Hi guys, as you can see I am new here but I have done a lot reading and learning from you guys. I really need someone's help with this new predator 212 project that I have been working on. I have put this motor in my sons snowmobile and it is extremely hard starting. So much that I almost broke my thumb when it kicks back and I has kicked back numerous times. This motor is new but I started modding it before I installed it. This is where I think I have issues. Here are the mods that I have done to the motor. Governor removed, arc aluminum flywheel, 18 lb valve springs, lash has been triple checked to .003 on both sides. 140 emulsion tube and a 36 main jet. When I do get it started The spark plug indicates that it is running rich. Please help before I break hand.
Extremely hard starting predator
It is a Hemi style predator. The plug indicates a really rich mixture. I am going to start drilling the stock jet to get it dialed in once i figure out what the hell is causing this thing to rip my arm & hand off. When i set the valve lash i noticed that the compression relieve was working on the exhaust valve. I called ARC today and explained everything to them to see if they could help and they recommended that i try and retard the timing with a new flywheel key and just flip it around to retartd that timing. ??????
I will inspect the cord retractor tonight when i get home. I spoke with ARC and they mentioned that the 32degrees of timeing maybe the culprit so i may retard the timing. On the flip side of that i called another guys and he mentioned that i should be able to run 32degrees of timing without any issues at all and that my problem is most likely the compression release on the cam. So i pulled the motor our of the snowmobile, pulled the cam out and inspected the compression release. It didnt appear to be hanging up and appeared to be making contact with the lifter. I read a post that mention that the compression release tab can be bent a bit to help it out so i bent it up to ensure that it is making enough contact with the lifter. Put the cam back in and adjusted the valve lash to .002 on the intake and .003 on the exhaust. I also found that my dumbass put not one but two carburator gaskets on backwards upside down. I am sure this didnt help my starting issues. Do guys have any other suggestions?
I have almost the same set-up, but I have a .035 main jet.
Did you set the coil gap after you installed the billet flywheel? Should be .030
My other thought is the tightening procedures/specs for the cover bolts. If not,
this could be binding up your crank/bearings.
http://www.oldminibikes.com/forum/honda-clone-predator-engines/27784-honda-clone-5-5-6-5-hp-bolt-size-torque-specs.html
Take the plug out and pull it a few times to check, you can check your recoil here too.
You haven't really done anything to warrant a timing adjustment, it should be fine.
But with the new carb jets and springs, you do need a good aftermarket air filter
and exhaust header. It could be running rich because it's not getting enough air.
It needs to breath...Mine runs a little rich too... Let's just get yours running.
Did you set the coil gap after you installed the billet flywheel? Should be .030
My other thought is the tightening procedures/specs for the cover bolts. If not,
this could be binding up your crank/bearings.
http://www.oldminibikes.com/forum/honda-clone-predator-engines/27784-honda-clone-5-5-6-5-hp-bolt-size-torque-specs.html
Take the plug out and pull it a few times to check, you can check your recoil here too.
You haven't really done anything to warrant a timing adjustment, it should be fine.
But with the new carb jets and springs, you do need a good aftermarket air filter
and exhaust header. It could be running rich because it's not getting enough air.
It needs to breath...Mine runs a little rich too... Let's just get yours running.
Ok. I pulled the motor back out of the snowmobile and then tore the side cover back off to ensure that my timing marks on my cam and crank lined up. They were good. I then checked my valve lash. Here is where I think problem was. My valve lash was at .006 for the exhaust and .005 for the I take. I set the intake at .002 and the exhaust at .003. I turned the motor over several times and rechecked the lash. Good to go there. I then checked my coil gap. Possible issue here also. Coil gap wasn't even close to .030. Fixed that and rechecked it. I also made sure that my flywheel key was in good shape. Good to go there. The. I build a test stand which is what I should have done from the start. I started the motor up with no issues and started taking plug readings. With the 36 jet I was way to rich and the motor is breaking up in the mid and high rpms. I am also noticing surges of air coming back through the carburator and mid and high rpms. Is it back firing through the carb? Don't what to about this problem. I am not sure what could cause air to go backwards through the carb. Please help.
They "pulse" through the intake too (that's how you can run a fuel pump from the intake side) so that's probably nothing to be concerned about. You will not be able to read the plug if it idles, they have got to run rich at idle to have good power in the mid range (no accel pump). Remember, the 140 Etube has less/smaller holes, so it will need less jet. If you have it, I would put the original etube back in and try the 36 jet. But , you need a load on it to really see if its performing good. I set the lash as close to zero as possible cold, and it opens up when running.
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Ok I put the engine back in the snowmobile so that I could have a load on it. I even bought a new NGk plug. Started it back up and it start up great and idles great but it is breaking up badly in the mod and high range. Pulled the plug and it is black on the porcelain. I guess I am still rich. Later tonight I am going to put the original etube in and try it out again. On the only bright side I have fixed the pull cord ripping out of my hands and it starts right up.
Yes, but
There are a lot of things that "could" cause sputter. I was puzzled by a B&S lawnmower
that would rev, quit, rev, quit etc. while cutting grass, but was fine while idling.
No adjustments on this 2.5hp carb. Turns out the diaphragm that sucks gas from
the tank was bad. Replacing it, a carb cleaning and a fresh tank of gas solved that problem.
Try a few things with the stock parts in first.
Maybe it's just a bad plug, or a crimp in the fuel line. Search n destroy the possible causes,
starting with the most basic #1) is it bad gas? :hammer:
There are a lot of things that "could" cause sputter. I was puzzled by a B&S lawnmower
that would rev, quit, rev, quit etc. while cutting grass, but was fine while idling.
No adjustments on this 2.5hp carb. Turns out the diaphragm that sucks gas from
the tank was bad. Replacing it, a carb cleaning and a fresh tank of gas solved that problem.
Try a few things with the stock parts in first.
Maybe it's just a bad plug, or a crimp in the fuel line. Search n destroy the possible causes,
starting with the most basic #1) is it bad gas? :hammer:
Here is an update on my project motor which shouldnt have been a project. I pulled the main jet from my gx120 and drilled it out to .028 and installed it with the 140 etube. I also installed the gx120 air box with no element on motor. Wouldnt you no it got a lot better but i am still a little rich according to my plug reading. Tonight i am going to try the k&n style filter and see if it gets even better.
Yeah i am sure it may somewhat restrictive but i figured out that i can run the K&N style filter due to space. The motor is in a snowmobile and space is limited but i am going to try and fabricate a piece to try and it work. I think i have to if ia m going to get the most out of this motor. We did however take it out yesterday and thing ran like a champ! That little sled aven pulled my fat ass around. I was impressed with the torque but the trottle response could have been better. However it build RPM's. I will continue to work on it and keep everyone posted.
After my last post i have taken the restrictive air box off of the sled and rejetted it. The reason for rejetting is that i feel that the motor has more to offer and the jets that in there were .024 pilot jet (way to big) and a .028 main jet. Plug readings looked good but i felt that i had it running better before i put the carb gaskets on wrong, had an incorrect valve lash settings and before i started drilling out the pilot jet. This has been a learning experience to say the least. A lot of my errors have been made by not being patient and not understanding how important even the little things are to get these motors to run right. So now my jets are .016 for the pilot and .035 for the main. I also have the 140 etube installed. The throttle respons is extremely better but since i dont have the K&N style filter on it because i need to fabricate it to fit i am now lean on my pulg reading and it is breaking up in the higher rmps. Now i think if i get the filter on there it will richen it up a bit to get a good plug reading. If not i have a .036 & .037 jets to go to.
