1989 GT150 VRO2 conversion to Gas

[sunrize on the water]

It looks like my 1989 J150STLCEM has been converted. Lines are cut and blocked for the oil and fuel in tank is mixed 50:1. However, it has a Holley fuel pump in line and the fuel line is still going thru the VRO?? Is this the way it is supposed to be? Do I need to remove Holley fuel pump and VRO2 and replace with a factory fuel pump? Can I remove Holley fuel pump and go thru VRO2 fuel side? Any assistance would be greatly appreciated. Craig.

 

[boobie]

Re: 1989 GT150 VRO2 conversion to Gas

Remove the Holley fuel pump and try it with just the VRO. The Holley pump is just a fire hazard anyway. If that doesn't work you can get a rebuild kit for the fuel side of the VRO from Maxrules.com.

 

[sunrize on the water]

Re: 1989 GT150 VRO2 conversion to Gas

Thank you for the quick response. I cleaned carbs, kept system as is and motor runs good at no load. It does spit or cough (backfire) periodically back through the carbs. But none the less runs smooth. I took it to the river and applied load and it vibrated uncontrollably and "bogged" down. I will get rebuild kit for VRO2 but now feel there is obviously something else needs attention. the CDI has been replaced by previous owner in Aug 2013. According to wiring diagram, everything seems to be hooked up properly. Unsure if motor has been timed.

 

[emdsapmgr]

Re: 1989 GT150 VRO2 conversion to Gas

A periodic backfire could indicate the engine is out of time. Could be a broken flywheel key, though usually when they shear the engine just won't run at all. If the prior owner replaced the CDI, I'd double check to be sure that all the power pack leads are going to the correct coils. It's easy to get two coil wires switched and that will cause backfires and uncontrollable vibrations.

 

[Silvertip]

Re: 1989 GT150 VRO2 conversion to Gas

Get that electric fuel pump off that engine. Can you say 'KABOOM"? It is not necessary and without even seeing your boat I would bet it is not wired with a safety shut-off. How do I know this? Because there is nothing you can connect to for this purpose without a fair amount of engineering.

 

[sunrize on the water]

Re: 1989 GT150 VRO2 conversion to Gas

Roger that!

Holley pump will be removed and will attempt with fuel side of VRO2.

Ideally, I would like to remove the VRO2 completely from the system and premix.

Will I need to install a diaphragm pump on the motor if the VRO2 system is totally removed?

CDI wires are correct by wire color to each coil to the best of my knowledge.

Service manual/parts catalog ordered from K.Cook today, I can understand most of Seloc instructions, but they expect you to have graduated from MMI or something to grasp the rest.

I found dry rot on one of the fuel lines today, replaced all fuel lines (alcohol resistant).

Did compression check (dry) all cylinders 1/100, 2/90, 3/98, 4/100, 5/98, 6/102 cyl/psi.

I will have to figure out how to link-n-sync and set timing or just have it done.

Thank you all for your guidance.

 

[emdsapmgr]

Re: 1989 GT150 VRO2 conversion to Gas

Your compression is pretty even and common for that year's 150. You can still run premix with just the gas side of the old VRO working, assuming that it's still in good shape-internally.

 

[sunrize on the water]

Re: 1989 GT150 VRO2 conversion to Gas

UPDATE:

First, thank you everyone for your input and guidance....greatly appreciated!

Took Holley fuel pump off, rerouted fuel lines so bulb is outside of the bilge area where it normally goes, cleaned n gaped plugs, cleaned battery terminals, removed oil reservoir and wires from boat. Left the VRO2 two plug connection in motor (unplugged). Plugged up the four wire VRO2 connection.

Started good but ran rough. smoothed out some after warming up. Still rough and smoking like mad.

I will add that the only "oil" line that is blocked is the cowling outside connection. All other oil lines are attached to the VRO2 are still connected and in tact as they were from the factory. Could I be getting air in the system from that if VRO2 side is bad?

I will replace fuel and get timing done. Or wait till service manuals arrive and attempt myself???

Will update as work is done, any other advice on what to look for?

Thanks again.

 

[pn]

Re: 1989 GT150 VRO2 conversion to Gas

do a search on removing vro, you can run two pumps and toss your vro. if you haven't gone through your carbs i'd do that too.

 

[sunrize on the water]

Re: 1989 GT150 VRO2 conversion to Gas

PN,

Removing the VRO2 was my initial idea, I have researched quite a bit so far but haven't found the part number for compatible manual fuel pumps. All the pumps I have found are for smaller engines. Can you (or anyone else) recommend a part number or manufacturer that I can contact to secure these pumps?

My fuel filter (in motor housing) will only fill half full with fuel and half air. I tried several ways to purge the air with no results. I connected the fuel line from the bulb directly to the VRO2 and motor still ran rough.

No problem starting, turn the key and bam, starts right away.

Thanks for the pic, Craig

 

[emdsapmgr]

Re: 1989 GT150 VRO2 conversion to Gas

go out to this website: epc.brp.com. Look up an 83 V6 engine and get the part numbers for the hoses and the two fuel pumps. The pump numbers have been superceded, but are still avail. You will find that each pump will require a pulse line and your current VRO only has one. You will have to remove one of the plugs on the face of the intake manifold and install a second hose barb for the second pulse line. Not a bid deal. The dual pump systems worked for many years, including feeding their big 235's and the 2.6 engines.

 

[sunrize on the water]

Re: 1989 GT150 VRO2 conversion to Gas

emdsapmgr,

Thank you, found the fuel pumps and hoses. Matches pn's pics.

May need a little guidance on the pulse line. Will it require an additional pulse limiter as well (assuming so)?

I haven't found the hose barb. I will look for a plug to remove on the intake manifold and replace with a hose barb.

Would anyone have detailed pictures of this application by chance?

Sincerely, Craig

OBTY: Got my service manual today... wow, what a difference from Seloc!

 

[emdsapmgr]

Re: 1989 GT150 VRO2 conversion to Gas

You should be able to find a second brass replacement hose barb at any marine dealer, or perhaps an automotive parts store. Just make sure it matches the original in thread and hose size. You will install it just like the current one on the engine. Once you have a look at the existing one on your block, you should see what you have to do.

 

[sunrize on the water]

Re: 1989 GT150 VRO2 conversion to Gas

Had to break for a bit and play with the boys on Tank Gunnery range (what fun).

Here is what I have so far:

All parts and components identified to place order (need timing light and tachometer).

Only procedure I have a question about is Max Spark Advance??

Johnson Service Manual, page 1-41, the NOTE states to use the "proper test wheel" and not to use flushing adapter or propeller for this procedure.

I have seen a Dyno in action and understand the purpose of using the proper test wheel. Can I obtain one for a reasonable cost? Is there an alternate way of setting the Max Spark Advance?

 

[emdsapmgr]

Re: 1989 GT150 VRO2 conversion to Gas

Unfortunately for most of us consumers is that the factory manual requires the engine to be running at 5000 rpm's to set max timing. That's due to the timing "creep" that is inherent in the crossflow ignition system. There are a number of ways to set it at 5000, including a test wheel, or setting it on the trailer at the boat ramp (just the prop and water intakes in the lake.) I have seen some test wheels advertised on ebay, but you need to get the correct one. They are not made anymore and the V6 ones are rare. If these two methods are not convenient, go up to the top thread on this web page and look up the "Joe Reeves" special timing procedure. His works and will get your timing close enough.

 

[sunrize on the water]

Re: 1989 GT150 VRO2 conversion to Gas

Apparently my antiquated "rookie" skills need to be tuned? Dyno vs Test wheel... Bet y'all got a good chuckle on that one. Good article by J.Reeves and other home remedies by fellow contributors. Waiting on parts. Hopefully get to this over the weekend. Thanks everyone.

 

[sunrize on the water]

Re: 1989 GT150 VRO2 conversion to Gas

Update. VRO2 conversion completed. Very easy. I will post pictures later (raining now). Lucky in that per existing holes in manifold to mount upper and lower fuel pumps. Completely rebuilt carbs. Replaced all fuel line inside cowling with OMC "ethanol friendly" line. Replaced outside the cowling to tank with Yamaha fuel pipe assy (hose/bulb) kit.

Test ran and it spits out of top and middle carbs. Some mist and what looks like smoke?

Have not done idle, timing or replave fuel yet because of rain.

 

[emdsapmgr]

Re: 1989 GT150 VRO2 conversion to Gas

Possible you've got a carb problem. The float may be sticking. Could be timing: If the engine is out of time it will backfire and can cause fuel spitback out of the carb throats. You can look for some other potential problems: the flywheel key is sheared and the flywheel is out of position, one or two coils are connected incorrectly (backward) to the power pack, or you've got a reedbox problem-maybe a cracked reed. Usually when a coil wire is switched, you've got a pretty violent carb backfire-which is really noticeable.