Engine bogs after take off 1988 evinrude 150xp

[azbassinjay]

I have a 1988 evinrude 150xp, since I have bought my ranger bass boat with this engine it has started to bog down. Initially it would only bog every once in a while and over time it has become much worse. I changed the spark plugs, new inline fuel filter, and cleaned and rebuilt all three carbs with carb kits. Also I pulled out as much as gas and possible and replaced it with new gas. I didn't adjust the carbs, not knowing really how to do that. I took my boat out and it ran almost normal in the morning, it seemed like it may have been missing a little of the top end. Later in the day I was moving spots and it was hard starting and then it starting going at a decent speed and then started to bog and would verily go. It would drive very slow and at times act like it wanted to speed up and then it would drop back down in speed and sometimes cut out and die. I am wondering if it is the vro fuel pump. My father and I also thought that it maybe overheating. I have been doing some research on hear and I have so many ideas of what it can be. My intuition has me believing that it has to do something with the fuel pump. Any help would be greatly appreciated.

 

[Mas]

Re: Engine bogs after take off 1988 evinrude 150xp

Can you leave your hand on the motor for a three count at idle? Overheating can bog a motor.

Try pumping the fuel bulb while it's acting up...if rpms increase...look to your fuel pump.

If the temp is fine, fuel pump is fine, you still may have a carb issue.

MAS

 

[azbassinjay]

Re: Engine bogs after take off 1988 evinrude 150xp

I haven't tried holding my hand on the engine yet. I have tried the trick of squeezing the primer bulb when driving it to see if it gets a surge or helps it run with no change. Also the bulb pressure seems good. The carb kits I used I replaced the gaskets, inlet needle, floats, and o-rings.

 

[tashasdaddy]

Re: Engine bogs after take off 1988 evinrude 150xp

did you remove the jets and clean them. if not you wasted your time. read this: http://forums.iboats.com/showthread.php?t=244013

 

[azbassinjay]

Re: Engine bogs after take off 1988 evinrude 150xp

I pulled apart the carbs and sprayed carb cleaner through all the jets, and compressed air through them aswell. I didn't soak them over night. I didn't try the wire trick, but I looked at each jet to see if I could see light through them and none of them really looked clogged.

 

[azbassinjay]

Re: Engine bogs after take off 1988 evinrude 150xp

I have been thinking about removing the vro pump and putting a normal fuel pump and pre-mixing the oil myself. I just dont want to remove the vro if its not the real problem.

 

[BJBUSYBOY]

Re: Engine bogs after take off 1988 evinrude 150xp

I had a very similar problem with my 1984 150hp, it ended up being a gummed up timer base. If you take the cowl off at the lake and throttle up, look back at your timer base and make sure it's advancing at the same speed as you move the throttle handle. If there is any delay or if it stops as you push foward on your throttle you'll find your bogging problem!! You should have fixed jets, if so, no adjustments are required. Let us know what you find!!

 

[azbassinjay]

Re: Engine bogs after take off 1988 evinrude 150xp

I am not sure what the timer base looks like, I will have to look it up. Do you think that it would cause it run fine sometimes and other times bog? I was driving it and it drive fine and then all of a sudden just bog way down and sometimes shut off. I am wondering if it just starving for fuel because the fuel pump may not be functionally properlly.

 

[ezeke]

Re: Engine bogs after take off 1988 evinrude 150xp

You can move the throttle and observe the advance with the engine off. It will be easier to engage if you take the plugs out and turn the flywheel a little.

A lot of bogging is caused by air leaks in the fuel system, so look there first. Especially, look for fuel leaks of any kind; if fuel can leak out air can and will leak in.

Here's a link to a video by MD that shows a similar problem: http://www.youtube.com/watch?v=SEbW-6eOc5I

 

[azbassinjay]

Re: Engine bogs after take off 1988 evinrude 150xp

My father talked to a boat mechanic at a local marine, and he said that it sounded like it is the water pump. He said to check the compression to see if everything is alright with that. The engine does seem to run better in the morning then later in the day. I wonder if it is over heating and that is causing it to bog and loose compression and that is why the engine will cut out sometimes running.

 

[azbassinjay]

Re: Engine bogs after take off 1988 evinrude 150xp

I did a compression check on each cylinder
1. 80 psi
2. 85 psi
3. 80 psi
4. 80 psi
5. 90 psi
6. 85 psi
From my readings I believe that the compression is good, since I didn't see that there was a specific number in the manual I was shooting for. It did say that things should be fine as long as they are within about 5 psi of each other. One is 10 psi more than the lowest, should that sound a alarm for me?
Also I was looking around my motor with a flash light and looked at the back of the VRO2 pump and saw that there is a crack in the back of it. There was some oil on the surface of it, also some surrounding. I am beginning to believe that I found the problem. I am assuming since there is a crack I am loosing oil pressure and that is why it is bogging and cutting out at times. I did buy a water pump believing that it may have been the culprit, but now I do believe it is the VRO2 pump. I am going to go ahead and put in the water pump, it can't hurt and would probably help to rule that out as well. Let me know what you guys think.

 

[azbassinjay]

Re: Engine bogs after take off 1988 evinrude 150xp

I am going to change out the fuel pump and now the question is should I continue with another VRO 2 pump or should I change it out with another and pre-mix. Let me know what your opinions are.

 

[ezeke]

Re: Engine bogs after take off 1988 evinrude 150xp

The VRO2 pumps were last installed on new motors in 1992, so they are way out of date.

The newer OMS pumps for your motor are and have been available since 1993 complete with updated 4 wire harness parts.

You should be OK with a licensed BRP dealer if you ask for the most up-to-date conversion kit available.

 

[Benny1963]

Re: Engine bogs after take off 1988 evinrude 150xp

your comp numbers for the xp are on the low side check the part numbers on your heads and repost ,could probaly use a decarb,if ya have the xp heads the numbers are a little low ,but if your runnin the bathtub head with thick head gasket thats not so bad the numbers are equal you need to check
all fuel lines for air leaks try pushing in your primer - choke at key to see if it picks up speed ,if you are runnin the old vro sys either upgrade$$$
or go to manual pumps and mix 50 ta 1 also check timer base as said in rerlier post also link and sink will cause to bog if carbs are opening before timer base starts to move look in your carbs at throttle plates advance throttle see
if your throttle plates start opening before timer base starts to move
check your spark plugs .if you are runnin surface gap go to Ql77jc4 gapped at 030 or 035 if ya have manual use it if ya dont get one oem,
if ya keep haveing probs repost i have built three of these and have had similiar tuneing probs good luck Bennyb

 

[azbassinjay]

Re: Engine bogs after take off 1988 evinrude 150xp

I am going to work over the next week and let you all know how things turn out. I am leaning towards the manual fuel pump and pre-mixing because of price.

 

[azbassinjay]

Re: Engine bogs after take off 1988 evinrude 150xp

Does anyone know what part # or model # of after market fuel pump I can put on to take out the vro2 pump. I have an evinrude 1988 150xp.

I was thinking of going with sierra because they seem to be the cheapest. Replacing with the vro pump is $300 plus and I can't afford that right now.

 

[ezeke]

Re: Engine bogs after take off 1988 evinrude 150xp

The 150 lift pump system required two lift pumps. The system was stock in 1983 so you could get the parts list for that model from the BRP site.

If you are concerned with the VRO pump, why not just convert it to pre-mix and use it that way - it won't cost anything and it's pretty foolproof as long as you remember to add oil whenever you buy gasoline.

 

[azbassinjay]

Re: Engine bogs after take off 1988 evinrude 150xp

The vro pump has a crack in the back and it is leaking some oil through the crack. I thought about just patching the back with some JB weld, but I think that could be a problem if the vro failed and something caused the crack internally. How would I just convert it to pre-mix without spending any money? I thought by converting it to pre mix meant that I had to replace the vro with another fuel pump.

 

[BJBUSYBOY]

Re: Engine bogs after take off 1988 evinrude 150xp

TO BYPASS THE VRO-You can cut the oil hose 2-3 inches from the pump then plug it with anything that will fit and use a hose clamp to secure the plug. Also, disconnect the wires from the VRO to the wire harness as you'll get an alarm if you don't. Then premix 50:1! You DO NOT need another pump as you just bypassed the oil and the fuel pump will operate normally. If you've decided to just patch the leak, make sure you clean any oil and gas that may be on the surface to be repaired and scratch,sand or scuff the area with fine grit sandpaper or what ever it takes to ensure that the JB weld will stick. I did the same thing to my pump, JUST MAKE SURE YOU ALLOW 24 HOURS for the JB weld to set, or your leak will come back!!! Hope this helps.

 

[azbassinjay]

Re: Engine bogs after take off 1988 evinrude 150xp

Thanks for the help, I guess now I need to decide whether to go without the pump or just patch it. I am just worried that something internally caused it to crack and patching it may allow it to run really lean and burn up the motor.