Loosing spark

[Andy bauska 27]

Not disagreeing, I just don't own an 88.

[Andy bauska 27]

Although there are some that are 93 only. And I just looked and my box says HC5 on it. This is the box that was only used in 93. So could this be the issue after all?

 

Edited January 22, 2022 by Andy bauska

[shadetree 5,864]

5 minutes ago, Andy bauska said:

Although there are some that are 93 only. And I just looked and my box says HC5 on it. This is the box that was only used in 93. So could this be the issue after all?

 

you cant go by those first letters on the box..you need the whole part number.

[shadetree 5,864]

8 minutes ago, Andy bauska said:

Not disagreeing, I just don't own an 88.

i've had my hands on a few 88's..i know for a fact that the c.d.i. for this year model is a one year only c.d.i. I DON'T CARE WHAT EBAY..AMAZON..OR ANY OTHER SELLER CLAIMS ?..I KNOW THIS FOR A FACT !.

[shadetree 5,864]

I just looked at the 1993 trx300fw c.d.i. on partzilla, i noticed they had two versions of c.d.i's on the list...one covers a few years ( no 1988 in there ) the other c.d.i. covers ..guess what ?..ONLY 1993 TRX300FW !.

[shadetree 5,864]

depending on what model trx300fw you have ?, will say which c.d.i. will run on yer atv. there are some trx300fw that has an A after the model, and some have AN after the model. a quick look-up of yer vin number on rocky mountain atv when looking up the correct c.d.i. will narrow it down as to what correct c.d.i. fits on your atv. and of course..finding leaking carb problems helps too..lol.

[Andy bauska 27]

The plug on my dad's box says HC4, and the plug is reversed as well, which I thought was odd.

 

 

[Andy bauska 27]

34 minutes ago, shadetree said:

depending on what model trx300fw you have ?, will say which c.d.i. will run on yer atv. there are some trx300fw that has an A after the model, and some have AN after the model. a quick look-up of yer vin number on rocky mountain atv when looking up the correct c.d.i. will narrow it down as to what correct c.d.i. fits on your atv. and of course..finding leaking carb problems helps too..lol.

I don't see a way to check my VIN on Rockymountainatv.

 

[shadetree 5,864]

15 minutes ago, Andy bauska said:

I don't see a way to check my VIN on Rockymountainatv.

 

once you have yer vin number, go to rocky mountain atv, find your year model, drop down, make, drop down, then you will see a list..out to the side is a list of numbers, these are yer vin numbers that match that model/year/make, the numbers will not all be in order ?, so you have to pick from the model list that starts out with the numbers that closely match your vin numbers. have i lost ya yet ?..lol.

[shadetree 5,864]

oh..and these vin numbers also help you make out which version trx300fw you have ?, depending on what the numbers are out to the side ?, will tell you if you have a A version ?, or a AN version ?.

[Andy bauska 27]

Rockymountainatv's vin range doesn't have an x like mine does. 478TE150XPA522693 That's my vin

 

[Fishfiles 20,145]

I was pretty busy yesterday evening hosting a party and messed a lot on this CDI interchange --------  Not that it really  makes any difference  to Andy ,  that  the part number on Partzilla showing that 88  only had a one year part number ,  I know that a 88 will  run on a 88-93 CDI , just did it a  couple of years back on the old 88 2wd I sold to my buddy Ricky , I ordered the CDI , he stuck in and it still runs  -------------- also Rick's CDIs are sold 88-93 , both my 92 and 90 are both running Rick's CDI that are listed 88-93  ---- I see a lot of times when the numbers of the interchange don't line up , but the parts will interchange , the numbers get superseded 

[Goober 1,555]

11 hours ago, Andy bauska said:

Rockymountainatv's vin range doesn't have an x like mine does. 478TE150XPA522693 That's my vin

 

93 TRX300FWA

 

[Andy bauska 27]

Ok, I got the new pulse generator yesterday, and pet it in. After waiting for the gasket material to dry, I fired it up, and nothing has changed, so what's next?

 

[Misterclean 421]

1 hour ago, Andy bauska said:

Ok, I got the new pulse generator yesterday, and pet it in. After waiting for the gasket material to dry, I fired it up, and nothing has changed, so what's next?

 

Have you trimmed some of the coil wire as I suggested?

[Andy bauska 27]

No, I have not. Pardon my ignorance, but what would this fix/change?

[Fishfiles 20,145]

35 minutes ago, Andy bauska said:

No, I have not. Pardon my ignorance, but what would this fix/change?

You say you don't have spark !! 

Cutting the end off the coil wire lead and re-attaching it will sometimes fix a no spark problem as it was a bad connection between the two  causing no  spark 

 

The kill switch will also cause a problem , either with a corroded connection or broken wire inside the switch ,  both have happened to me 

 

did you by any chance change either the flywheel or the stator , as there are two styles used on 300s and they need to be matched as a set 

 

are there any other parts that you changed receently 

[Andy bauska 27]

It idles great! I've never had a problem with it not starting/ idling. It's when I put the throttle to it, the spark comes and goes, and it misses. I have not replaced the stator or flywheel. I believe both are original, but I do not know, I've only owned it since August 2020. I also put a Brand-new OEM coil in it, and it didn't change anything.

[ATC4ever 1,078]

This is harder to diagnose not being right in front of us. Is the flywheel clean where the PG is? Any possibility there is a gap there?

[Andy bauska 27]

I was looking in the book, and there is no gap spec. It would be kinda hard to move it, because the holes are where there are.

 

 

 

[Misterclean 421]

5 hours ago, Andy bauska said:

No, I have not. Pardon my ignorance, but what would this fix/change?

The inner wire where it threads into the cap can degrade over time causing weak and erratic spark

[Misterclean 421]

You may be misdiagnosing your problem. If the carb is running very rich ( for whatever reason) it will sputter badly which will cause a timing light or spark tester to flash much slower because the engine rpm's drop suddenly. In other words it may have a very rich condition. Without me actually being there we can only give educated guesses.

[toodeep 1,758]

Just a question. Did you rule out air flow with all the switching of stuff? I've seen mice and cutter bees build nest in the intake tubes that would restrict air flow at higher rpm ranges. Possibly a long shot but also the carb vent line while your checking stuff,. The overflow should take over if it's plugged but I don't know the complete history of the machine.

[Misterclean 421]

Too Deep...I agree, I had a mud dobbers nest in an intake snorkel once. Andy, another thing to check is the spark plug cap. It has a resister built into it. Perhaps you could jump the bare coil wire straight to the spark plug. Can't remember ......are you sure the spark plug is good? I've seen them spark good outside on the head but not under compression.

[_Wilson_™ 6,566]

7 hours ago, Misterclean said:

Too Deep...I agree, I had a mud dobbers nest in an intake snorkel once.

 

i agree with you both, dobbers mice, and wasp, cause so many issues around here, we had a few bikes (atvs) come up to the shop just because of breathing issues, intakes almost completely plugged up, and had one honda300 2wd and the exhaust was completely packed with shelled corn, when we told the owner...... wow! did he get angry...... i use metal storm door screen on my equiptment intakes. 

Edited January 26, 2022 by _Wilson_™