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Re: Stalling Port engine
Posted: August 18th, 2017, 4:43 pm
by bud37
km1125 wrote:Source of the post The two that I feel were good tests were 4% and 5%. The third I did was 14%, but I'm not sure that was even at TDC.
Nice numbers....geez I had fresh race engines that were higher than that and they were 700 HP ( big piston to wall though).....I always had good luck with one plug out at a time and putting the power bar on the crank nut and against something to help stop rotation....too bad the gms have that small crank bolt, not something I would want to be trying to turn over the engine with, unless all the plugs were out.
Re: Stalling Port engine
Posted: August 19th, 2017, 8:48 am
by km1125
If I got to the crank bolt, then it would be easy. I don't want to do "Pull the belts off, remove the pulley on the dampener, remove the dampener," steps. I figure if I just built a lever with holes where the three bolts for the pump adapter bolts on, it would be easy to turn without all that disassembly.
Re: Stalling Port engine
Posted: December 8th, 2017, 7:05 am
by Viper
Did you get anywhere with this?
Re: Stalling Port engine
Posted: December 8th, 2017, 9:42 am
by km1125
I did not resolve the original issue yet. My engines are setup with switches so either engine can come from either tank. There are also independent lines from each tank to the switches, each with a different anti-siphon valve. So I switched the Port Engine to run on the Starboard tank and the Starboard engine to run on the Port tank. I didn't have any stalling issues while in this configuration. I was going to put them back, port to port and stbd to stbd to see if I could recreate the problem, but never did. I had been planning on redoing several fuel lines over the winter and was going to pull all the anti-siphon valves and inspect and clean them. If I see crud on the one Port one then I'll consider it the culprit and the issue solved for good.
The other work that I did (compression tests, leak down tests, spark plugs and thermostat) was not intended to fix the stalling problem. It was just a convenient time to do those things. The idle speed and mixture might have helped because I did notice this year that my idle speed would vary a bit outing to outing... sometimes being just a bit too fast for "no wake" with both engines in gear and sometimes just a bit too slow for maneuvering during docking. I really don't think this was the
cause of the stalling though, just an irritation. The hard restart after stalling makes me think the carb was dry due to the anti-siphon valve.
Re: Stalling Port engine
Posted: December 8th, 2017, 5:43 pm
by Viper
Winter.....can't do anything
Guess we have to rely on the southern guys and gals to keep us busy with inquiries for the next 5 months
Re: Stalling Port engine
Posted: December 9th, 2017, 6:33 pm
by bud37
km1125 wrote:Source of the post I did not resolve the original issue yet. My engines are setup with switches so either engine can come from either tank. There are also independent lines from each tank to the switches, each with a different anti-siphon valve. So I switched the Port Engine to run on the Starboard tank and the Starboard engine to run on the Port tank. I didn't have any stalling issues while in this configuration. I was going to put them back, port to port and stbd to stbd to see if I could recreate the problem, but never did. I had been planning on redoing several fuel lines over the winter and was going to pull all the anti-siphon valves and inspect and clean them. If I see crud on the one Port one then I'll consider it the culprit and the issue solved for good.
The other work that I did (compression tests, leak down tests, spark plugs and thermostat) was not intended to fix the stalling problem. It was just a convenient time to do those things. The idle speed and mixture might have helped because I did notice this year that my idle speed would vary a bit outing to outing... sometimes being just a bit too fast for "no wake" with both engines in gear and sometimes just a bit too slow for maneuvering during docking. I really don't think this was the
cause of the stalling though, just an irritation. The hard restart after stalling makes me think the carb was dry due to the anti-siphon valve.
Got to thinking about your issue, now I think you may have covered most all,and some extra....good stuff...this is a little out there but...the thing that came to mind was the PCV valve, check yours, sometimes they can stick and leak too much, lead you astray as they seem ok when checked....just spitballin here, I realize the boat is put to bed..........
Re: Stalling Port engine
Posted: November 23rd, 2019, 9:03 pm
by bud37
Km1125, I know this is old, but, did you ever find the culprit for your stalling...????
Re: Stalling Port engine
Posted: November 24th, 2019, 11:24 am
by km1125
bud37 wrote:Source of the post Km1125, I know this is old, but, did you ever find the culprit for your stalling...????
Can't believe it's been two years!!
I am pretty convinced it's the anti-siphon valve, but I haven't replaced it yet. I did not have any problems this year, but I have the engines switched to have port eng run from stbd tank and stbd engine from the port tank. I did a few tests with both engines running from each tank and I'd say it was "inconclusive".
I had planned on replacing (or at least checking and cleaning) all four anti-siphon valves when I redid the fuel lines. Bought all the hose, but still debating on the terminations. The current ones all have crimped ends, which I like. I haven't found replacements for those crimps, so the alternative would be getting hose barbs and clamps, which I don't really like. I did replace the vent, vent hose, and fill hose on the stbd side but didn't get around to doing the port side yet.