Just bought a 98 summit 670x, the last owner just had the carbs rebuilt twice and replaced the coil and tether key. Its real hard to start, any idea whats causing it to flood ? Runs great when it gets going just hard to start 20+ pulls. It also has new plugs, and it gets spark. The primer seems to be leaking just a little bit at the top.
98 670x hard to start help!
- Thread starter reaper020
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99summitx
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Are you sure it's flooding ? if for sure try shutting gas off at petcock before killing engine, it a pain but it helps, also try to have the frontend higher than the back end when you park. When you say carbs rebuild were the needle and seats replaced.
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I believe so I just talk to the repair shop on the phone today I am going to go in and ask the repair guy more questions. Its deffinatley flooding the plugs are wet if it doesn't start right away. sometimes i get lucky playing with the throttle when starting. but once its warm takes tons of pulls to get it going. the last owner just spent over 700$ on the carbs, or carbs and coil and tether. not sure he said just the carbs but seems like alot.
Can the primer cause flooding or is there any way to test the dpm. thanks for the reply this is my first time using a forum. I will try shutting off the fuel next time its running.
Can the primer cause flooding or is there any way to test the dpm. thanks for the reply this is my first time using a forum. I will try shutting off the fuel next time its running.
mountainman611
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Had a 97,had to be easy on the primer (when cold) and if its flooded hold the throttle to the bar,should start in a couple of pulls.
99summitx
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Yes have to agree with the others on the WOT when starting, I never prime mine more than 2-3 times when cold and then once its been warmed up maybe 1 pump if it been sitting for more than 5 min otherwise it doesn't need it.
99summitx
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Oh yeah I pm,d you back.
Go-Vertical
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Think there was a message about float levels from brp. Think it was just an ajustment issue. they were set to high, seat would't close when was level or pointing down hill. Maybe phone specialty talk to ken or eric.
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Also there was a change in the spark plug gap, other than what the factory originally came out with..... Think original gap was .018" and they increase it to .020"?? Can't quite remember now, anyone else know??
Yep, this is what I was thinking. Float levels set too high will make it hard to start and will bog when going downhill.
If its hard to start when its hot, you should do a compression test. This is often a sign that the rings need to be replaced.....
Mine started this year on the second pull after sitting all summer, they will usually start by the third pull.
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yup, mine too...
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It took me a while to figure out the proper routine but mine was 3 primes and 3 pulls to start. Worked nearly every time.
I also placed my fuel shut off valve on the dash so I could easily shut it off the fuel when it's upside down. If you think it's tough to start now, wait until you tip it over for a few minutes....50 pulls....
I also placed my fuel shut off valve on the dash so I could easily shut it off the fuel when it's upside down. If you think it's tough to start now, wait until you tip it over for a few minutes....50 pulls....
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or just stuck pointing uphilll.... Hard to start after getting it down.... Need to hold partial throttle to start then....
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I was thinking of relocating the fuel switch to. I got it running good now cold. i left the fuel on to see if its leaking into the carb if its flooded in a half hour then its leaking in. was hard to start this morning plugs were fouled . So I cleaned them up and 8-10 pulls later it fired up. Im thinking it may be the dpm or a leaking primer any thoughts on? I forgot to mention that it doesn't bog at all when running and it idles fine just seems flooded when starting warm?
The primer is a plunger type, they either work or not. Doubt it is the plunger not sure how it could be leaking unless there is an air leak in it that is allowing the fuel to drain out of the pressure line to the carbs. If it had a bad air leak it won't work because it would suck air instead of fuel on the suction line (the one that "T"'s off the main fuel line going to the pump). They are a cheap replacement so its worth a try, but usually when the internal seal fails, they just won't pump anymore because all they do is suck air.
DPM could be a problem, check all lines for cracks etc and see if any are broken. You could find another DPM and see if it works, its just a simple plug in test.
I still say do a compression test. This will confirm or eliminate the possibility of low compression. Hard starting when hot is a strong sign of low compression usually. With low comp it will still run like a champ so sometimes it can be deceptive. Ifthe comp is good, then at least you've eliminated one possibility.
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My dad's Summit 600 did this exact thing. Really hard starting once warm, starts great when cold and runs like a champ all the time. Its a newer 600 and the rings started flaking the chrome off. Compression was down to about 80 PSI in PTO side. Just needs new pistons and rings, not a total rebuild. Pistons for the 670 are about $85 each for SPI's and a total gasket set is $85. Once its apart you can measure rod deflection and crank run out and determine if you need a crank or not. They are about $500 out of Quebec. Total rebuild for a crank, new pistons, gaskets, etc set my buddy back $800 on his 800 Highmark this spring. Pretty cheap overall. You may not need to rebuild it, the cause might not be low compression at all. But if you test that and it is OK, then it rules out that possibility. After that, it almost has to be the carbs if it is getting good spark when hot.
How many miles on the motor?
The primer is really easy to diagnose too. Start it up, let it warm up and then shut it off. Try to start it again. If its hard to start, pull the primer line off each carb, let it sit for 10 mins or whatever it usually takes to make it hard starting and then try and start it again. If its a leaking primer, it should start up no problem with the primer lines pulled off. If it still is hard to start, then its not the primer.
If you want to see if its the floats, jack the front of the sled up after you warm it up. Lift the front of the sled so that the skis are about 6-8 inches off the ground. Make sure the sled is secure and then try and start it. Just don't jack it up and pull the primer lines off at the same time. If the primer thing doesn't work, then try the jack. Don't do two things at once, only try to diagnose one problem at a time.
Then I would try the DPM. This will eliminate one potential at a time.
If that doesn't work, you are going to have to pull the carbs and see what jets are in them I guess.
clint/KTM/16
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guy at rech tec told me after ur done riding(for at least a day or done for the night)., prime 2-3 times. then next time you go riding should start 1-3 pulls. it'll help you start to begin with but sorry for no help on starting when warm... same thing happens to my buddy's 583
Rucky
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Fuel shut off for roll overs is a great idea. My cousins 670 easily took over 100 pulls (no exaggeration) after lying on it's side for about a minute while shut off too. Finicky set up and a real pain in the ars. 
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