Anyone with 2008 Linhai Engine rebuild Exp. ? By brndnpnt (Read 1,467 times)

[brndnpnt]

I know the time will come and I have the parts to change out on my motor when it has finely cranked its last time

I have messed around with a motor just like mine but whats involved and parts needed to bring it back to its youth again and with swapping the parts out. Yes, and I know I am asking allot but I have the parts needed to swap out from a young motor to my ageing motor but how hard is it if I have the two motors on a table ready for operation. Example splitting a motor and timing chain exct.

Sorry for such a complex question.

[JR]

No need to be sorry very good questions. A good manual to get on bolt torques and how to will be in the Yamaha section the YY250 manual.

Also a good thing to do is on things you're not sure on just simply take detailed pictures and notes as you tear the engine apart. label bolts and nuts and fix it to where the old saying applies "it goes back together the way it came apart".

Not only that it will make a good "help someone else thread for the future!"

JR

[brndnpnt]

Dec 29, 2011 6:11:16 GMT -6 JR said:

No need to be sorry very good questions. A good manual to get on bolt torques and how to will be in the Yamaha section the YY250 manual.

Also a good thing to do is on things you're not sure on just simply take detailed pictures and notes as you tear the engine apart. label bolts and nuts and fix it to where the old saying applies "it goes back together the way it came apart".

Not only that it will make a good "help someone else thread for the future!"

JR

Thank You, Again but what part goes out first on the motor is it the cylinder wall or cylinder?

[bhinch]

Very good point JR...I use freezer bags to label and keep the bolts etc. from ending up lost...like he said take pics...notes....the piston rings are the first to go on most gas engines....but it takes alot of miles.....how many miles does your scoot have....these engines are very tough....low oil and neglect are the common probs on any engine....scoot or car...metal to metal contact rules everytime....destroys the engine .....we are so use to turning the key and going...till the ride gives up the ghost and we wonder why.....the demise of the full service gas station has added to the prob....so self inspection of your ride is required...stay safe...enjoy the ride...

[brndnpnt]

Dec 30, 2011 2:00:04 GMT -6 bhinch said:

Very good point JR...I use freezer bags to label and keep the bolts etc. from ending up lost...like he said take pics...notes....the piston rings are the first to go on most gas engines....but it takes alot of miles.....how many miles does your scoot have....these engines are very tough....low oil and neglect are the common probs on any engine....scoot or car...metal to metal contact rules everytime....destroys the engine .....we are so use to turning the key and going...till the ride gives up the ghost and we wonder why.....the demise of the full service gas station has added to the prob....so self inspection of your ride is required...stay safe...enjoy the ride...

It has around 18,000k + or - because I had a broke speed-O-cable for a little while. I take very good care of this motor. I use full syn motor oil and only 93oct also form time to time I use seafoam or locus oil additive. It seem to run well but right now its burping sometimes when I give it gas and I think becasue I dont have the correct air filter right now untill I get a stock filter. I am useing a free flow filter with tape around it to keep it from being to free flowing and I believe the air is not leaveing the motor fast enough or I am running a little rich.

[JR]

A little rich means not enough air, open that filter up. For the most part with good maintenance and normal driving conditions and wear and tear one will see the rings go first on one of these little engines.

Evidence of them getting bad will be burning oil. loss of compression and power. But one has to remember this is a water cooled engine which generally allows more miles and wear. 18k on her and she's till running good is testimony to you taking care of her and when and if the day comes she needs a little TLC I would pull the head and mic it to see the wear and if it was still within OEM specs I would re-ring it.

Also I would pull the valves inspect them well and give them a good lapping for good measure or I might even buy new vavles seats and springs and replace them while I had it down a small cost to have it in great shape.

I might also consider a new timing chanin with new chain guides.

Lastly on this engine if I found the piston head wore considerably I might consider a 300 big bore kit upgrade, not that much more HP it actually only hits about 280cc with a 75mm piston but it does give one a little more ummmp over hills and such. You have to remember the the only difference between the 257cc and the 300cc is the piston size and bore. The engines are identical. You could even have your piston cyclinder bored if you have access to a good engine boring shop and just buy the piston and rings.

If one buys the BB kit it comes complete with head, piston, rings, and gaskets. People have done this with good success.

But at this point I would just keep taking good care of her and ride!

JR

[alleyoop]

If it is BRUPING it is running LEAN because of the Air Filter(getting to much air not enough fuel). Easy FIX Just richen up the Fuel Ratio give it a 1/4-1/2 turn Counter Clockwise.

If it POPS at a certain speed usually at higher RPMS it is RICH.
Alleyoop

[brndnpnt]

Ok i had it backwards thanks. Alleyoop my my moms husband wants a scooter trike. What scooter trike to you know the most about. Hes looking to use it for going to work. Also could you send me a link for float bowl adjustments.

[alleyoop]

Hi Brndnpnt,
Well as you can see I have the ICE BEAR 150 I got mine back in 2009. All the 150s are pretty much sameo sameo just some are lighter and some are heavier.
Here is what is available from ICE BEAR:
.icebearatv.com/150CC-Trike13.htm" rel="nofollow" target="_blank">.icebearatv.com/150CC-Trike13.htm

Now since he wants it to go to work it depends on what speeds he needs to be able to go to keep up with traffic.
If the speed limits are 45 then a 150cc would do him just fine. If speeds are 55 and up then he would need one of the 300cc Trikes.
Alleyoop
Here is how to adjust the Float in the Carb:

[n4zou]

I put 60,000 miles on my first Chinese scoot. The ignition sensor went bad so it just quit running. It had started using oil and was showing a little blue smoke out the exhaust. The body panels were ragged and needed to be replaced. The radiator had developed tiny leaks around the solder joints. The dash needed replacing too as the speedometer had become erratic. The seat had a bad case of ugly too. After calculating the costs of a total rebuild I determined it would cost less to just order a new scoot, which I did. If you service your scoot and take proper care of it you should be able to do the same. BTY, I never used synthetic oil. I used Rotella 15w40 diesel engine oil. Just before it quit and I started parting it out the oil showing on the dip stick at every 200 mile fuel fill up would be down by 3/4 so I would top it off. When it was new It would be down by half on the dip stick at the 1,000 mile oil change.

[JR]

Great diagram Alley and that is in the tech section too if needed. 18k and she's still running good and 60k on n4zou's scooter all testiment of good care and maintenace and not trying to make the scooter something it's not. Also Alley's trike even though he's done things to his it's always been on the note of improvement and not trying to make it something it's not and it's a 09 that's still carrying his old self down the road!

Good job guys! Next time I see someone saying the junk Chinese scooters I'll link them to this thread!

[damin69]

Jr, I am pretty sure that my issue is low compression on my Roketta. So doing a top end rebuild is what I am thinking of doing. Do you have any links to some good Top end kits including the 300 BB kit. This might just be right up my alley.

Now if I go with the big bore kit do I need to change out CDI or are they the same also?

Thanks,
Todd

[alleyoop]

You do not have to change out any Electricals your current setup will work just fine. You will have to mess with feeding the BEAST more FOOD as they say (AIR AND FUEL). So you may want to rejet your carb .
Alleyoop