first time.

Re: Terrible engine sound Tomos A35

♣Slew Foot♣ /

Replace inspect pads and shoes. You will thank me if you do it now instead of 3 months from now.

Re: Terrible engine sound Tomos A35

Sergey Smirnov /

It's just mysticism! Put the clutch and there was a gap!

Early the clutch rubbed against the gear. (edited)

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