Help with a MZ 251 on N Plate found in a barn

[coxo2609]

Hello hope someone can assist.

A friend and I have found a MZ 251 in a Barn on his farm. initially it was seized solid as it hasnt been touched since about 2000.

We managed to free this up in the inconventional manner of a piece of wood and hammer. To our surprise when we turned it over it ran and we got a hour or so of running time out of it. It then proceeded to fail in generating a spark and getting fuel through.

We wanted to try and repair this at very minimal cost as a bit of fun. We have replaced the fuel lines and cleaned the carb out replaced the spark plug and Ht cap at little to no expense. No joy so far

Anyway that is the story i hoped someone on hear would be able to point me in the direction of a repair manual I obviously dont want to rip off haynes or spend money on said manual. Is it possible, Anyone have further ideas

Hope this makes some sense

Thanks Oli

[Old Dog]

The manual is available from the MZriders club - but it ain't free so I expect you're jiggered if you don't want to pay for it.

You need to start with the usual and obvious stuff first and see where that takes you.

[coxo2609]

Thanks Mate

[DAVID THOMPSON]

the points may look good but the return spring goes bad over time

if it has points keep this in mind
dave

[Kenney]

You could buy the MZ CD from Jane the club Regalia officer they are priced at only £6.00 post paid and it does have the full manual in english plus loads of other useful & informative information.
Hope this helps.
Ken

[Old Dog]

I suppose offering advice is what these forums are about, but it seems reasonable to expect people to take some responsibility too. This forum cannot (at least in my view) take the place of a manual.

Fuel: Take off the tank and clean it out, remove and clean the tap including the filter at the bottom of the tap. I would use a can of WD40 with the straw to make sure that everything is clean in the carbs especially the jets. Don't meddle with the float heights -there ought to be no need. Check the tap works ie: fuel comes down the hose - it is all about applying logic. If this works then the plug it into the carb. While you're at it, make sure the choke bung on the carb is not stuck at the bottom or come loose. This would kill the bike once warm.

Spark: Check the battery is charged and living, it may be that it has died with time (they do all sorts of funny things with duff batteries, despite barely needing one to run)
Assuming the battery is good. Remove the seat and clean thoroughly the earth point and all connectors.
Replace the fuses and clean connections, checking the tang grip is good.
Spark Plug into HT cap and look for a spark on kick over by holding next to engine barrel, this is best done in the shade. Keep replacing components one at a time starting with spark plug back to coil. This assumes that you have already checked you have clean and good connections. If it is points ignition this will need to be checked, serviced and reset.

The starting drill from cold is two or three kicks with the ignition off but the choke on, then choke off, ignition on and no throttle tll it fires.

They are very simple and need very little encouragement to run but you need to do things systematically.