testing VRO fuel pump?

[Mankato-Ice-Man]

I have a 1987 Evinrude 40 HP E40TLCUD that starts and idles great. From about 1/3 throttle or higher, it bogs down and seems starved for fuel. Carbs were just cleaned, fuel is brand new with seafoam added. I checked the fuel filter and it was clean.

All of my research shows its probably the fuel pump.

My question is, before I spend 400.00 on a new pump, is there a way to test the current one? it looks like a job and a half getting it out, but if thats what needs to happen thats fine. It doesnt appear there is a rebuild kit available for this pump, so if it turns out bad, I will have to decide going new used (for 150.00).

[gregg52]

i had 89 60

i believe when mine acted like that it was the piston or the ringsis was a good motor for along time but finally gave up

i'm not saying that's your problem..i'm no mehcanic by no means

actually if u still the vro pump omn there thats pretty good

i had mine rebuilt once and he didnt put it back on

[Mankato-Ice-Man]

Did a compression check and both cylenders seemed fine, so I think its a fuel issue.

[Surface Tension]

Check the impulse line from the crank to the pump for a loose connection or a cracked line..

You can rebuild the gas side of the pump but not the oil side.

[boatfixer]

Fuel pressure should be at least 3 psi at an idle and could go as high as 12-15 at wot.

You can get a diaphram kit for the fuel side. The last part number I have is 436095. That is the BRP (OMC) number and you can also get a diaphram kit for the air motor part # 435921.

[Mankato-Ice-Man]

Thanks guys. I would sure like to try rebuilding the gas side for 30.00 before I put in a used pump for 150.00 or a new one for 400.00. Appreciate your input very much.

I did check all the lines tonight, all seem like they are new and are all tight.

[Surface Tension]

Have you checked drop tube and check valve(corroded) inside the tank along with all the connections.

[Mankato-Ice-Man]

Bought a new tank today. Wierd results. I will try to explain this as well as my pea-brain can get it in to text...

NEW TANK- pumped up bulb, motor started, backed off trailer, seemed like the issue might be solved, back away from dock, shift in to forward, motor kills. Fuel bulber flat. Cant pump it at all. Unhook the hose at the motor end of the hose, no change, unhook at tank end of the hose, pressure on bulber releases, can pump fuel again, but bulb never feels more then 1/2 full, cant get enough pressure on the bulber to pump fuel to keep motor running. Trolling motor back to dock, call wifey to bring out old tank because I was stupid enough to not leave it in the boat. Hook up old tank, bulber pumps up tight, stays tight. head back away from dock as motor start up again, idled fine. BUT, motor acted the way it has the whole time which is---

OLD TANK- bulber tight, pumping bulber while running motor makes no change to how crappy it runs. Idles fine and runs out to about 1/3rd throttle or so, then its bogged down, like the choke is on or like I am pulling 2 five hundred pound skiers behind me. Like I said, pumping bulber does nothing, BUT, if I push the key in, which I assume is some sort of primer or choke???, the motor revs right up, roughly, but the boat speeds up considerably.

So I am now totally confused. Why the two separate issues with the tanks? Do I have a fuel pump issue or something hosed in the carbs, that I was told were just gone through this spring?

Thanks in advance, I am going to go start drinking now….

[boatfixer]

I dont believe you have a fuel pump issue. Thats what sucked your bulb flat on the new tank.

The new tank? well thats another issue. something is prohibiting fuel flow at the tank. connector or pick up tube.

It sounds as thought there is a problem with carburation. Stuck needle, plugged high speed, out of synchronization. It may even be the fuel filter even tho it looked clean.

Have you checked to see if the butterflies open all the way?

[Surface Tension]

I agree with Bruce in that your fuel pump is working because it collapsed the hose.

I have to say this first, is your hose on backwards.

A 40 hp on a remote tank. What dia is that fuel line? Could be your hose is too small and restricting the amount of fuel to the carb.

Another hose question. What condition is the hose in? As in cracks and connections but a big one is the interior of the hose.

I've seen aftermarket hoses where the interior lining falls apart or swells, yes even when they are fairly new. They are supposed to be alcohol resistant but they if they come from China I can see the problem.

I make my own fuel lines by visiting the autoparts store and buying UV resistant fuel line. I'll get the new bulb and fitting from any big box store but NOT the fuel line.

Your old tank you might want to take it apart and check the drop tube. If could be rotted off or plugged.

Once your positive the fuel line and tank aren't the source then its time to remove and clean the carbs.

[wastewaterguru]

If compression is good as mentioned, I would look at electronic failures as possible causes as well. To eliminate the fuel pump failure as a possible cause, mix gas at 50:1 in a seperate tank and connect directly to the carb. Elevate the tank above the carb and make sure tank is vented (partially open cap). Motor should run up to WOT without starvation. If it runs fine then you know the pump or fuel delivery is the issue.

If it doesn't work.....look at other potential issues. Those motors have been known to have the magnets under the flywheel come loose as well. This throws off the timing. Other linkage issues can cause the timing to creep as well. Make sure the timing base under the flywheel is in the correct location and check the timing with a timing light. I don't remember the specs but I think it's like 0 at idle to 19 degrees advanced at WOT.

I would also check the ignition as these have high and low speed stator windings as well. if the low speed runs smooth and the high speed rough, you may have a failed or failing high speed coil bank on the stator.

[Mankato-Ice-Man]

Update--

But first, I want to really, really thank everyone for your replies... even the one about having the hose on backwards, ha ha. Thanks for taking the time to help an [PoorWordUsage] like me out.

Ok, so today, I'd had about enough and decided to call the guy I bought the boat from. He couldnt have been nicer. He called the place that had worked on the boat this spring to explain that he had sold the boat to me and what was going on and that I would be calling. I called and could not be more happy with what I found out and most importantly how i was treated. The guy I talked to said he is 99% sure its plugged high speed jets. When the guy I bought the boat from brought it it, he told them to get it ready for resale, not get it water ready as he told me were his instructions. The difference to the shop was, resale = make boat start, make boat idle nice. done, water ready = that + put boat on dyno or on water and make sure its tuned under a load. Here is what makes me happy. they said they have a fuel additive make by Evinrude that he says there is a 50/50 chance will clean them out, and if not, they will clean the carbs at a discount for all of the confusion, he figured $50-$75 tops, unless there were broken parts. Now I wish I would have done this two weeks ago and not messed around with it myself, but at the same time, I know a lot more now and I have a new tank and all that. BTW, new tank works after I put a new end on the hose, so thats very good too.

Might be a light at the end of the tunnel yet. Thanks again for everyone's help and advice. I will try and post one more snip-it when the boat is running at full speed for sure.

[boatfixer]

Im glad to hear they are willing to work with you! Let us know how things work out!