Trailboss 250 problem, Help please
#11
08-02-2007, 05:24 PM
Trailboss 250 problem, Help please
<div class="FTQUOTE"><begin quote>Originally posted by: SKC405
I have a 91 trailboss 250 that has been sitting for 2 years. I cleaned the carb and still can't get the damn thing started. Someone told me the crankcase seal may be bad. Would this make starting the atv difficult? If so, why? Does it draw a vacuum? Next question, how hard would this be to replace? Thanks in advance.</end quote></div>
I just went through this with a 94-400l. Would not start unless I put gas right into the cylinder and then would stay running only at higher RPMs, if I let go of throttle it would die. Anyway not to bad to change if it is the outside crankcase seal. It is located behind the drive clutch [will need a puller to get it off] Mine was very obvious that it was leaking once I got clutch off, it was completely sticking out on one side. I replaced it by pulling it out with dental picks, then used a piece of 1 1/2" PVC pipe to tap in new one. Also put a little PermatexII on it. Then used the bolt that held clucth on and a big fender washer, cut PVC to correct length, put bolt through the PVC pipe and tightened against seal a little to hold and let permatex set up a little.
I have a 91 trailboss 250 that has been sitting for 2 years. I cleaned the carb and still can't get the damn thing started. Someone told me the crankcase seal may be bad. Would this make starting the atv difficult? If so, why? Does it draw a vacuum? Next question, how hard would this be to replace? Thanks in advance.</end quote></div>
I just went through this with a 94-400l. Would not start unless I put gas right into the cylinder and then would stay running only at higher RPMs, if I let go of throttle it would die. Anyway not to bad to change if it is the outside crankcase seal. It is located behind the drive clutch [will need a puller to get it off] Mine was very obvious that it was leaking once I got clutch off, it was completely sticking out on one side. I replaced it by pulling it out with dental picks, then used a piece of 1 1/2" PVC pipe to tap in new one. Also put a little PermatexII on it. Then used the bolt that held clucth on and a big fender washer, cut PVC to correct length, put bolt through the PVC pipe and tightened against seal a little to hold and let permatex set up a little.
#12
08-02-2007, 07:56 PM
Join Date: Aug 2007
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
Trailboss 250 problem, Help please
Ok, I don't have a compression guage but I put my finger in there and it blew it out, no problem. I'm guessing there's more than 100 psi. The carb is not "drafting" out the back(breather end). I'm suspecting it is the crank seal. Now is there a crank case seal and a crankshaft seal? Or am I calling the same part 2 different things?
Secondly, I want to thank everybody here for your help and advice. I'm really starting to like this site.
-Steven
Secondly, I want to thank everybody here for your help and advice. I'm really starting to like this site.
-Steven
#13
08-03-2007, 09:28 AM
Trailboss 250 problem, Help please
<div class="FTQUOTE"><begin quote>Originally posted by: SKC405
Ok, I don't have a compression guage but I put my finger in there and it blew it out, no problem. I'm guessing there's more than 100 psi. The carb is not "drafting" out the back(breather end). I'm suspecting it is the crank seal. Now is there a crank case seal and a crankshaft seal? Or am I calling the same part 2 different things?
Secondly, I want to thank everybody here for your help and advice. I'm really starting to like this site.
-Steven</end quote></div>
Yes there is more than one seal in the crankcase. I don't know which one is called what but if it is the one behind the drive clucth it is easy if not you will have to pull the crankcase out and split it open
Ok, I don't have a compression guage but I put my finger in there and it blew it out, no problem. I'm guessing there's more than 100 psi. The carb is not "drafting" out the back(breather end). I'm suspecting it is the crank seal. Now is there a crank case seal and a crankshaft seal? Or am I calling the same part 2 different things?
Secondly, I want to thank everybody here for your help and advice. I'm really starting to like this site.
-Steven</end quote></div>
Yes there is more than one seal in the crankcase. I don't know which one is called what but if it is the one behind the drive clucth it is easy if not you will have to pull the crankcase out and split it open
#14
05-03-2009, 08:12 PM
Hi
Did you ever get your 2 cycle fixed - was it the Crank Seals ?
I have an 86 Trail boss 250, I have the same problem with it not wanting to Idle, I have rebuilt the Top End (new Piston, Rings and Honed Cylinder), Compression is very good but once it is running, It goes from a Hi Idle - the Pilot Screw has almost no effect where it is adjusted to stalling when We switch riders or just come to a stop, I too was told to check for an air/ Vacuum leak thru the crankcase but am finding it hard to find ways to block off the Intake and Exhaust ports properly. Should I just take it to the Dealer and "Bend over" and close my eyes.
Thanks
Timmy from Connecticut
Did you ever get your 2 cycle fixed - was it the Crank Seals ?
I have an 86 Trail boss 250, I have the same problem with it not wanting to Idle, I have rebuilt the Top End (new Piston, Rings and Honed Cylinder), Compression is very good but once it is running, It goes from a Hi Idle - the Pilot Screw has almost no effect where it is adjusted to stalling when We switch riders or just come to a stop, I too was told to check for an air/ Vacuum leak thru the crankcase but am finding it hard to find ways to block off the Intake and Exhaust ports properly. Should I just take it to the Dealer and "Bend over" and close my eyes.
Thanks
Timmy from Connecticut
Thread
Thread Starter
Forum
Replies
Last Post
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)