GT150 Problems

[piperdriver]

Re: GT150 Problems

Don't give up yet. You already checked compression. The next thing is to check the wide open rpm's. Get a tach that works, beg, borrow, steal one. This is an essential part to troubleshooting. Does the motor run smothe at the speed? If you are having to use the primer every time you start it, that indicates a lean condition. I forgot to ask, do you have a shop manuel for this?

 

[wtp]

Re: GT150 Problems

yes I do have a manuel

 

[wtp]

Re: GT150 Problems


Still having problems with my boat. I took the coils off and had them tested and they tested good. Replaced the wires because the old ones had alittle rust in them. When I had the boat out tonight I noticed some I think mixed gas seepage by where I think the crankcase seperates but I'm wondering if it aint coming out of them little covers on the side of the head. Either way I wouldn't think there should be gas in either location. The red line is where the gas is running down. It's not alot but it is noticeable. The other pic is where the coils are and seem to be somekinda oil but doesn't seem recent. Not sure if it is part of my problems but It is something I noticed. Take a look and see what you think. Any help would be great. I also looked at prop size as somebody asked. The boat is a 1986 hydra sport 17' and the prop says 391200 15x7. looks to be correct size

 

[wtp]

Re: GT150 Problems

prop size is 15x17 not 15x7. Sorry

 

[wtp]

Re: GT150 Problems

did some more testing tonight. I did have the coils tested and they tested fine. tonight I built a spark tester. now from what I read the spark should jump 7/16 inch. I set it at 1/2 inch and all do jump. Here is my concern It's not a "wide" blue spark like I read. It is more of a thin whiteish spark and it's not a constant spark. You'll get like 5 or 6 in a row and the a pause, then 3 and then a pause. numpers are not exact but you get the idea. not a constant spark. i did do the test with all plugs out. and yes the tester was plugged right into the coil. not sure if it maters but my tester plug wire is about 16 or 18 inches long and ground wire is about the same.

 

[wtp]

Re: GT150 Problems

nobody has any answers or ideas?

 

[wtp]

Re: GT150 Problems

Bump

 

[wtp]

Re: GT150 Problems

bump ----- could use some ideas

 

[wtp]

Re: GT150 Problems

I'll have to see what happens. All my parts showed up today. I got new reed valves but found out there good. See very little light on a few but according to the book you will but as long as it's no more than 0.010 on the feeler gauge. I'm well smaller than that. I did put new gaskets in though. Also replaced the big intake gasket. I also picked up a new stater cause mine was black (burnt) on the 2 thing were the wires come out. It still charged though. Picked up new power packs also and the 6 cover gaskets and will get them in today. I also picked up a new rectifier but mine looks brand new. There isn't even dirt or anything on the wires or the box. I know that doesn't mean anything. I'll try figure out how to test that later today or tomorrow. My goal is to dump it into the lake this weekend and give it a shot. I didn't see any where in my book when I put on my new power packs theres little brown wires that go to the coil. Does it matter which one goes on which coil? I would think it would due to firing order.

 

[wtp]

Re: GT150 Problems

I found a colored wiring diagram and it looks like it does matter on the power pack to coil wires.

 

[j_k_bisson]

Re: GT150 Problems

As to what wire goes to what power pack. Yes it does matter. The new power pack should have the same colour lines on the wires. Just match up the old location/color to new wire.

 

[wtp]

Re: GT150 Problems

does anybody know if there is a certain order the carbs go back on. The middle one is easy do to the throttle linkage but does it mater for carb 1 & 3? I have them soaking in carb solutuion now and would like to clean them and reinstall tonight. Also i wrote down where my yellow stater wires go with one yellow and one yellow with a gray strip but got my new stater and there is no markings just 2 solid yellow wires.

 

[j_k_bisson]

Re: GT150 Problems

The stator wires are polarity driven. (+/-) So, yes they do matter. You need to look closely at the wires and see if there is not some kind of marking system on them. Also if you do not find it then call the company, cdi probably, and ask them how to identify or if there is a polarity issue with hook up.

As to cark there should not be a difference. But som motors do have different jetting between top and bottom carbs. Did you check the main jet numbers from carb to carb? That would answer your question. The bodies are the same.

 

[wtp]

Re: GT150 Problems

dbl checked and there is no markings on the wires

 

[wtp]

Re: GT150 Problems

I called CDI Electronics and the guy told me there is no (+/-) it produces a a/c current. Yellow to Yellow. I sure hope he is right

 

[clanton]

Re: GT150 Problems

If you look at the BRP parts site for 1983 150 with 2 pumps, will show 2 pulses hose, one for each pump. One pump pumps to the other pump, which pumps to a common fuel rail/manifold.
I would use the blue tip hose connector that screws into the block for each pump. Upper and lower carb should be same. Jet size should be verified by service bulletin.

BEFORE you spend any more money, should find the fuel leak on side on engine, photo in post 24. If leak is at the block, block will have to come apart for inspection and reseal. If engine run, you should see bubbles at the fuel leak.

 

[clanton]

Re: GT150 Problems

No problem with the yellow wires, just connect them yellow to yellow.

 

[emdsapmgr]

Re: GT150 Problems

Your fuel leakage from the crankcase may be a problem. The crankcase halves do not have a normal type seal between the two halves. OMC uses a gel type sealer which you squeeze from a tube as that sealer. Normally it lasts for the life of the engine. If it breaks down, you can see fuel bubbles where the crankcase halves meet. The bubbles will be from fuel coming out. If fuel bubbles out on the compression stroke, air will surely enter on the suction stroke. Not a good situation. It will cause to running issues. You really have to split the two crankcase halve and reseal the case. The leak around the aft outer exhaust cover is probably exhaust. Not as big a deal, but if that area is leaking exhaust, you may find it is also leaking water internally. I'd pull the plugs and check for any water intrusion in the cylinders, esp the two bottom ones. The piston tops may look washed. Try retorquing the exhaust cover bolts. Your compression is probably close to normal. It is not unusual for the compression to vary perhaps 5 lbs between the two heads, due to manufacturing differences at the factory. An inductive timing light will show you the quality of spark on each cyl. Run the engine and check the spark with the timing light. It will tell you if the spark is intermittent, weak, etc.

 

[wtp]

Re: GT150 Problems

well still no go. I put in those 6 gaskets (3 on each side of block) put new power packs on, soaked carbs in berryman cleaner. Found nothing in the jets. Checked jets and they are the right ones for the carbs. rechecked fuel lines. put on a tach. had a buddy drive next to me with a 85 force we were going 35mph and tach was reading 4900 rpms. my speedo says 25mph so that don't work right either. top end is smooth but should be faster. this is the best part. choke the hell out of it and it starts to spit and sputter then you have to grab the fast idle and rev it up to clear it out. it sputters until it gets going and then smooths out. carbs seem dry but on start up it's all wet like there flooding. But have to use choke to start it. Not sure if it's getting gas running out the front of the carbs from flooding or from it sputtering which still could be flooding. I'm total lost now. Here is a summry of whats been done. New plugs, wires, fuel lines, 2 fuel pumps, power packs, stater, 6 side gaskets on the side of the block, reeds are good, replaced intake gaskets, set timing (used directions in top secret file section) cleaned carbs 4 times, jets are clear, float is level when held upside down, new needle and seat. checked pickup tube in tank. shot gas in carbs with spry bottle at wot and motor seem to bog down when I did it but that was a hard test trying to drive the boat and spray gas. also new prime bulb and checked compression which was within specs. So there it is. Whats next other than let it sink.

 

[j_k_bisson]

Re: GT150 Problems

Ok My thoughts are if it is is bogging/flooding at idle then its either your choke system (aka prime solinoid) or your recirc system. Have you checked all your recirc vavles in your intake and block. Make sure none are stuck closed, or open.

Also could be your primer valve is not closing and flue is flooding the system there. Or an air leak and with one of the hoses, Or a crack in the fuel line. Actually mine the nipple of the plastic top had a crack in it allowing a air leak. Maight want to get the rebuild kit for the primer solinoid. It's like $15 and new fuel lines.

You say your card have been done 4 times. When you rebuilt them, did you flip them over/up side down and tried to blow in to them. If the seats are new then they should not allow air to pass. If they do then you are getting flooding from that carb.

What gaskets on the block did you replace? Head gaskets?

The other thing that tickles my curiosity is when you said that the gas spray bottle trick cause the motor to bog. But your where driving the boat. If it boggerd then you are fuel rich, not running lean. So your main jets are good and so is your fuel pump. You do not have a fuel restriction at WOT then. You will deffinately want to redo this "Trick" again with help. This will tell you allot reguarding what your problem with speed is. Idle is flooding/runnig rich from what you have said.

Everyone correct me if I am wrong with reading into his discription of the problem. He is looking for help and I am try with what I know of these motors. This is all I can come up with from you observations. I hope it helps.