1985 140hp VRO Cutting Out (intermitantly)

[toymister]

My 140 started cutting out intermitantly, it is as if 1/2 the motor is working or as if it is running out of gas.

I've been doing a lot of reading here to try to problem solve. I've had it for a couple of years and it sat for a couple before I bought it. Last year it did not get winterized properly, (but this problem started at the end of last season.)

I've changed the fuel filter. When the motor acts up I have tried unplugging each spark plug.. it doesn't make much difference.

I plan on the Seafoam treatment asap using the 3/4 gallon method.

If that doesn't clear it up I'm thinking it may need the carbs cleaned. I beleive i need to remove the starter to get at the carb. is there a write up anywhere on how to do this (I'm going to order a manual but I want to get started asap)

Is there anyway my problem could be the pick up of fuel from the built in tank? or a venting problem with the tank.

This has happended when full out.. I let it sit for a couple of seconds and it starts again, sometimes still running poorly, sometimes completely cleared. I started it one morning (rainy morning lots of moisture) and it seemed worse, I almost wonder if it is an electrical issue but I've looked the motor over and the grounds all look good.. and see no arcing of any wires... but maybe something is happening that I can't see.

Could this be a failing CDI unit?

I'm new to working on boat motors so any advise is appreciated.

Which champion plug and gap should be in this motor

Sorry for the long post.

tom

 

[Walker]

Re: 1985 140hp VRO Cutting Out (intermitantly)

Could be dirty coil grounds.

 

[ezeke]

Re: 1985 140hp VRO Cutting Out (intermitantly)

I think that you should start at the fuel tank and work your way out. A lot of built-in tanks have older anti-siphon valves that are not really satisfactory for today's fuel in the first place and can malfunction with even a very slight amount of debris. The valve is usually located at the top of the pickup tube inside of the fitting where the outgoing fuel hose is connected. It usually consists of a light spring and a ball bearing and is designed to prevent a leaking hose from siphoning all of your fuel into the bilge.

You can knock the bearing and spring out if all of your hoses are higher than the tank, or you can buy and replace the fitting with an updated one.

If the built-in tank vent is blocked - salt spray or corrosion can close it - you would experience similar problems.

 

[toymister]

Re: 1985 140hp VRO Cutting Out (intermitantly)

Could be dirty coil grounds.

Is that readily accessible? Should I try pulling all the grounds off and cleaning them. I haven't seen any corrosion.. but I guess it couldn't hurt.

 

[toymister]

Re: 1985 140hp VRO Cutting Out (intermitantly)

Is that readily accessible? Should I try pulling all the grounds off and cleaning them. I haven't seen any corrosion.. but I guess it couldn't hurt.

The boat has a built in tank. the outlet to the motor has a shut off valve and then a plate on the tank which is held together with 3 scews. I had thought of taking that off to take a look but was afraid to damage anything due to corrosion. I guess the anti syphone could be in this elbow peice and valve?

If the antisyphon was stopping the fuel flow, I guess I wouldn't see any change in volume of fuel in the fuel filter because it would basically create a vacume correct?

 

[ezeke]

Re: 1985 140hp VRO Cutting Out (intermitantly)

Short of taking the fittings apart, the easiest check would be to run on a portable tank with a different fuel line and see if the problem is still there.​

 

[toymister]

Re: 1985 140hp VRO Cutting Out (intermitantly)

Good thought. I will running it on a separate fuel tank and see what happens.

Thank you for all your help.

Tom

 

[toymister]

Re: 1985 140hp VRO Cutting Out (intermitantly)

Update, there appears to be no spark.

Powerpak?

Is there anyway to test a powerpack once removed from the Boat?