360 Chrysler running like crap cont...

[bill]

This is a continuation of my write up from the old site..
After changing filters, spark plugs, wires, rebuilding distributors, rebuilding carburetors, cleaning flame arrestor and new coils on both engines. The missing under load returned. It was time to get some professional help. Thank You Ron S.

First he looked at the port engine. After I got it started, which by the way was always a problem. He committed that the timing was off which he verified with the timing light.
Adjusted timing to specs. He then went on to the carb. After pulling the flame arrestor he notices the choke is half on while the engine is up to normal operating temp. He made an adjustment to the rod that connects the choke linkage to the thermostat controlled pull down spring
and then adjusted the two low speed idle adjusting screws using a tachometer. Set the idle speed at 750 rpm. Shut the engine off and restarted it. It started on the first crank. Usually it takes three or four revolutions to start. We take it out for a test run. Runs great
We notice that the port throttle handles and the starboard throttle handles are not even. Port is half way open and starboard is all the way to the wall. Head back home and make a date to look at starboard engine.

Onto the starboard engine He first checked the timing, it was spot on. Next he took a look at the carburetor. Removed the flame arrestor and found that this choke was working perfectly. Did a the low speed adjustment on the carb and set the idle to 750 rpm. After reinstalling the flame arrestor I notice that the bracket on the flame arrestor that I had made up for the fuel pump diaphragm rupture syphon hose was sitting right on top of the choke linkage keeping the choke practically closed. What a dufass!
Took the boat out for a test run.. OMG I have died and went to heaven
Both engine are running as they should. Took it up to wide open throttle and both engines were reading 3400 rpm with the throttle to the wall and she jumped up on plane.
A very special thank you to Ron S. and his son Eric.
bill

[jtalberts]

Great to hear! Wish I could find some local people to help with some prop shaft work.

[barkleydave]

=150]Great Post Bill !

Nice approach to find minor glitches which can result in poor performance.
[size
Amazing you are getting 4200 at WOT

Going to re-check my carb and choke settings. I know my timing is correct due to the recent Distrib test but will certainly recheck.

[/size]Safe Boating,

dave

[Fastjeff]

One hell of a good mechanic there! We have one at our slip as well, a cracker jack kid named Evan.

Jeff

[bill]

Took the family out for a day on the water. Everything great for about two hours. Cruising along at 1500 rpm. then Mr. Port started missing. I slowed down and put both engines in neutral. Goosed Port engine and it sounded ok. Put both back into foreword gear and port stalled. Did I mention I was in the shipping channel and a large lake freight was getting to close for my comfort I managed to get out of his way. and headed back home on the starboard engine. Thank goodness for twins

Called Ron and we set up an appointment to meet at the boat. We took it out for a run and sure enough after a couple of hours
we were able to recreate the problem. we limped back to my dock on the starboard engine.

I replaced the fuel lines from the shut off valves to the fuel pumps. rechecked the float setting on the carbs, added
Mr. Gasket #97 Isolators between the carbs and intake manifolds and installed fuel gages on both engines between the carbs and fuel filters.
The thinking here is vapor lock. Now to take all my empty beer cans in for my ten cent depost hoping there is a $1,000.00 dollars worth because that what it will take to fill both tanks. I know Docsnow has a lot more of the empties than I do,
maybe he could help out a fellow boater.
bill

[bill]

Well it only took 8,000 empty beer cans to fill her up.
(.10 x 8000 = $800.) Thanks Doc.
Well next week we are back at the problem of the engines running like crap.
Hoping to get it all straighten out before I haul it out for the long winter.
We have a list of things to check.
bill

[Roger2]

Just a thought. Coil breaking down after heating up?

Roger

[bill]

Well that's what I figured last year. Replaced both coils. Same problem. Also ran a heat check and voltage check after running for a couple of hours. The magic number appears to be two hours of running. I now have pressure gauges at the carbs and volt meter at the ballast resistor and dwell meter at the neg terminal on the coil. Going to run another set of tests tuesday.
Stay tuned
bill

[Supersport18]

Bill,
I experienced a similar problem with my port engine. After running for an hour it would start missing and wouldn't run past 2200 rpm. Didn't stall, just wouldn't power past 2200.Turned out to be condensation under distributor cap. I suspect that as engine warms up internal condensation tries to find a way out and collects under distributor cap. Might be worth a look see. Good luck.

[bill]

Thanks I will be checking on that also..TODAY!!
bill