Unburned fuel at idle, not charging, no tach, 1990 90 hp Johnson

[lmuss53]

Re: Unburned fuel at idle, not charging, no tach, 1990 90 hp Johnson

Thanks again for the information. I don't have any issue with the VRO, it was unhooked when I got the motor. I saw a universal pump from Sierra for OMC 7to 150 HP that looks like it could be fitted to the pulse line either by putting a nipple on it or making a flat manifold with a nipple to mount it on. I am a machinist so I could make whatever I need to mount it myself.

I was also looking at the 2 to 4 lb Mr. Gasket electric inline pump but lots of what I read about them says to leave that alone.

The kids missed their ride, the local BRP place is apparently doing so well during the week that he can afford to close all day Sunday. I'll get something together this week.

What did the 88's and commercial V4's use that had no VRO? Would that pump be a cheaper alternative? My manual is down in the truck I think I'll look at what they used on those non VRO motors.

 

[Craig-]

Re: Unburned fuel at idle, not charging, no tach, 1990 90 hp Johnson

Thanks again for the information. I don't have any issue with the VRO, it was unhooked when I got the motor. I saw a universal pump from Sierra for OMC 7to 150 HP that looks like it could be fitted to the pulse line either by putting a nipple on it or making a flat manifold with a nipple to mount it on. I am a machinist so I could make whatever I need to mount it myself.

I was also looking at the 2 to 4 lb Mr. Gasket electric inline pump but lots of what I read about them says to leave that alone.

The kids missed their ride, the local BRP place is apparently doing so well during the week that he can afford to close all day Sunday. I'll get something together this week.

What did the 88's and commercial V4's use that had no VRO? Would that pump be a cheaper alternative? My manual is down in the truck I think I'll look at what they used on those non VRO motors.

I believe there may be a boss on the port side for retrofit, might even be drilled and tapped. The one from your parts motor should do it, electric presents other complications.

 

[lmuss53]

Re: Unburned fuel at idle, not charging, no tach, 1990 90 hp Johnson

I took the VRO pump off this evening and took it apart. Everything seems to be in real good condition. All the diaphrams are soft and flexible with no holes anywhere, everything is clean and tight. I covered holes and blew through other holes and all the valves and diaphrams seem to be sealed up when they should be.

Is it typical of these pumps to fail and not look like anything is wrong?

I looked the line over and it seems to be in good condition. I will see if I can round up a vacuum gauge and test it per the procedure in the manual.

I could not get the squeeze clamps anywhere around here so I have zip ties on the lines, I will stop at the BRP dealer and get 10 of the squeeze clamps tomorrow too. I used good zip ties, properly deployed, so I don't think any of them is leaking but I'll change them anyway.

I'll stop and get the same pump off the donor motor tomorrow and see what it does, after I check the vacuum and change out all the clamps.

 

[Craig-]

Re: Unburned fuel at idle, not charging, no tach, 1990 90 hp Johnson

I took the VRO pump off this evening and took it apart. Everything seems to be in real good condition. All the diaphrams are soft and flexible with no holes anywhere, everything is clean and tight. I covered holes and blew through other holes and all the valves and diaphrams seem to be sealed up when they should be.

Is it typical of these pumps to fail and not look like anything is wrong?

I looked the line over and it seems to be in good condition. I will see if I can round up a vacuum gauge and test it per the procedure in the manual.

I could not get the squeeze clamps anywhere around here so I have zip ties on the lines, I will stop at the BRP dealer and get 10 of the squeeze clamps tomorrow too. I used good zip ties, properly deployed, so I don't think any of them is leaking but I'll change them anyway.

I'll stop and get the same pump off the donor motor tomorrow and see what it does, after I check the vacuum and change out all the clamps.

Try hooking the oil back up if you have the tank and all.

 

[lmuss53]

Re: Unburned fuel at idle, not charging, no tach, 1990 90 hp Johnson

I ended up putting a pump for an 88SPL on in place of the VRO pump. I used the Sierra 18-7352 pump and the motor runs like a charm. The 1985 motor has the boss in the side to mount the non VRO pump to. I had to remove the fitting and plug the VRO pulse hose outlet with a 1/8 NPT brass pipe plug. The motor ran great tonight at all speeds on a 1 hour 15 mile midnight moonlight cruise.

I haven't had a chance to see if the carb rebuld and the new pump did anything for the unburned fuel problem I started the thread about.

 

[patrick4266]

Re: Unburned fuel at idle, not charging, no tach, 1990 90 hp Johnson

I have been following this thread. Glad you got her fixed and thanks for letting us know the solution. I hate it when ask for help, get it fixed and never tell you what the problem was.