1980 140hp v4 crossflow issues

boost3782

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Hello-

This is my first post but I have been checking the site out for some time now and want to say thanks for all the information. I had my 1980 140hp v4 crossflow powerhead and lower unit rebuilt. The power head was gone through and forged pistons were used (130psi per cylinder) it was all balanced and there are boysen glass reeds installed. A new stator, 2 power packs, 4 new coils, OEM fuel pump, and the whole plumbing was redone. I have not replaced the rectifier.

The problem I am having is this baby is super cold blooded and hates to idle. To get her started is an act of congress some times and it requires alot of pushing the key in to choke/add fuel into the cylinders. Also after a run to a fishing spot she will idle fine for a minute or two and then it will stumble around and die. I have noticed that if I add more fuel by pushing the key in it will stay running but has died even adding some fuel in this manner though it has helped more than not. This thing is evil wide open and runs very well top end but this idling issue is killing me.

idles at 900-1100rpms

Any ideas or is there any more info needed please post as I am at my whits end with this outboard. Too much money in it, I just want her to run. Please help :)

Thanks
 

ondarvr

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Re: 1980 140hp v4 crossflow issues

You didn't say anything about work being done on the carbs. Sounds like a fuel delivery issue.

Did you change the low speed jetting that is recommended for these reeds?

It should be able to idle at 650 to 700 RPM in the water, your numbers may be OK on the hose.

Are you holding the key in for a count of 5 to 8 before trying to start it?
 

boost3782

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Re: 1980 140hp v4 crossflow issues

The carbs were completly rebuilt and the jets were added to the carbs for the reeds. I havent ever held the key in, just pumped it in and out. I have noticed that when I run that my pumper bulb is going somewhat soft after I get to a idle point and it dies. I have checked for leaks along with the mech. who built it but he doesnt have the time to go water test this boat as he is a small shop and feels he's lost enough customers messing with my boat all ready due to the massive amount of time hes put into it.

Thanks
 

ondarvr

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Re: 1980 140hp v4 crossflow issues

The first thing is to hold the key in to the count of 5 before trying to start it, pumping it doesn't do much (turn it to the "on" position first).

The squeeze bulb will get a little softer after the engine sarts, that's normal, but try pumping it before, or as it dies to see if that helps.

I assume he put in a new thermostats, but if its stuck open, or he left them out, it can cause issues at idle. (some people leave them out thinking they aren't needed)

Try a different fuel line and tank.
 

boost3782

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Re: 1980 140hp v4 crossflow issues

The first thing is to hold the key in to the count of 5 before trying to start it, pumping it doesn't do much (turn it to the "on" position first).

The squeeze bulb will get a little softer after the engine sarts, that's normal, but try pumping it before, or as it dies to see if that helps.

I assume he put in a new thermostats, but if its stuck open, or he left them out, it can cause issues at idle. (some people leave them out thinking they aren't needed)

Try a different fuel line and tank.


I have pumped the bulb as it was starting to die and most of the time it dies. He did rebuild the whole cooling system. How would I be able to check for a stuck open thermostat? I did put a new fuel line on, but not a different tank.

Thanks for your help so far. I was wondering about the fuel pump. He told me alot of people go to an electrical fuel pump for applications like mine with the new jets in the carbs/glass reeds. Think that might solve my issues? If so what brand would work for my setup or do you recomend.

Thanks
 

ezeke

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Re: 1980 140hp v4 crossflow issues

It is unlikely that the fuel pump has anything to do with your cold engine and idle problem. That's because the pump only fills the float bowls and provides pressure to the primer solenoid. The fuel going through the carburetors is pulled through them by the pistons' vacuum.

The first thing to do is to check the head temperature to make sure that the engine is being warmed properly and if not, to service the thermostats. Get an inexpensive non-contact thermometer gun like a Raytek Minitemp and have at it.

Initially, the only pressure on the fuel supply that is passed to the intake manifold by the primer solenoid is from the primer bulb, so pushing the key in before you crank is limited in effectiveness. When you push the key in while cranking, the fuel pump pressure is added to the supply, making the primer solenoid valve's effectiveness significantly greater. It is most likely the way that your owner's manual tells you to do it.

BTW, it is extremely important to fully raise the remote warm up lever on your crossflow engine. It advances the timing to the correct position for a cold start.
 

boost3782

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Re: 1980 140hp v4 crossflow issues

Is the remote lever your speaking of on the console as in the fast idle lever? Also when checking the engine temp what is the range i am wanting it to be in and how long should it take for it to warm up? Also for checking the spots i'm thinking to shoot are to the sides of the plugs but further back on the head if that makes sense. Sorry im not very clear on the correct terminology. Thank you for the help.
 

ezeke

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Re: 1980 140hp v4 crossflow issues

Check the temperature near the location of the temperature switches (tan wire).

Impossible for me to see your remote, but have someone move move the "fast idle" lever while you watch what is happening at the engine; you need to have the timing advance moving with the lever.

The water temperature coming into the motor determines how long it takes to reach operating temperature, but generally, the motor should reach 125 degrees F. in a few minutes and not exceed 163 degrees under any normal conditions. If the themostat is stuck open you will not reach the 125 degrees. The water is passing through the engine on the way to the thermostats which control the flow as needed. The thermostats should open at 143 degrees F. +/-.

When testing, the usual recommendation is to run the motor in water that is between 60 and 80 degrees at 1100 RPM for 5 minutes, then test.
 

ondarvr

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Re: 1980 140hp v4 crossflow issues

ezeke

I have question about the primer comment you made.

Doesn't the squeeze bulb also supply fuel to the primer? If it does, then pumping the bulb and then pushing the key in would allow fuel to flow into the carb (intake) even without it cranking. I say this because pumping the bulb will supply fuel to the rest of the carb and fill the float bowls without actually having the fuel pump doing anything, plus put the system under a slight bit of pressure.

I do know that all of the motors I use start much easier when the primer has been pushed in prior to cranking. If I don't push it in prior to cranking it will take several more revolutions to start and may not stay running as easily.

Update....Ten minutes later.

After starting this reply I decided to go out and check my 90HP crossflow before I finished typing. When I pumped the bulb it filled the entire system as I knew it would. It also left a small amount of pressure in the sytem, so when I pushed the primer fuel flowed into carb and when I would disconnect or connect the fuel line gas would spray, not just drip out of the connecter.

This leads me to believe pushing the primer prior to cranking will allow enough fuel to flow into the intake to help with starting even though the fuel pump isn't adding any pressure at that time.

Long winded, but details like this are important to me.
 

boost3782

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Re: 1980 140hp v4 crossflow issues

You guys are great! I work 10 hour days so I am having some time issues on getting out there and working on this. I also had a quick question that might be the problem. Ive not replaced the 1979 16 gal tank on the boat. How does the fuel get picked up on these types of marine gas tanks? Is it just a small pipe with a filter on the end? If so could it being partially clogged be the issue. If so would it be wise to replace the fuel tank and start again to see how it does? Thanks again for all your help and I will be working on this as soon as I can.
 

ezeke

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Re: 1980 140hp v4 crossflow issues

I said that pushing the key in before cranking is "limited in effectiveness" and it is (unless you want to stand there repeatedly sqeezing the bulb).

Click the thumbnail for the instructions found in most owner's manuals.
 

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ezeke

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Re: 1980 140hp v4 crossflow issues

The fuel pick up is usually horizontal near the bottom of the tank and has a filter screen. If the filter screen becomes clogged it will restrict the flow of fuel.

At the top of most built-in tanks there is an anti-siphon valve in the fuel outlet. The anti-siphon valve prevents fuel fro being siphoned from the tank in case of a leak in the fuel lines. The anti-siphon valves in early tanks were not designed for ethanol, and they are also subject to blockage from debris and from the gel that sometimes forms in old fuel.
 

ondarvr

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Re: 1980 140hp v4 crossflow issues

I said that pushing the key in before cranking is "limited in effectiveness" and it is (unless you want to stand there repeatedly sqeezing the bulb).

Click the thumbnail for the instructions found in most owner's manuals.

Why do companies print things that go against what I say, they have no right to do that.... LOL.

Thanks, I'll look in my manual to see if it has those instructions.
 

Dhadley

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Re: 1980 140hp v4 crossflow issues

The primer will release fuel that's under pressure in the lines. The pressure either comes from the pump while the motor is running or cranking over or from the bulb being pumped. When you squeeze the bulb you are filling the carb bowls and creating line pressure. Turning the key to "On" and pushing the key in opens the primer and fuel will squirt in the intake. The flywheel does not have to be moving for that to happen. If you hold the key in the fuel will squirt in until there is very little or no line pressure left.

If you'd like to check it just remove a primer line and squeeze the bulb then push the key in while it's in the "On" position. You'll see the fuel squirt until the line pressure drops.
 

ezeke

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Re: 1980 140hp v4 crossflow issues

That's pretty obvious. Did I imply that it was not?
 

emdsapmgr

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Re: 1980 140hp v4 crossflow issues

If the engine idles better with the fuel primer activated, sounds like it is starving for fuel at idle. Possible the idle circuits in the carb bodies may not have been properly cleaned when the carbs were overhauled. Do you know for sure that all the passages in the carbs were properly cleaned with an aerosol carb cleaner?
 

boost3782

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Re: 1980 140hp v4 crossflow issues

I would think so. The guy is real crazy about this engine and calls it his baby. I gave the engine to him in Dec and told him to take his time on it so he did and worked on it over the winter while he was slow. I feel confident he did a good job as he certified with Evinrudes back in 1978 or he made a certificate up and hung it on his wall that says so lol.I got the boat back and took it out to break it in which it would start and idle without a hitch. I noticed after 3 tanks of gas the boat started with these problems of bad idle and hard to start and stay started. I started looking checking the engine out and then noticed something whitish leaking from the lower unit which I opened for a nice ton of water flowing out so the boat sat until I had the cash for him to rebuild the lower unit. I just got this thing back last week and it's still doing this hard starting and idling problems even though he did a CDI check or what ever and found that a power pack had gone bad. They only had 1 power pack in stock so he replaced the bad one and said the other ones on it's way. I pulled the gas tanks pick up a little while ago. It was simply a grey tube with no filter and it was not clogged. I am wondering if replacing the tank or pulling this one (which will suck) and cleaning it out might help if it is bad gas and or tank. I am trying to hunt down a temp gun to check the heads for temp which I should have done in a few days. I really wanted to spend the money and have a pro do this and tune it all out but it's starting to cost me about a half a grand over what he thinks every time this thing goes to him and now he is "too busy" with other clients to take my out and hunt these issues down. Shoot theres so many boats at his shop theres no room to even pull in with a boat. I just want to salvage a little of the summer and be able to use this expensive thing so i figured ill give her a whirl.

Thanks again all and ill keep you posted on what I find
 

ondarvr

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Re: 1980 140hp v4 crossflow issues

Since it had run OK, slowly started to get worse and activating the primer helps, then just clean the carbs. Having clean carbs yesterday means nothing today, worst case you'll have clean carbs and can rule that out.

Now there are two things to do.

1. change your starting method.

2. clean the carbs.

After that, report back and tell us what happens. These are no, or low cost things that can be done right away.

The non contact thermometer can be purchased right now at Harbor Freight for $9.99 on sale.
 

emdsapmgr

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Re: 1980 140hp v4 crossflow issues

Always possible you picked up some debris from the tank and it is lodged in the carb passages. Do you run an inline fuel filter in the hose? I'd also suggest taking a fuel sample to see if you got any water in the tank from a recent fillup-just for peace of mind.
 

boost3782

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Re: 1980 140hp v4 crossflow issues

I have an inline filter but thats after the probelms started as I just put it in a while back. I did replace the fuel line and by passed the filter thinking that was the issue but it didnt help. As for cleaning the carbs is there a step by step on the net some where for me to follow so I can make sure I do it properly?
 
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