Tomos problem: does start, but dies a slow death..

Hello fellow's

I sure hope there's someone out there who can help me with my problem.

My lovely girlfriend has got this Tomos from about '90 with a A35 engine. She hadn't driven it for 2 years when she suddenly got the idea to get it up and running again. So she stripped the whole thing apart (with a little help from me, of course...) bought some reasonable expensive metallic carpaint (bright blue and titanium grey) and a month later she'd got it all screwed back together to unveil the greatest looking Tomos ever made! (Special paint, new springs, exhaust, tires, side-stand etc.) And 90% done by herself. (I'm so proud...) (Hey, and she can cook too!!)

So, finally the great moment was there. She started to kick some kickstart to find a very unwilling engine. We traced the problem to a total lack of spark. (I've never seen here more dissapointed..)(uh..well..I did, but that comes later)

I couldn't get a proper spark out of the engine myself (believe me, I tried..) so I just removed the engine frome the frame, and drove to the nearest dealer. and the next dealer, and the next dealer, to finally find one who had some proper advice: Change the points. All set and done. Points changed. Engine in frame, girlfriend desperately waiting to start the thing. (Hey, come back, I still have to put the Sparkplug in...) Yes !! We've got a running Tomos.

Only to find that it only runs for about 20 metres (60 feet). It runs great on choke, Always starts after two kicks, with a lot of blue smoke, which dissappears the moment we apply some gas (choke off). It then drives off without any problem, trying to lenghten here arms (Oooo, it pulls really nice !!) But after the mentioned 20 metres it just goes blaaaaaaaaa, pop, bang, blaaaaaaa....silence...

(Now she really is so dissapointed I'm really scared she's going to have a big nervous-break-down...)(Which means I have to cook, so please, help me !!)

What have I tried:

- Disconnected all elecrical wires, except the two or three necesserary)

- Tried another exhaust (here old one)

- Fitted another condensator (changed all the wiring bit there too)

- Tried some messing with points clearance settings

- Tried another spark plug

- Cleaned the carb

- Cleaned the fuelswitch (don't know the right word)

- Tried another membrane

- Checked the coils (also the one connected to the plug)

What I still haven't tried (but am going to try:

- Messing with the spark's timing

- Replace the crankcase sealings

- check to see if she maybe put diesel in it...

Do I need to say more? I'm really getting a bit frustrated by now, not to mention the girl. This Tomos has always driven really fine, without any problem. Now we have given it some proper attention, put a vast amount of time in it, and didn't do anything special to the engine, and look what we've got now...

I'm gonna send a really nice picture of a blue-smoking Tomos-super-special to anyone who can give me some proper advice. (And if she's in the mood, you can get a happy smiling face from her too !!!)

Thanks for listening


Re: Tomos problem: does start, but dies a slow dea

could it be a fuel prob.sounds like you are't getting enough fuel if your using the the jet clean line it fuel to carb. is the bowl filling.intake gasket good. just some suggestions.

Re: Tomos problem: does start, but dies a slow dea

As Fred would say:`Dirty carb,dirty carb,... You have to make sure you're getting clean gas/oil mix to the carb and thru the carb.Probably some little passages and/or main jet clogging.And check the coil wire and connections.Install an extra in-line gas filter,and make sure your oil injection still works.BYE!

Re: Tomos problem: does start, but dies a slow dea


- Jet is clean! I've blown it clean with the air-compressor. With no effect.

- Fuellines are fine! (Hey, we are talking professional overhaul here..)

- Fuel IS flowing to carb. No air bubles whatsoever.


- bowl filling gasket? You mean that little circular gasket that's positioned at were the fuelline is connected to the carb? The girl noticed some fuel around the carb, and showed me were it came from (Yep! gasket..) But I, experienced Moped mechanic said: No,no,no, that's fine, it will dissapear when the gasket is growing...

Will change that bastard asap.


Re: Tomos problem: does start, but dies a slow dea

Dear Don,

Carb is clean. 100% sure. I've treated the whole thing to a nice clean-up AND got to ALL the small passages. Coil wire will be tested again. (just to make sure). But if it starts really fine, it must have a proper spark. And to my opinion it would be very unlikely that the spark would dissappear at higher revs. (Although the engine does sounds exactly like that..).

No room for a gas filter. Oil injection on a A35 Engine?..come-on...that must be a joke?

Thanks for the help anyway.

Picture will be on the way, the moment it is repaired...!

Vincent (really don't wanna cook)

"Runs great on choke "

That... Vincent 'doan wanna cook'... is your clue that it is still a plugged fuel passage.

Why would the spark ignition fail the minute the choke is flipped off ?

It wouldn't.

Bear with us and put your nose to the grindstone and take the carb off again and very thoroughly clean and BLAST out EVERY orifice with high pressure compressed air after using aerosol carb cleaner in them.

And there is definitely room for an inline fuel filter.... get one and install it.

If you give up and take it to be fixed... they are just going to charge you $30 an hour to do what I just said.

There must be a stubborn bit of crud in a fuel passage.

Re: Tomos problem: does start, but dies a slow dea

Hey,Vincent! I'm not kidding about oil-injection.A lot of Tomos mopeds with a 35 have oil injection.I have 4 Tomos and they all have it,so you'd better check or TALK ABOUT a rich mixture....I have a Silver Bullet,Golden Bullet,Targa, and Blue Bullet.All have oil-injection! I want that pic.and she will be in a bikini,right?LOL

Re: "Runs great on choke "

Just wanted to add to what fred said.

You may have cleaned it well the first time but trash may still exist in the fuel tank and went right back in the carb so add a filter or clean the tank before you try to start it after cleaning the carb again.


Re: "Runs great on choke "

Ummm on another note check the air filter to. If it's a ghastly shade of brown it's the source of your putting and make sure your plug is set right. It should be like the width of a nickel or less. Work with me people!

Re: "Runs great on choke "

Reeperette /

A - What kind of plug ? There's a couple you can try, and some mopeds are funny about which one they like.

B - DelLorto or Encarwi Carb ?

If it's Encarwi, check to make sure the float is not upsidedown (pointy end goes UP) - if it's the DelLorto....check to make sure the float is not way to do that is to check the diagrams for that carb at - and look real good at exactly how it goes together, cause it's easy to screw that up, and it would, possibly..cause the problem you describe.

C - Compression

I figure you've checked this already, but do a test and make sure.

D - Mixture

Check and recheck...I know it's a pain in the neck, especially where that carb is mounted, but it really is worth the hassle.

If that doesn't help, let me know, and we'll go to more detailed measures.


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