'86 Vmax Carbs

[Donnie]

I had this on the last forum, but I thought I would put it here too. There was one reply to my question about the brass posts on the carbs on the '86 Vmax. There are actually 3 posts in question here. I will seperate them into two questions.

There is one post on the left side of the intake side of the carb, not the airbox side. It is very small. It is the same size as the oil line coming from the oil pump and as luck would have it, cut to the correct length to fit it. I have the oil line hooked into that post at this time and oil is definately flowing from that into the carb and hence into the engine. So the question is... DOES the oil line get hooked to the post? Just for the record, I am NOT talking about the posts that are on the cylinders which have the rubber caps and clamps.

I noticed that the fuel routing is totally different than that of my '83 Vmax where the oil mizes with the fuel near the gas shut off valves behind the radiator. The '86 DOES NOT have fuel shut offs.

Part two... there are TWO large brass posts just behind (as viewed from the seat of the sled in riding position) the choke (enrichment valve) cable on the right side of the carb that look as if they have never been hooked to anything. Any suggestions???

Does anyone have a picture of the carb setup from a running '86 Vmax that they can send me or post? I obviously don't want to torch the new parts I just put in this sled. How about a '86 / '87 service manual with hose routing diagrams?

Thanks everyone.

Donnie

[Donnie]

I took photos and detailed them so that the parts in question are easy to identify. Please reply soon as I want to go ride this thing and I don't want to blow it up. Thanks

Donnie



Visit http://infinitefx.com/vmax for more pictures. Thanks

[Guest]

The two larger ports on your carbs, the two next to one another are coolant ports for heating the carbs. One of the lines will come from somewhere close to where your radiator cap is located, the other will come from someplace close to the thermostat housing, and finally the two remaining ports are tied together between the carbs. Hope you understand what I'm trying to tell you!

The oil lines coming from your oil pump should tie into the fuel line on the fuel pump inlet side. It should have a fitting in the fuel line with two male plug receptacles protruding outward on the inlet side and you plug your lines into these and this is how your oil is mixed with your fuel and pumped up to your carbs. You must bleed your oil lines to be sure there is no air in them before installing them. The easiest way to find your fuel pump, not sure on your machine, but on my Exciter it's located under the airbox and you have to remove the secondary clutch, then the airbox to get to it and then its easy to plug the lines in and check everything out! Hope I've been some help and good luck!

[Phil peterson (opsled)]

Hi Don, The previous post is correct in that the big ports to the rear of the choke plunger are for engine coolant to pass through. The coolant heats the carbs in very cold temps to prevent icing and burn down. They had an on off valve under the hood and you would only turn them on when temps were very cold. The problem is that they were not used on the 540 V-max and the small ports you have your oil lines attached to is proof. Those carbs are off of an Exciter 570. Those small ports are to hook up a carb sincronizer gauge. The V-max has them on the cylinders and the Exciter had them on the carbs. Those small ports should have the little black rubber caps on them like the ones on your cylinders. Someone has replaced the stock carbs with those and rerouted the oil lines to those ports. An 86 V-max should have oil line T's and fuel shutoff valves in the same place as an 83 V-max would but the valves are a different style. They were cable operated from the dash with a lever assembly that looked similar to the choke lever and was mounted right above the temp gauge. The early 83-84 manual valves worked better and didn't break as often. There are numbers on the front side of the carbs below where the choke plunger goes in. The first 3 digits should match the first three digits in the engine and chassie #'s if you have a #'s matching sled. The last three #'s on the carbs will be 00L and 00R to designate right and left. The #'s on the carbs for an 86 V'max should be 81K-00L (left) and 81K-00R (right). If you give the #'s off the carbs on your sled to a dealer I'm sure he will tell you they are off a 570 Exciter.

[Vmax540]

I agree with Phil 100% Exciter carbs ! I have Bender Racing direct oil injection kits on all my sleds that used Yamaha's questiionable setup of injecting the oil before the carbs into the fuel lines. I have always had good luck with this setup and have wondered why one could not use the sync. vaccum ports to hook the oil lines to ? Maybe Benders small orffice nozzles spray a fine more evenly spread oil pattern ?

[Phil Peterson (opsled)]

Oil injection systems don't have enough preasure to spray they just drip. The problem with most sync ports is that they are on top of the manifold or carb so they are easy to get to, while oil oil injection ports are usually on the bottom so they stay full of oil and don't bleed down when the engine is just sitting. If you use a top sync port for your oil injection try not to have to much of a loop in it as the oil from the highest point in the loop down to the port can bleed off into the manifold causing a very smoky startup when the engine is next fired and then a lag time for the oil pump to catch up again. I've restored a few 540s and with new fuel and oil lines you can watch the oil entering the fuel lines. At idle its a slow drip and as the speed increases so does the drip.I've never had any trouble with injecting into the fuel lines but I will also usaully increase the flow by lenghtening the oil pump cable an 1/8 or so beyond factory specs just to be safe. I've also seen some turn theirs back because it smokes to much which isn't always a good way of telling as some oils will smoke more than others and some not at all. Oil is critical but most engines go down because of lack of fuel not oil.
Good Luck, Phil

[Donnie]

Thanks to everyone for the replies, this now leads me to more of a problem then. I should get the setup needed to feed oil directly into the fuel lines since having oil dropped in through the carb is not correct. So I need everyone to go through their box of goodies that you have and find me an '83 or '84 Vmax fuel shutoff and T fittings. Or, if someone has the original type with the line that goes through the dash, I will use that. I do have an extra set of carbs that I can use, which are from an '84 Vmax. So please, help me get the parts I need to get everything back together and safely running. I don't have enough spare parts to do it on my own. Thanks for everything.

Donnie

[Phil Peterson (opsled)]

Hi Donnie, I went through my parts and I only have one good valve with the bracket and cable. If I keep it I'll probably never need it. If I part with it I'll need it in a week. Why don't you give me a call at 262-767-9023 maby you can talk me out of it.
On the tee's I would buy new from Yamaha last I checked they were still available and they tend to get brittle with age. The last thing you want is a burned up engine because of a cracked $4 piece of plastic. I would also buy new fuel and oil line from Yamaha it fits better, lasts longer and the OEM clamps will work on it.
Good Luck Phil