86 Johnson 175 VRO

[Wayne65]

I was replacing fuel lines and when I pulled the pulse line from the block it was oozing black filthy oil. Would this be coming from the oil side of the VRO or could it be coming from somewhere else? I have the powerhead sitting on a bench right now for other issues and and can easily look further if there could be another potential problem. I plan on replacing the VRO with an earlier model non oiling pump and premix anyway because I want to be able to run my 2 stroke kicker off the main tank. Also there doesn’t appear to be a pulse limiter on this engine. Should I install one?

 

[flyingscott]

The VRO may be bad. But if you are going to replace it with the earlier double pump don't worry about it. You do not want a pulse limiter with a non vro pump.

 

[Wayne65]

The more I tear into this thing the more problems I find and was just wondering if I should look any further while it’s apart.
thanks for the info.

 

[racerone]

The pulse line operates with air and clean fuel / oil / air mix.----So if there is black filthy oil in there you have problems.-----Did you do a compression test on this motor ?-----Might as well pull the cylinder heads and examine cylinder walls.---Remove bypass covers and look at pistons / rings from the side.

 

[Wayne65]

I did check compression just before pulling the powerhead to replace an upper grommet on the water tube that was leaking badly and I got 112 to 115 in every cylinder.
I guess I could pull the VRO pump apart to see if I can find an issue there. I also will take your advice and pull the heads and bypass covers to inspect just for piece of mind. Thanks for the advice. I was also getting a light buzzing sound from the mid section that i have yet to determine the cause. I did find a blown gasket by the water tube on the inner exhaust housing but I’m not sure if that would have made any noise.

 

[cfauvel]

the yucky oil crud is most probably coming from the reset pin's o-ring.

refer my thread to see what I'm talking about...
https://forums.iboats.com/forum/eng...tle-insight-into-the-oil-side-of-the-vro2-oms

the o-ring in question is available.

Your year VRO is the first year of the electronics(if it is a 3 wire version)....the four wire version is better.
This will fit your motor...if you want to go new:

https://www.ebay.com/itm/New-Johnson-Evinrude-Outboard-VRO-Fuel-Oil-Pump-5007423-OMC-BRP-Made-In-USA/260967533491?epid=1230515892&hash=item3cc2e08bb3:g:fH8AAOSwGVFcAbA7

Both are the 4 wire models:

5007423 will supply the fourth wire needed

5007420 will not and assumes you have the extra fourth wire already

DO NOT buy a new vro that is in the 160-200$ range ...it will be a knock off and have a 50/50 chance of working right out of the box.

 

[Wayne65]

Thanks for the info. I plan on pre mixing the fuel so I can run my kicker off the main tank and will be removing the VRO. Would the bad seals on the reset pins cause the oil/ crud to go into the pulse line to the block? My concern is it is coming from the block and not the VRO. I haven't had time to dig into it further but just received all the gaskets and plan on working on it over the weekend.
I have another question. Is there a way to test the overheat alarm. The motor had to be running hot and I never got an alarm. The upper grommet on the water uplift tube was in bad shape and leaking when I put the water hose to it. This was the reason I pulled the power head. The water tube itself was bent in places it shouldn’t have and pretty beat up. I purchased a new tube and it’s 3/4” longer than the one that was in it because of all the bends. It couldn’t have been seating all the way down in the water pump and it was going in at an angle. I wouldn’t think it was cooling properly and should have gotten an alarm. I also had the regulator, Stator and a power pack go bad. I’m guessing from overheating.

 

[cfauvel]

Thanks for the info. I plan on pre mixing the fuel so I can run my kicker off the main tank and will be removing the VRO. Would the bad seals on the reset pins cause the oil/ crud to go into the pulse line to the block?

No, that would be a rip in the air pump's diaphragm ...at the very least it would need a diaphragm repair kit...but being so old.....

My concern is it is coming from the block and not the VRO. I haven't had time to dig into it further but just received all the gaskets and plan on working on it over the weekend.

If the oil crud is not in the pulse line, but at the bottom...I would suspect some other gasket leak....which is beyond my knowledge

I have another question. Is there a way to test the overheat alarm.

The simplest thing to do is follow each temp sensor wire, under a sheathing there will be a blade connector that disconnects like a switchblade. Disconnect each one....and with the KEY to ON....ground each one to see if the horn sounds.

If not....chase down why....bad wiring or bad horn.....horn should chirp when key is turned to ON

if so, then remove the temp sensors, get a multimeter, attach the leads of multimeter to the blade connector and the front face of temp sensor....dunk temp sensor into a pot of water along with a thermometer, and bring water to boil.
With multimeter set to CONDUCTIVITY you should have 0 connectivity initially then the contacts close before the water boils.

The motor had to be running hot and I never got an alarm. The upper grommet on the water uplift tube was in bad shape and leaking when I put the water hose to it. This was the reason I pulled the power head. The water tube itself was bent in places it shouldn’t have and pretty beat up. I purchased a new tube and it’s 3/4” longer than the one that was in it because of all the bends. It couldn’t have been seating all the way down in the water pump and it was going in at an angle. I wouldn’t think it was cooling properly and should have gotten an alarm. I also had the regulator, Stator and a power pack go bad. I’m guessing from overheating.

oh wow you are going DEEP

 

[cfauvel]

I was replacing fuel lines and when I pulled the pulse line from the block it was oozing black filthy oil. Would this be coming from the oil side of the VRO or could it be coming from somewhere else? I have the powerhead sitting on a bench right now for other issues and and can easily look further if there could be another potential problem. I plan on replacing the VRO with an earlier model non oiling pump and premix anyway because I want to be able to run my 2 stroke kicker off the main tank. Also there doesn’t appear to be a pulse limiter on this engine. Should I install one?

Sorry my reading comprehension is apparently poor.

I thought the black oil was oozing from the oil inlet, not from the pulse line...disregard pretty much everything that came from me....

 

[Wayne65]

Thanks so much for the info. I don't get any audible sound when turning on the key and will do the tests you suggested today. If the issue is at the helm it’s going to be a challenge due to being very difficult getting to any of the dash wiring. 1988 Grady White overnighter.

 

[Wayne65]

Update. I pulled the heads and found scoring on the number six cylinder. The scoring isn’t deep and is even all the way around. Is there any potential issues with boring one cylinder 10-20 over and just honing and putting new rings on the other cylinders?

 

[cfauvel]

Update. I pulled the heads and found scoring on the number six cylinder. The scoring isn’t deep and is even all the way around. Is there any potential issues with boring one cylinder 10-20 over and just honing and putting new rings on the other cylinders?

interested in hearing racerone reply to those questions.

reading the proper procedure to split the case and remove the connecting rod, doing the work and properly re-install the connecting rod would scare me.

There is apparently a special tool to use to properly mate the connecting rod's cap to the rod so that they are perfectly aligned (I assume it is because of the roller bearings)

I'd be worried to try to just hone with the piston in place.. let's see what racerone says...he seems to have rebuilt motors

our motors are so old it is hard to find the special tools...a machine shop specializing in engine rebuilds will have the tools (hopefully)

 

[Wayne65]

I didn’t have a problem splitting the case but I went to pull one connecting rod and didn’t realize the roller bearings were loose in there and would definitely be tough to put back together trying to keep them in place. Are they supposed to just fall out of the retainer that holds them in place? I planned on removing the pistons and crank and taking the bare block to a machine shop but I’m re-thinking that decision right now.

 

[Wayne65]

I got it completely disassembled down to the bare block and took it to a a friends machine shop to take a look. There are actually two cylinders with some scoring and every piston has the bottom ring stuck in the grove from carbon build up. I’m surprised this motor even ran. I’m thinking about buying a complete rebuild kit .20 over. Can anyone recommend a good place to order from.

 

[cfauvel]

I got it completely disassembled down to the bare block and took it to a a friends machine shop to take a look. There are actually two cylinders with some scoring and every piston has the bottom ring stuck in the grove from carbon build up. I’m surprised this motor even ran. I’m thinking about buying a complete rebuild kit .20 over. Can anyone recommend a good place to order from.

did you mark each connecting rod to it's cap and piston?

yeah a .10-.20 over sounds like a good plan..

I would think the roller bearings would be in a cage that keeps them in place..

 

[Wayne65]

Yes I scribed a line on both sides of each rod cap before removing them from the crank. They went right back on the rod as it was removed. I should be able to line those marks up when I reinstall them. The needle bearings on both ends of the rods aren’t in a cage they are loose and fall out as soon as you remove the end cap. After removing the first rod cap I used a strong magnet to catch the needle bearings and it worked great. I will be waiting on parts now. I need a new piston for the machine shop to match it to the cylinders.

 

[Wayne65]

Thanks for everyone’s help. I’m glad I racerone’s advice and removed the heads. They don’t call them a boat for no reason. Break out another thousand. Walleye fishing will have to wait a few more weeks.

 

[racerone]

No need for the special tool to assemble the rods / caps.-----You could throw the caps in one box and the rods in another box.-----Then it is no problem to select the cap and find the rod that it matches.----It really is that simple !!

 

[Wayne65]

I see what you mean racerone. It is very obvious if you try to put the wrong cap on a rod or have it reversed.