Wiring 1979 Chrysler 100hp to Yamaha Tach?

[JoshJK]

wot timing is at about 36-37 degrees. Timing belt does seem just a little loose but not bad

 

[JoshJK]

Confirmed spark on all cylinders also, but have no idea how to make sure I have spark under load.

 

[JoshJK]

I just redid a compression check again with the engine warm this time. All cylinders were 140-142. I am not sure what could be an issue here if I have good compression and good spark and no fuel delivery issue. The lower carb is ever so slightly not quite to fully horizontal position at wot, but it is VERY VERY close. Close enough to not mess with I think. I just got done setting the timing to 32 degrees instead of 37 where it was. Is this going to make a difference?

 

[JoshJK]

I do get some fuel runnin out of the front of the carbs, even with the engine not tilted up. Could this mean I have an over fueling issue?

 

[JoshJK]

I just made a video of the engine running. The engine does change/run rough when each of the spark plug wires are pulled off. It does seem to run pretty rough to me. You should be able to see how wet the carbs are in the video. I ran the engine with the prop off, in gear with ear muffs on up to around 3000rpm and not sure if it is running right. Again, I have confirmed spark and timing along with good compression. I will post a link to the video here as soon as it is uploaded.

 

[JoshJK]

http://youtu.be/xI6eWTD1zxA

 

[JoshJK]

one more thing to mention would be that this engine is now installed on a boat with an onboard gas tank under the floor. the previous engine was oil injection so there was no oil in the gas tank. When I put this engine on the boat, I pumped the gas tank out as best I could and then refilled the gas tank with 40:1 mixture just to be safe incase there was still a little bit of straight gas in the tank. Would running a richer mixture of oil make the engine run worse?

 

[JoshJK]

anyone make anything out of this new info and video?

 

[MickLovin]

If your tacho is correct, and I suggest it isn't, your idle is too low in neutral. it should be around 1000 - 1100 rpm in neutral and it will reduce down to 750rpm when put into gear (IN THE WATER) it is harder to tune these without exhaust back pressure. Are you using surface gap plugs either ngkBUHW or Champions equivalent. What do your plugs look like when you pull them out, are they tanned or are the black with oily residue?
I have this exact motor, the carbies do leak a bit, that is there nature, but a good overhaul of them is not hard to do if you have the kit and compressed air.
If you have done a link and sync as per Frank Acampora's video or tutorial I think you need to check a couple of things.
My opinion I wouldn't be revving the engine that hard without being in the water so it has some load on it, a big tank of water is preferable to muffs but better in the river etc.
What do you have your carbies set at?

 

[Nordin]

Hard to say if it is running okey in the video, retarding the timing from about 37 to 30 BTDC will affect the performance as it is now overtimed.
Have you checked the reedvalves? If some pedals is bad you will get fuel pushed back in the carbthroat BUT it can be normal that fuel is visible in the throat.

 

[JoshJK]

I know little to nothing about reed valves, but do you think that that could be my issue. Boat is in storage now and have some time to tinker with it(although not go to the lake and test). Would it be worth it to just go ahead and buy new reed valves and replace them?

Maybe also swap to the 125 carbs(if those were the ones Frank mention, cant remember exactly)

 

[MickLovin]

Frank advised me to change my carbs from the WB carbs to a TC carb which you can obtain from a 115HP up I believe, only difference will be the jetting of each hp carb over 115. I obtained a set of TC carbs from a 140hp but you will also need the flange they mount to as the flanges aren't the same from a 100hp wb carb set up. You will also more than likely need new gaskets for the flanges and the carbs.
I did get a bit more HP from my 100hp motor, say 1-2 MPH @ WOT, but they leaked no differently to the original WB carb. I wouldn't think it is your reeds but they aren't hard to check either, just obtain some spare gaskets or have some gasket material available before you start pulling the carb set up apart.
Keep checking your spark plugs, they are the biggest indicator of what is happening with your motor. Your timing on the 100HP should be 32 deg, I also have the manual for the 100hp Chrysler which shows you the complete way to set-up fuel,electrical and compression tests and specifications.