[Epoweredrc]

Hi everyone, new member did a google for 4 wheeler wont run and found this site maybe someone can help me, My father has a 1988 Honda 300 trx 2wd Four wheeler, its been in family about 11 years its always crank and ran great. had some issues with the shut off on the peacock and dad JB welded that shut few years ago and it ran good after that we stuck another shut off inline before the carb after he did that. its battery been dead for years we would jump it off with a jump start box or after the first crank of the day it would kick start. Anyhow about 2 years ago after my father had a stroke and no longer able to use it i moved back home to help out and i got it out one day Rode it around the yard and property (5 acres here0 and it did great. well next day went to use it and refused to crank it would crank up but immediately die.. Well it sat a while cause didn't have any time or money to spend with it. well back in December i deiced to try and work on it got a CDI box, still wont run, I just today put a brand new Carb , air cleaner, and spark plug NKG in it and guess what same thing

I am really at a loss a buddy sugeested i try to just use good gas in a bottle and bypass the tank so we did i got a hook up for gas in a bottle held it right over the carb so it would get good suction and same thing. it crank for about 1-2 secs then dies right out.

Another buddy said check the gap pn plug well I did and read online it should be .8 or .9 well mine brand new was about .15 so i fixed it to about .9 and still same thing none of this seemed to change how it will hit then die right away

Im new here can i post a utube video link if so i can post the video i did today on what it sounds like.

i really need this four wheeler to run its got a hitch on it and i pull a small trailer with it ive got about 60 foot of trees cut down and cut up Ive got to get moved and my truck cant get down in the woods to where there at.. at this point im ready to just sell it for $300-300 if i can even get that and just find something else. Another buddy says hes the 4 wheeler king and can fix it but he always busy and wants to charge a lot.

Is there anything else i could try? i tested the coil when i replaced the CDI box and it checked good. it gets spark it doesn't seem to be a lot of spark but its there you can see it.. I also checked the 2 fuses where the battery goes and there both fine.

Another buddy said it could have low compression it wont run if it does have low? what would make it have low compression?

Thank you all for reading this.

 

[fishfiles]

maybe the fuel tank was contaminated with bad fuel and when you tried it , hooked to the tank , before you tried an external fuel source , you recontaminated the carb -------- maybe you bought a after market carb off e-bay or such and it is not worth the powder to blow it to hell ------- a compression test would be the place to start , in a perfect world 185-205 psi , 150 and it will still run ok , 100 and it is about dead -------- you have to have a good spark , and the timing chain has to be tight , if it is loose then the timing will be off

 

[Goober]

I would rebuild the OEM carb for one–your quad will run better with it than a non-OEM carb.

I suspect your stator may be cooked due to running it with a dead battery.

Link to users manual in my sign block –check out the ignition diagnostic charts

Well I see my sig block is now missing

 

[Goober]

Here’s another thing did you buy a knockoff CDI too? There are at least three different year group CDI

 

[Epoweredrc]

maybe the fuel tank was contaminated with bad fuel and when you tried it , hooked to the tank , before you tried an external fuel source , you recontaminated the carb -------- maybe you bought a after market carb off e-bay or such and it is not worth the powder to blow it to hell ------- a compression test would be the place to start , in a perfect world 185-205 psi , 150 and it will still run ok , 100 and it is about dead -------- you have to have a good spark , and the timing chain has to be tight , if it is loose then the timing will be off

well i had a inline fuel filter. so i feel like the carb is fine.
How do you check the timing chain? i almost feel like the timing some how got off.
i guess i will borrow the compression tester.

 

[JohnnySolo]

Fish and Goober said it well. Do those things, also let us know what color spark you have. And yeah you can paste the link to your video and we can watch, that's how we tend to post vids on here. The main thing that can happen when you have low compression is warn rings. You can tell alot of you engine by running a compression test so ask a buddy for a compression gauge or buy one for like 20 bucks. Run the test and get back with us.

Btw as these guys asked, did you get OEM carb? If not then there is your culprit

 

[Epoweredrc]

I would rebuild the OEM carb for one—your quad will run better with it than a non-OEM carb.

I suspect your stator may be cooked due to running it with a dead battery.

Link to users manual in my sign block —check out the ignition diagnostic charts

Well I see my sig block is now missing

Well we used it for years with the battery being bad. my dad put a smaller battery in it it worked for a bit but the last few yrs we have just jumped it off. Never knew that could hurt anything.

I got the carb off Amazon also it looks just like the factory one. Ive heard many people saying they get them off there. Its doing the same thing with old carb or new one. So not sure that makes sense.

Here’s another thing did you buy a knockoff CDI too? There are at least three different year group CDI

Not sure, I got it off amazon.

Fish and Goober said it well. Do those things, also let us know what color spark you have. And yeah you can paste the link to your video and we can watch, that's how we tend to post vids on here. The main thing that can happen when you have low compression is warn rings. You can tell alot of you engine by running a compression test so ask a buddy for a compression gauge or buy one for like 20 bucks. Run the test and get back with us.

Btw as these guys asked, did you get OEM carb? If not then there is your culprit

This is the CDI Box i purchased
https://www.amazon.com/gp/product/B01N3AWD7N/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

this is the carb
https://www.amazon.com/gp/product/B010TQOAXW/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

here is the video you can hear what it does.

Not sure how i missed the other 2 comments before.

Is there a way to test the Voltage Regulator Rectifier would it have anything to do with it?

 

[shadetree]

that is a china carb !!!!.

 

[shadetree]

and i'll bet all the money in the world if you want to bet ?!..lol. oem trx300 carbs....DO NOT HAVE A PLASTIC FUEL INLET !!!, THEY HAVE A PRESSED IN BRASS FUEL INLET .

 

[shadetree]

first, do a compression test, anything under 100 psi ?, time for a top end rebuild. if compression is low ?, put some engine oil in through the spark plug hole, crank it over with throttle held wide open ( always do this when checking compression ). compression will go up, reason: rings can work loose from the piston, herby increasing your compression, this is a sign of worn or stuck rings. check your timing, service manual explains how to do this, you can down load it for free from our site here. next, with spark plug in the boot, lay it on the engine, crank it over, nice blue spark, or at least a spark ?, then that's good. if not ?, then c.d.i. is bad ?, reg/rec is bad ?, you may have ruined your stator by riding it with no battery....NEVER RIDE THEM WITHOUT A GOOD BATTERY IN THEM, or you will burn the stator out, or reg/rec !.

 

[Epoweredrc]

that is a china carb !!!!.

Okay.

and i'll bet all the money in the world if you want to bet ?!..lol. oem trx300 carbs....DO NOT HAVE A PLASTIC FUEL INLET !!!, THEY HAVE A PRESSED IN BRASS FUEL INLET .

Yeah that was only thing really looked driffrent.

first, do a compression test, anything under 100 psi ?, time for a top end rebuild. if compression is low ?, put some engine oil in through the spark plug hole, crank it over with throttle held wide open ( always do this when checking compression ). compression will go up, reason: rings can work loose from the piston, herby increasing your compression, this is a sign of worn or stuck rings. check your timing, service manual explains how to do this, you can down load it for free from our site here. next, with spark plug in the boot, lay it on the engine, crank it over, nice blue spark, or at least a spark ?, then that's good. if not ?, then c.d.i. is bad ?, reg/rec is bad ?, you may have ruined your stator by riding it with no battery....NEVER RIDE THEM WITHOUT A GOOD BATTERY IN THEM, or you will burn the stator out, or reg/rec !.

Alright then, i will get the tester and test if it is low then guess i will just sell for anything can get im not in mood for rebuilding I can find these things all day under $2000 rather buy a newer model then put lot money into this. it ran great for 5 yrs think we got our $800 out of it.

 

[JohnnySolo]

Lol sorry to tell you that's a china carb and buying an OEM one is going to be over hundred bucks for sure lol. Shows you pay for what u get. Check those things shade has you doing, I'm sure we'll get that sucker going!

 

[Goober]

@Epoweredrc
Yup it makes sense to me that the new carb didn’t solve the problem.

It is an ignition problem I’ve had similar issues before. You spray some gas in the carb and it sputters then quits. That’s typical of ignition malfunctions. There is a good explanation here somewhere I’m sure @shadetree and @retro and others stated elsewhere in more detail. Ignition power circuits rely upon the pickup or exciter coils, battery, stator (alternator), rectifier, etc at different phases of ignition. It varies with model and year although yours is relatively simple.

Anyway, I had same as you and replaced the OEM CDI with same. That fixed it. You replaced with a knockoff not saying it’s not working but certainly I would question its reliability and compatibility. There’s not a good way to bench check CDI that I know.

Ok you say you have weak spark that’s important and good work.

next step for you as I see it is to check the stator leads for continuity and resistance this will tell you if the stator is cooked.

Then I would check the exciter coil (not same as ignition coil) for continuity and resistance.

—-Oh yeah borrow or buy a good battery—-

Gonna have to use the manual for that. Try the �� link in my sig block. Don’t give up yet–rock on with it!

 

[Epoweredrc]

it has low compression 120 but barely got there. my buddy messed with it for about a hour set the values and it still doing same thing he says top end needs to be rebuilt.
its a 30 yr old 4 wheeler going try get my mom let me sell it for anything i can get. and find something else i guess
I really want a 4x4 one

 

[fishfiles]

when you done the compression test , did you hold the throttle wide open , it will come up in compression when you do hold the throttle open -----120 is about dead

there are several reason why it might have low compression, the rings/piston/bore would be the most common , the timing chain having a lot of slack will also lower the compression as the timing will be off and the valves will open and close too soon or too late , a bent connecting rod will lower compression , bad valve seats , bad head gasket , out of adjustment valves , worn down cam or a combination of several

if you really want a 4x4 , you could keep that one and find a first gen 300 ( say 88-92 ) and a bunch of parts from that 88 would fit it

 

[Epoweredrc]

when you done the compression test , did you hold the throttle wide open , it will come up in compression when you do hold the throttle open -----120 is about dead

there are several reason why it might have low compression, the rings/piston/bore would be the most common , the timing chain having a lot of slack will also lower the compression as the timing will be off and the valves will open and close too soon or too late , a bent connecting rod will lower compression , bad valve seats , bad head gasket , out of adjustment valves , worn down cam or a combination of several

if you really want a 4x4 , you could keep that one and find a first gen 300 ( say 88-92 ) and a bunch of parts from that 88 would fit it

yes held throttle wide open my buddy races 4 wheelers and has build about 10 custom ones, he knows all about them
he said top end rebuild and new timing chain be best about $300 in parts and getting it bore out. but you have $300 in a old 4 wheeler. I would like something newer. if i had the money i would just go out and buy what i want but trying deal with parents cause its my dads wheeler and mom doesn't want to make any decisions

 

[fishfiles]

I hear you , it would be a waste to put money into something you really don't want to start with ------ and to tell the truth , there is a very good chance once you tear into that 88 , it might snowball into a total rebuild and you would have more into it than you could get for it , if the connecting rod is worn out and you were to rebuild the upper , you are only going to get 40-50 hours on the new upper and you will right back were you are now -----

But then on the other hand , it was your Dad's bike , which could be sentimental ,it could be a good learning experience and when you do get a 4x4 then your girl friend or friend could ride that one , as it is not as much fun riding by yourself

 

[Epoweredrc]

I hear you , it would be a waste to put money into something you really don't want to start with ------ and to tell the truth , there is a very good chance once you tear into that 88 , it might snowball into a total rebuild and you would have more into it than you could get for it , if the connecting rod is worn out and you were to rebuild the upper , you are only going to get 40-50 hours on the new upper and you will right back were you are now -----

But then on the other hand , it was your Dad's bike , which could be sentimental ,it could be a good learning experience and when you do get a 4x4 then your girl friend or friend could ride that one , as it is not as much fun riding by yourself

its just used on the property they have 5 acres, and we used it to move fallen trees, move mulch and fertilizer around and such, i originally got it 11 yrs ago and my dad wanted something for his land so i sold it to him for what i paid for it $800. my wife can't ride 4 wheelers due to back surgery she had.


thanks everyone for the input.