New Conquest Engine Question - Could run smoother?

Carl in CT · Jun 3, 2011

My new Conquest has about 14 hours on it and the engine takes a minute or so to warm up and smooth out off choke. It runs strong but I notice the engine speed still seems to want to fluctuate slightly for a couple of seconds when coming out of a cut if the grass is a little high. It smoothes right out and it's very minor, maybe I'm just being picky because it's a new, expensive tractor.

I called the dealer and we thought there might be some build-up in the carb because it was a 2010 leftover with only a couple of hours om it so it did a fair amount of sitting around. He said to try some Sea Foam in the gas but if that didn't help he would be happy to look at it under warranty. He said he remembered this one being "cold-blooded" and always took a minute to warm up like I mentioned. I tried the Sea Foam through one tank and it's no different. I hate to drag it back to the dealer and have it gone for 1-2 weeks if it's nothing I should be worried about. The enigine is a Briggs and Stratton Vanguard 23hp v-twin. I did start using higher octane gas which also made no difference. Should I try more Sea Foam, or is there another remedy, should I bother dragging it back to the dealer just in case?

Am I being paranoid, should I just shut up and go mow my lawn?

Wolfy · Jun 5, 2011

I have poured SeaFoam directly into the carburater. Maybe 1 ounce or 2. It has worked well for me. While the tractor is idling, pour the SeaFoam in. It may take a minute to kick in. You'll know as white smoke will puff out until the SeaFoam gets burned off. It seems to clear out any residue from old gasoline. My dealer advised using Hi-Octane all the time, and after 2 years or so I can verify it does make a difference.

Carl in CT · Jun 7, 2011

I spoke to the dealer today and he is going to submit a warranty request to Simplicity to see if they will authorize him to put a new carb on it. If they won't he will clean out the carb for free and make sure it's running right. He seems like a good guy and I've heard good things about him and he promised he will make it right one way or another. That makes me feel better but I hope Simpicity will just warranty the carb, that would be the easiest I think. It's not running horrible so I can still mow my lawn, it's just not running quite like a brand new tractor should. I'll keep you posted.

Wolfy, if all else fails I will try your trick with the Sea Foam right into the carb, thanks for the tip.

mwb · Jun 8, 2011

IMO the seafoam added directly to the carb won't make any difference; this would only benefit carbon build up within the engine and not help with fuel supply / carb problems. if you have added it the the tank then that is the best chance that it will make a difference.

It sounds to me like it is running to lean; the fluctuating could also be caused by this or a minor govenor adjustment might be required. It probably just needs a slight tweaking. Stupid question but is the air filter installed? Maybe it was borrowed from the machine and never replaced. this would cause it to run lean.

Carl in CT · Sep 8, 2011

I have not checked the air filter but I will. I did bring it back to the dealer and he had his mechanic clean it out but it's no different. In fact, it almost seems like it starts a little harder. This makes me nervous to bring it back again. It fired up ok when I picked it up but he knew I was coming and had moved it out of the repair shop so it was still warm then. I will mow with it some more but it looks like I will be bringing it back again. Hopefully he will be able to warranty the carb and just replace it. At least that should eliminate that as the problem even if it doesn't fix it. It does seem like perhaps a governor tweak might be in order but I hate to start monkeying around with that already. It's a great mower overall and I think the engine is fine but it's just too new for me to settle for it being less than perfect without at least speaking up while it's still under warranty.