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Originally posted by: BigBully
I have an 87' 350TRX that I bought in 89. I've beat the heck out of it and gotten my use out of it. I recently rebuilt the whole engine. Before that it has been a really reliable machine. It does ride a little like a tank. There is definately a problem with the fuel pumps. I replaced it with an aftermarket pump. (You have to find a hot wire from the fuse box since the wire for the OEM fuel pump is a pulse).
I think it should be worth about $2000.
dose your 350 with fuel pump problem shut off the engine when you shift it in foward
or reverse My 86 350TRX when the engine is cold it starts up ok can rev it up in nuteral ok
but shift it into foward or reverse its just like shuting the key off ? put it in nuteral and starts
right back up and revs up just fine. After the enging warms up to normal operating temp
i can shift it into foward or reverse just like normal it runs good warmed up.
This has me puzzeled i'm thinking oil/temp sensor or nuteral or reverse switch i'm pretty
sure it's electrical
Eddie42, At first, you would think it is a problem with the carburator or fuel. Acutally the battery is probably dying or needs replaced. When you get it warmed up and the battery is charged up then it is generating enough power to keep the fuel pump running. Similar problem when it runs fine until you slow down around a corner or something then it shuts off.
The battery is fairly new and has pleanty of starting power when it is cold or warmed up
If it was the fuel pump wouldn't it not start at all.It starts and runs good in nuteral when
cold but try to shift into foward or reverse it shuts right off as if turning off the key or
shutihg the kill switch to off.
Take off the seat. Look along the frame rail where the seat rests, just above the side covers. There are some wires routed there that the connectors have been known to get loose. Since they are single bullet connectors with black rubber coating, the female ends can be slightly snugged with a plier and reconnected. I have had heavier riders of those old 350's that after prolonged use they sag the seat and will actually stress these connectors, from the seat pushing against them just enough to loose connection when shifted into gear killing the engine. It is worth looking into.
I have also been seeing CDI problems lately on the old thugs doing the same thing
Carb problems with them around here are generally taken care of by replacing the needle jet set. If the unit pushes any black smoke from the exhaust, the jet needle has rattled a groove in it and worn the needle jet. Also on the side of the carb under a plastic cover there is a link assembly from the throttle cable plate pivot to the venturi. If the gap in the fork is set wrong, it will make the venturi lift the jet needle too soon or too far as per opening position of the throttle plate, causing them to run rich and foul spark plugs after a few rides also.
Fuel pumps on these units, as noted before, will fail. To make sure the problem is cured when replacing it with a new Honda pump unit, also replace the fuel pump relay. When one of the two units fail, the other is soon to fail there after. If a relay is not replaced along with the pump, it can cause a new pump to fail shortly after install. After replaceing over 200 of the pumps and relays together I have had future failures of them on the repaired units at nearly 1 percent.
Yes, from the get go, these units have had poor starting systems. Starting with the gear tooth problem outlined by dzzy. I have also seen high amounts of one-way bearings (sprag) failures. Mainly in units that oil changes are far and in between. The starter motors on them have a 4 brush holder in them and turn over backwards compared to the newer Honda ATV starters which have 2 brush holders within. Try not to crank these units over for long periods of time. Premature brush wear will result. Note: the brushes on these starters will wear down to the wire leading to the brush and will destroy the armeture when the brush wears out. Newer Honda starters (2 brush type) have a stopper, so to speak, within the brush holder plate thet will keep this from happening. As I stated before, the newer (better designed) starters will not interchange into the older 350's, as they turn the wrong direction.
Lumber wagon ride on the pre 90's 350's are result from short travel suspention, and also contributing is the fact they do not have front A-arms. Rather a front swing arm simular to the rear on a solid axle quad. If looking into purchasing one of these quads, pay some attention of the pivot bearing condition of the front swing assembly. It is a neglected part in maintainance by owners and many "oil change" type bike shops (non dealers).
Hope you can utilize some of this info... In good condition they are a pretty good work horse, not a speedster though
----- Gimp -----
Not all winners are heros
Honda Pro Wrench - Red Level Certification
I had a similar probem, it would start cold, but then just die. It was never predictable in the begining, but then it started cutting out about a minute after I started it every time, it was definately electrical. I can't remember exactly what lead me to do this, but I was playing with the wires on the right hand side of the seat. Somehow I grounded the light green wire with the red stripe to the frame and it started! It has been running now for four years without cutting out. The connecter has the label 136F on mine if that helps, some of the connectors are labled, others are not. But look for the light green wire with the red stripe and trying making a connector for it with a pigtail and grounding it to the frame. I grounded the top half where it comes down from the seat.
The only bad side affect is that the neutral light always stays on now. I actually replaced both the neutral and reverse sensors at one point, but it still would cut out when not grounded. I don't have a wiring diagram, but I suppose the wire I grounded is for the neutral switch.