Engine bog - Snowmobile Forum: Your #1 Snowmobile Forum

crispyzombie · 01-24-2013, 07:04 PM

On my 76 panther 5000 when i give it lots of throttle the engine will bog and refuse to accelerate, but after a couple seconds it picks up and starts going.
Setting the carb richer or leaner seems to have no effect. I have also cleaned the carb and put new spark plugs in.

I am quite new to this stuff so any ideas of what I should try will be appreciated
Thanks

**kccats** · 01-24-2013, 07:08 PM

Have you cleaned the carbs? Done a compresion test?

crispyzombie · 01-24-2013, 08:50 PM

The carb has been cleaned and the compression is good. Also the higher the rpm the better it gets.

Josh Kidner · 01-24-2013, 09:15 PM

Does it have the stock airbox? Sometimes hot air can cause issues when it gets sucked in. Alo double check your pilot jets to make sure they are 100% clean, how much smoke are you getting at idle- 1/4 throttle?

crispyzombie · 01-24-2013, 10:04 PM

I am currently running it without an air box and at idle it is a little smokey. I didn't think that warm air from the engine would make that much of a difference, but I'll give the air box a try next chance i get.

Josh Kidner · 01-24-2013, 10:34 PM

Quote:

Originally Posted by crispyzombie

I am currently running it without an air box and at idle it is a little smokey. I didn't think that warm air from the engine would make that much of a difference, but I'll give the air box a try next chance i get.

It really shouldnt cause much of a difference, but hey, at least you can rule it out, as it is a factor

**kccats** · 01-25-2013, 06:30 AM

You really want an air box, that is a piston port motor and it will spit gas out of the carbs!
When you cleaned the carbs did you floss the pilot jets?? (up the tube)
It may be that it may need to be jetted down or the center to center on the clutches is off?(10 1/4")

crispyzombie · 01-25-2013, 05:20 PM

Today I put on the air box and cleaned up the clutch. When i took it for a spin it does the same thing, kinda boggs/sputters when i give it lots of gas. It starts bogging when i get to about 1/4-1/3 throttle. Once it finally revs up and i keep it in higher rpms it responds well. It also boggs more when it has a load on it such as going up a hill.

Also the carb was cleaned with solvent and compressed air so it should be good

edge800ves · 01-25-2013, 06:32 PM

Id bet on a choke being the problem, did you pull them out and clean em with the carb?

**RJ Gleason** · 01-26-2013, 04:55 AM

Have you cleaned and serviced the clutches?

**kccats** · 01-26-2013, 07:42 AM

The reason we keep asking about the clutches, is most bogs are clutch related!
I know we are talking about a Vintage sled, but the same things apply! Start by cleaning the surfaces with a scotch bright or sand paper, then blow them out reall good! Then measure the centers with a tape mesure! Next take a carpenters square and go across the spark plugs to the driven clutch!If anything you want the engine to be just forword of center on the clutch side, so that under load it is square!

crispyzombie · 01-26-2013, 02:09 PM

I cleaned up my secondary clutch today and now the machine runs much nicer. When i give it throttle now it will only hesitate/bog for a second then immediately open ups, a major improvement

The engine is sitting ahead of the clutch so no problems there. Also what do i measure on the clutches to see if they are not centered?
Thanks so far!

Also what fuel-oil mixture should i be using? It says 20:1 on my sleds hood but that seems very rich

**RJ Gleason** · 01-26-2013, 04:32 PM

You can safely mix 40:1 with the modern oils.
That will probably help with the remaining hesitation.

**kccats** · 01-27-2013, 06:46 AM

Mesure from the center of both clutches!

crispyzombie · 01-27-2013, 07:02 PM

As far as i can tell the clutches are centered and I tried less oil in the fuel and its still the same. Also in deep snow the track will not spin and the engine stays in a low rpm, so this would indicate a clutch problem?

Josh Kidner · 01-27-2013, 08:23 PM

Quote:

Originally Posted by crispyzombie

As far as i can tell the clutches are centered and I tried less oil in the fuel and its still the same. Also in deep snow the track will not spin and the engine stays in a low rpm, so this would indicate a clutch problem?

Could be broke secondary spring. If its not downshifting correctly it would be boggy until you get going as it would be like driving a car and taking off in 4th gear.

**kccats** · 01-27-2013, 08:46 PM

Did you actually mesure the center to centers? And that it is Square?

crispyzombie · 01-30-2013, 10:07 PM

I gave my secondary clutch a proper cleaning, sanded off the rust, cleaned it till every last bit shined. Now the bog is almost completely gone

Can't believe i didn't do this in the first place

had no idea the clutch could cause that much bog!

Also i have no idea about this centering clutches business, from what i understand it is that the clutches are aligned properly?

Now i have to hunt down whats causing my last bit of bog.. will not stop till its perfect!

Thanks!

**RJ Gleason** · 01-31-2013, 06:53 AM

Do the same for the primary too.

crispyzombie · 01-31-2013, 02:29 PM

Ok now i have another problem, i just check my spark plugs, one is all black (rich) but the other is white and is lean, but there is only a single carb

what could be causing this?

oh and heres a pic after about 20 mins of riding

the one on the left is bone dry, do you think its too lean?