Cold starting a trial, but instant when warm

I've almost got my 2 cylinder 55hp Mariner (made by Yamaha late 70s early 80s) water worthy. Today it took a bit to get started - starter pinion gear doesn't like meshing with the flywheel - but ran beautifully at idle and with some gentle throttle manipulation. Once it warmed up I turned it off and back on a few times. In the end I turned it off and let it sit for a while but decided to let it run until the fuel in the line was used, however I couldn't get it to start again. The battery (borrowed from the car, quite old too for a battery) seemed to be dropping with each new attempt but I was wondering if it might be something else that I've overlooked, any thoughts??

thanks in advance

Put a GOOD battery in it and might be all set.

Jeff

These things need a nice FAST cranking speed and the ignition/throttle sync just right to idle well, so if anything is out, they are cranky bastards to start!
I still haven't gone back and tried to get my one to run at a decent idle, it still wants to lose rpm and die below about 1000 rpm. Probably throttle opening too soon relative to spark I think.
I think they are so reliant on a fast cranking speed because they're a big bore twin, so need good airflow to get the relatively large reeds opening and closing nicely (ie, build compression).

Regards, Andrew.

The choke solenoid also needs a full 12 volts to pull in.

Jeff

Hi guys, I'm still at it too. Coinscedently, I readjusted all my throttle linkage this week-end to specs. I've had it on and off so many times, I guess, it got out of wack. In the tank, it seems to have helped with that up-and-down idle thing I had going on. I put that Loctite on the mix screw, like you said, and it changed the whole mix. I think, the screw was so loose(even seated it wiggled around)that it was sucking air.
I know that the 55hp's are in the next class up, but starting has never been an issue with my 40hp. I'm wondering if a better battery would throw that pinion up better. Also, do you have a lightening coil for charging? It may be bad.
Andrew, thanks for the insight on the reeds. I makes sense; At high speeds they would have no problem staying open, but, I can see how, at idle it could struggle to maintain an even opening. I checked mine out when I had it apart last, and none were stuck. I inserted the proper feeler gauge. None were open too far, but some were'nt open enough. I slid the gauge to the base (hoping to open them some), but I didn't mess with them too much, as I don't know how to adjust them. Could reed adjustment contribute to either of our problems? If so, how do you do it?

Reed valves are generally trouble free if not broken.----They ideally should lay flat on the reed block ( no opening ) with no light visible thru them.----They respond to pressure changes in the crankcase-------They have NOTHING to do with compression in the cylinder.

Reed valves (or any valve in any engine) has a LOT to do with dynamic compression, particularly at cranking speeds. If you have even small leaks, you're going to have a hell of a time moving air and creating a good crankcase seal.

Regards, Andrew.

Reed valves have to do with compression in the crankcase only ---------NOT the cylinder !!---------When you look at them in your hand it is preferred that you see no light , but slightly open ( up to 0.007" ) is deemed ok as per manuals.