Benzhou yy250t-4 By crittergitter (Read 5,863 times)

[JR]

Go back to the manual I sent you to and on page 151 starts the water pump assembly and installation. the linhais water pump comes in a one piece unit and slides in the hole in your picture and bolts up with 2 bolts. Very important the bottom allen head bolt is the fluid drain bolt and has a copper washer, this MUST be on this bolt or it will leak.

As you can see the water pump has a o-ring on the housing side that inserts into the hole or slot. It has a slotted shaft that slides over the rod in the engine that turns it. It's the same shaft that turns the oil pump on the other side of the engine so make sure it slides in alignment, you can turn it until it does just this.

The Chinese are the ones that put the silicone looking sealant on the engine and you need to carefully clean this off and re-apply a thin coat of the High Temp RED silicone gasket maker on this to insure a tight seal. I hope they send you a new o-ring for the pump in your gasket kit, use it.

I wouldn't take any chance on that water pump if it doesn't look right, heck you can buy a new assembly cheap;

.ebay.com/itm/Water-Pump-Assembly-for-250cc-Linhai-Yamaha-Water-Cooled-Engine-Scooter-Moped-/180813142574?pt=Other_Vehicle_Parts&hash=item2a194d9a2e&vxp=mtr" rel="nofollow" target="_blank">.ebay.com/itm/Water-Pump-Assembly-for-250cc-Linhai-Yamaha-Water-Cooled-Engine-Scooter-Moped-/180813142574?pt=Other_Vehicle_Parts&hash=item2a194d9a2e&vxp=mtr

It doesn't appear this one has the o-ring though?

JR

[richardthescooter3]

Welcome Crittergitter, were glad your here, you have come to the right place great guys & gals, ready to help whenever needed, Great Information, Great videos. You will be scooting before you know it

[crittergitter]

I hope your right. Im still waiting on my gasket kit. Ordered from scooterparts4less on the 26th and its now the 30 and its still not here. i know thats only four days but i get to look at the scoot all the time just setting on my porch tore down waiting for me to ride the darn thing.

[crittergitter]

Ok so i got everything put back together, and i forgot to put the thermostat back in. Is the thermostat a must? i know on cars their not but idk about this thing. So the temp gauge started getting hot so i watched it. got almost to the h and i shut it off. The fan never kicked on, and for some reason the coolant system wont burp, or move. after removing the "radiator" hose cap and watching it run, the coolant does not circulate either. am i missing something? help asap please.

[JR]

Yes it's mandatory to have the thermostat in, she'll never run right without it. Not circulating is only one of two things, it's stopped up or the water pump is not working.

As far as the fan not coming on if it has the slightest bit of air in the system the fan will not work right. You did verify the fan is good before you put it back together right?

The burping process can be tough sometimes and take several tries but it's a must. Need to make sure the water pump impellar is moving and get the air out and for sure put the thermostat in.

JR

[crittergitter]

what is the simplest way to test the waterpump? take it out hook my drill up to it put it in some water and turn it on? Tomorrow, i will put the thermo in, and i suppose ill try to find a way to test my fan. and for the burping. i see no coolant hose that goes to the carb, or any that i can unhook for that fact. i did take all the ones off i could and blew threw them just to make sure nothing was stuck in there.

[JR]

Good question on the water pump? I would remove it and then turn the engine over and make sure the shaft that you can see in the engine is turning. The one that the water pump splines into when you install it. The water puimp comes apart easily and I would look at the impellar and make sure it looks good too, you can use red silicone for the gasket if you mess the gasket up. Like I said it didn't make sense it was removed?

The drill idea might just be a good one even better if you could put a hose on it and gravity feed water to watch the flow.

You also couild drain the coolant because it is messy and fill the radiator with water and then unhook the outlet side of the water pump and turn the engine over and watch it? I would pull the sparkplug wire so it would not run.

Testing the fan is easy, just locate the thermoswitch at the bottom left side of the radiator and apply 12Vdc to side of the switch that goes to the fan if it comes on the fan is good. Since you're going to drain it to check the pump and/or put the thermostat in you could test the thermoswitch along with the thermostat to make sure they are good.

Using a meter set on ohms put each lead on the terminals of the switch and it should be open (no resistance) and then heat water in a pan. Put the sensor end of the switch in the water and when it reaches the 165 to 170F heat range the switch should close and you will read full ohm resistance or continuity.

I would test the thermostat also with the hot water, cold it is closed, in hot water it should fully open. Might save you a lot of trouble by testing these while you have it down?

Hoses to the carb are not used anymore but they still put the hook up on the carb don't worry about them.

I'll stress again and many people know this any and I mean any air in this system will make it act stupid. Burp it, run it around the block, let it get bone cold, burp it again. The fan will not act right with air in the system period.

JR

[crittergitter]

ok thermostat works, installed, and trying to burp the system. The water is now flowing... actually like spitting out of the hose when i take the cap off. Is there no easier way to get the air out? This is not easy to do.... I have probably tried 5 or 6 times to burp it, run it till it gets warm, well almost hot. Shut off, then let it cool. Take the cap off and it wont even hold 1/4 cup of coolant... im begining to wonder if their is even air in it..

[crittergitter]

so i went back out to see if it would hold anymore water... And it wont start, ive been aware of this issue.. but until now ive been able to make it start. I am getting fire, but a weak orange fire. Until now if i jiggle the wires coming off of what i am sure is the coil, it has the plug wire coming out of the other end of it, it would start. now its not even trying. javascript:adds(" ")
Any ideas?

[crittergitter]

I give up. I do not know how you guys deal with these things. Checked my oil, antifreeze in it.... I just changed the friggin head gasket. Im done I hate china

[tankrider]

Don't give up yet. I can't help you because mine isn't water cooled. Just be patient and listen to the great help available from the other members on this forum. It's all a learning experience; one of these days you'll be giving advice to someone with the same problems you have now. HANG IN THERE!!!

Sent from my DROIDX using ProBoards

[crittergitter]

well does anyone have any idea as to why after 4.5 miles the new gasket would go bad?

[rp]

Just a little info on the name game.

I have a 2008 Roketa MC-62-250, Which has the same engine. My user manual refers to it as the XY260T-4. JR sent me a wireing diagram for the VOG 206 and it was the same as mine.

I just got a new carb for mine and the packing list refered to it as a 260 carb.

Sometimes the same engine and etc. are use on different scooters with a little different name.
Its just a little confusing at first

Happy and safe travels

[crittergitter]

Well im pretty familiar with my scoot, its classified as a mc-250-e or a yy-250-t-4. It has the 257cc linhia in it. I found out i have a short somewhere in my ignition going to the plug. wiggle the wires and you can get it working. not sure if its a bad coil tho. And my engine just blew a new head gasket after 4 miles. So im gonna try one more time, except this time im gonna try the spray on copper stuff. Hopefully nothing got warped. This scoot had me so mad today, well more disappointing. Hopefully ill get it all figured out. Ill post some pics tomorrow just so you guys can get a look at it.

[JR]

OK two things while you're waiting for the new gasket you need to fix the short probably a wire that's rubbed and just needs repairing? Second drain that messy oil and just sit a pan under it and let it drip. Even when you start it up again put new oil in let it warm up and drain and replace.

The copper coat is a good idea and here's another. The YY250 manual has the torque values for the head bolts. After it warms up, let it cool ,going to do that for the burp any way and then RE-TORQUE the head bolts/nuts again. The gasket will shrink after it heats up and if you don't re-torque the head bolts/nuts you are asking for trouble.

Here is my burp system;

thescooterprofessor.proboards.com/index.cgi?board=cool&action=display&thread=24

Yes if you add 1/4 cup it had air. The burp sometimes will won't to make a preacher cuss but as I stated in this tutorial it maym have to be done several times. Got to ge the air out.

Also if you got it hot after cooling it while trying to burp it then that's another reason the new head gasket blew. Again re-torque those head bolts/nuts.