We have a 2005 Bombardier DS 90 that has always ran great. First time trying to start it over the weekend it was a no go. I drained the fuel and added fresh, cleaned the air filter and it fired right up but it bogs down terribly when you hit the throttle. I just removed the carb and gave it a good cleaning (took apart carb, cleaned the bowl area, blasted carb cleaner through everything, removed the brass screw orifice, went as far I felt comfortable with). I reinstalled it and it is doing the same thing.

Any suggestions ? I'm a pretty handy dude but these small engines can make me scratch my head sometimes.


TIA,

Steve B. & Family

 

But did you remove the jets and make sure they are open?
If so, I'd do a compression check.
Pipe maybe plugged?

 

Ok I just checked the compression, I get just under 90 lbs of pressure and is not dropping.

ETA: It took 5 kicks to get it to 90 psi. I did nothing besides install the hose to the gage and kick. Is this correct ?

A quick search online tells me It needs engine work, dammit. I guess the pressure should read at least 120#.

Is this correct ? I wonder WTH happened ??

 

You can try it with the throttle wide open while kicking.
IMO, 5 kicks and 90 pounds isn't that bad. Maybe it's getting to the borderline on comp but I highly doubt it's causing this problem.
Anyways, you did remove the jets and made sure the holes are open. This really does sound like a plugged main jet.

 

DS 90 Carb Parts Breakdown and Part Names & #'s


When I removed the carb I removed 4,5,2,3,7,&6 in one piece and that stayed attatched to the throttle cable. 18 & 19 also had to come off and stayed on the quad when I removed it.

From there I had it in my hand and hosed it off with carb cleaner. I then removed the bowl, #24 in one piece to expose the float assy. I hosed everything out in there also. The only part I removed on the inside/underside of the carb there was #10 and hosed everything out real well. Then put everything back together.

Which parts need to come apart and cleaned well? I'm guessing I missed what needed to be cleaned.

Am I further ahead buying a new carb POLARIS CARBURETOR SPORTSMAN 90 CARB 2005 NEW! ?

 

LT80, I really want to thank you for your help with this also !

I appreciate it !

Steve B. & Family

 

Looks like a Dell Orto carb.
#10 indeed looks like the main jet. #8 (under #10) looks like it could be the pilot jet. It's a different type of set-up this carb is.
I wouldn't buy a new one yet.

 

(ETA: The carb does say mikuni on it I believe, I'll look again)

OK. I'm going to take it apart again right now and get another look. I'll post pics.

When I had #10 out I hosed it out really well as well as through #8. It didn't look like #8 was removable to me. Maybe it's pressed in..

I was thinking about trying to get to #21 and make sure thats clear. Maybe it isn't allowing enough fuel into the bowl causing it to bog down ? I don't know how much fuel passes through that opening under full throttle though..??

I just picked up another can of carb cleaner so here I go.......... again.


This may call for another post but how difficult is it to do a top end job on one of these to take care of the low compression ?


Thanks,

Steve

 

*Update*

I had the local shop look at the quad for me and I was told it needed a top end rebuild. I ordered the parts and on the way out the guy at the counter tells me to clean the spark arrestor while I've got it down. So I get home and take apart the tailpipe and the screen is 90% plugged with hard soot. I started the quad and it took right off. Still kinda sluggish but better than it's ran this year.
The next morning I call to cancel the order and he tells me it's too late, already ordered and there will be a 20% re-stocking fee. Ugh. Oh well, I guess I'm moving on with a new top end. I have it apart (that was easy) and can see the burning marks on the engine side of the piston where it's blowing by.

Can the cylinders be honed in these little bikes ? I had the service dept. look at it and they said it looks good but don't know if it can be lightly honed ? Something about the cylinder walls possibly being lined with something (nikelcadium or sumthin' ??)

Does this ring a bell to anyone ?

 

i just had to put new spark plugs in and my dads stayed running