Vapor Lock Remedies?

[Rockster]

Does anyone know how to prevent and stop vapor locking?

I/O 5.0 mercruiser 2 barrel

Thanks

 

[Bondo]

Re: Vapor Lock Remedies?

Ayuh,... Welcome Aboard,...

What are your symptoms,..??
Whom/ How was vapor lock diagnosed,..??

 

[Rockster]

Re: Vapor Lock Remedies?

Ayuh,... Welcome Aboard,...

What are your symptoms,..??
Whom/ How was vapor lock diagnosed,..??

I am not sure if this is my problem but after reading about vapor lock it sort of fits my problem that I am having.

My engine will start right up on the first crank then I let it warm up to 120 degrees.

I then can cruise all day with no problems but as soon as I slow down to put it in neutral it stalls then I have to let it sit for hours before it will start again.

This is the first year I have had this problem. I had the carb rebuilt the first time this happened and right after that it did it again.

 

[jtmarten]

Re: Vapor Lock Remedies?

Doesn't sound like vapor lock if you're trying to restart it immediately, ie no heat soak time. Sounds almost like the shift interrupt is sticking, or the lower shift cable is really bad causing it to stick.

 

[gleavens]

Re: Vapor Lock Remedies?

I'm having almost the same problem with my rig and I think it's vapor lock as well. It has all the symptoms ( runs great when cool, after heating it up for an hour or so it stumbles @ idle, then stalls, won't resart until it cools down) of vapor lock as I know it. Carb has been rebuilt, new fuel/water seperator installed. I'll be watching this post for updates, or new ideas.
As far as remedies if indeed it is vapor lock, Moroso, and Mr. gasket make a product called "cool cans" which run the fuel through a cannister filled with ice or dry ice to cool the fuel, I'm not sure about the marine environment though for this type of setup. The other question is, for myself as well, is why? Why would it get hot enough to vaporize the fuel?

 

[EddiePetty]

Re: Vapor Lock Remedies?

.....doesn't sound like vapor lock to me either!!

Sounds more like a flooding condition.

Try this the next time it happens to ya'.

Remove the flame arrestor, ensure that the choke is fully open and ever so slowly open the throttle all the way WITHOUT pumping gas through the accelerator pump. Blow down the carb's throat to clear vapors and inspect for LIQUID fuel either dripping from the venturi nozzles or puddled in the intake beneath the carb.

IF the engine decides to idle, you may also inspect the venturi nozzles for drips with the engine running.

Either way, it's carb rebuild time

 

[mdlee]

Re: Vapor Lock Remedies?

Check your plugs, points, timing. Sounds 2 me like you getting poor fire,, witch can seem like a fuel related problem.

 

[aktrucker]

Re: Vapor Lock Remedies?

I am no expert, but sounds a lot like flooding to me.......in fact, I had the exact same problem after buying a rebuilt carb and it was flooding horribly.

Did the float get replaced with the rebuild? Could be if the old float was used that the float is fuel logged and not floating. As stated above, check for signs of flooding, then go from there.

 

[Rockster]

Re: Vapor Lock Remedies?

I am no expert, but sounds a lot like flooding to me.......in fact, I had the exact same problem after buying a rebuilt carb and it was flooding horribly.

Did the float get replaced with the rebuild? Could be if the old float was used that the float is fuel logged and not floating. As stated above, check for signs of flooding, then go from there.

Not sure if the float was replaced but did notice that all of the screws that hold the carb together had backed out. not good!
I have not been out since but tighten up the screws and replaced the fuel filter runs great under muffs but I am sure it will be a different story once on the bay.


Thanks for the responses

 

[gleavens]

Re: Vapor Lock Remedies?

.....doesn't sound like vapor lock to me either!!


Remove the flame arrestor, ensure that the choke is fully open and ever so slowly open the throttle all the way WITHOUT pumping gas through the accelerator pump. Blow down the carb's throat to clear vapors and inspect for LIQUID fuel either dripping from the venturi nozzles or puddled in the intake beneath the carb.

Turns out you're on the money with my issues! I did exactly what you recommended when my engine stalled and sure enough, fuel dripping steadily out of venturi nozzles , FLOODING ! Out comes the carb for a new float and adjustment, will test this weekend, Thanks EddiePetty

 

[EddiePetty]

Re: Vapor Lock Remedies?

.....


Turns out you're on the money with my issues! I did exactly what you recommended ......... FLOODING ! Thanks EddiePetty

No problems, the exact same thing happened to me several years ago.

Glad my experience has helped another!!!