Penta 434a v6 with 4bbl holley stalling when shifting into gear, advice please

[win-or-bin]

Hi all,
I have a 434a penta v6 with a 4 barrel holley (4160), last year I noticed that when the engine was up to temp when shifting from neutral into drive slowly sometimes the engine would stall out, if I shifted a bit quicker and gave it a bit more throttle it would be ok as I could then decrese the rev's back?- embarrassing question time - not sure if its an idle problem, I set the idle with the boat in neutral and running on the muffs, but was told by someone that it should be in gear on the water when you set the idle speed, is this right? not sure as this is my first proper inboard! So do I need to rebuild carb, and if so what rebuild kit do I need?, I presume it will have to be a marine holley kit and not automotive one as I think there are some differences in the carbs?
Anyway Thanks as always for the help, learning all the time

 

[Don S]

Re: Penta 434a v6 with 4bbl holley stalling when shifting into gear, advice please

What did you set the idle at? What rpm?
When was the last full tuneup, compression test, filter change, timing check, and carb mixture adjustment?

 

[win-or-bin]

Re: Penta 434a v6 with 4bbl holley stalling when shifting into gear, advice please

Hi,
Thanks for the quick reply. idle set at 750 rpm when running on the muffs, compression test done last april and was all within spec (forgot what each cylinder was at) fuel filter changed april, not done a tuneup/or adjusted the carb mixture since getting the boat last winter.

 

[Don S]

Re: Penta 434a v6 with 4bbl holley stalling when shifting into gear, advice please

If you get everything tuned up and adjusted right, it will probably idle just fine and not die when shifting.

 

[win-or-bin]

Re: Penta 434a v6 with 4bbl holley stalling when shifting into gear, advice please

Thank you Don for the advice, would I be better removing the carb from the motor when doing this?

 

[Don S]

Re: Penta 434a v6 with 4bbl holley stalling when shifting into gear, advice please

You adjust the idle mixture with the engine running at idle. So having it off the engine is of little use.

 

[win-or-bin]

Re: Penta 434a v6 with 4bbl holley stalling when shifting into gear, advice please

just wondered if there was any worth in stripping it and cleaning it will I was at it, can you confirm that idle being set in neutral running on the hose is ok?
Thanks again

 

[Don S]

Re: Penta 434a v6 with 4bbl holley stalling when shifting into gear, advice please

Doesn't do any good to rebuild a carb if there is nothing wrong with it.
Tune it up first, before you go worrying about rebuilding the carb.

 

[RogersJetboat454]

Re: Penta 434a v6 with 4bbl holley stalling when shifting into gear, advice please

can you confirm that idle being set in neutral running on the hose is ok?
Thanks again

IMHO, setting mixture/idle in neutral while the boat is in the water would be the best. That's the condition in which you are going to run the boat. But a hose should suffice until you can get it in the water for fine tuning.

Your neutral idle speed is more critical than idle speed in gear. If you set the idle while in gear, the neutral speed may end up being too high, especially if you're compensating for another neglected adjustment that's out of whack. Too high a idle in neutral, and you'll start beating up the drive when you put it into gear.

 

[beermak]

Re: Penta 434a v6 with 4bbl holley stalling when shifting into gear, advice please

First have the timming checked, then in water and with the engine running for at least 10 mins. start adjusting the idle and mixture screw so u get the spec rpms and get the best mixture. re check timming after and go for a spin.

generally the sped idle is 700/800rpm and the timming 8 degrees

If it works ur done, if not then its time for a good tune and carb rebuild.