Taming The beast

SRX 540 · Post by **SRX 540** » Sun Jan 03, 2010 12:53 pm

OK The Klingons who had it before me ran it like it was the General Lee-Rode hard and put away wet!

SRX 540 · Post by **SRX 540** » Fri Jan 15, 2010 6:55 pm

Alrighty, got my brand new VM 38s in and she actually runs decent.!!! One thing.It's hard to start up.You have to flutter the gas to get it running but once it's idling you're fine.If you shut down it's the sam all over again. The Mag side is running colder(rich) I don't have a way to Measure EGTs. The carbs are Jetted the same(360, non power jets) How could I even them out? Plat with the needle height or change Jet size?

Post by **Vmax540** » Fri Jan 15, 2010 7:20 pm

360's seem rich even for non power jet carbs. The best of course as you mentioned is EGT gauges and the second best is reading your piston tops for correct wash after a high speed ~1/4-1/2 mile run. The way I was told is you should have a quarter sized clean spot on the transfer port sides of the piston and see a light carbon deposit on the rest of the piston top. Basically, a rich enough A/F mixture will wash the deposits away from the transfer port area. Anyone (Bob ect...) have a better way or description please chime in !

SRX 540 · Post by **SRX 540** » Fri Jan 15, 2010 8:44 pm

the pot plug seems to be a bit lean,neither plug is gold. One is whitish and one is blackish.The plugs are fresh and I went for about a 1/2 mile run. It really runs nice once it's going. Lots of snap.EGTs seem to have evened out.Used a lazer thermometer on the pipes,Not a perfect way but better than burning my hand. 189 degrees + - .Flipped the choke half way on and died instantly.Hard to start up again.

SRX 540 · Post by **SRX 540** » Fri Jan 15, 2010 9:58 pm

pto** not pot

SRX 540 · Post by **SRX 540** » Fri Jan 15, 2010 10:05 pm

One thing I never thought of.. could wonky pipes be a problem? I have some AAens on there.Maybe some shit inside one of them would cause my rich/lean woes?

Bob Vehring · Post by **Bob Vehring** » Sat Jan 16, 2010 12:11 am

I thought I would have better answers by now. My carbs are a mess and really don't respond well to changes I made. It was very lean low and mid, main jet change wouldn't richen it unless I picked up the needles. Been through that before, just means needle or Needle jet isn't right. I got temps down but now it has no power on the bottom, I mean NO power. I also have to have a one step stagier on the needle to keep temps even.

I had the 39.5's taper bored on my SRV, seems to like them so I had a set done for the VM they should have showed up 2 days ago, Today I got an email from Fed X saying they had been delivered yesterday. Ya gotta love those guys, They hide the box so nobody steals it, but they don't tell you where. I found them tonight, hidden in the ft yard. Next week I going to plug the PJ and set them up like my SRV carbs.
I'm taking a couple of my old sleds to a vintage show tomorrow, I'll take the VM along and maybe play with the carbs it has for a while.
Been warm here for last 4 days, and getting warmer next week...........

SRX 540 · Post by **SRX 540** » Fri Feb 26, 2010 7:27 pm

OK, new updates. Git some Stock pipes and can. Runs a lot nicer. Both plugs are gold.But the PTO is still running hot. Still kinda hard to start.Have to flutter he gas to get it going. Lazer thermometer on the pipe says 270 on the PTO and 170 on the mag. IS this just a fool around with jetting and make sure throttle cables are even and the chokes are the same issue

Bob Vehring · Post by **Bob Vehring** » Sat Feb 27, 2010 2:46 am

Measuring the heat at an idle really doesnt mean anything. Most likely its telling you one slide is open more then the other at idle. I have one of those vacuum set up tools for syncing the carbs, I never use it because it really doesn't mater to me. The engine won't make any heat until it works hard, you need to find a way to measure at speed under load to find out whats happening inside.

SRX 540 · Post by **SRX 540** » Sat Feb 27, 2010 6:38 pm

So it may not be that there is anything wrong just that a carb is open more. Or it could still be trouble.

Bob Vehring · Post by **Bob Vehring** » Sat Feb 27, 2010 11:47 pm

can't answer that I don't know the sled. Reading pipe temp at an idle will only tell whats happening at an idle and it only tells the temp as it has heat soaked the pipe. Yes having one carb slightly open more at idle could account for the temp difference, so could jetting being off either through a bad choice in jets, or something plugged up in one of the circuits.
EGT gauges are the practical way to monitor the temps not only through out the rpm range, but also at different throtle positions (part throttle).
You can find used EGT gauges sometimes cheap on ebay, new cost 150-250, still cheaper then a burndown