1992 350D Starting problems

[Fishfiles 20,145]

I think I'd have a first go at a " fresh " battery that wasn't " flat " , you going'ist be needing one anyways , fuel pump or CDI might be running short of  'tricity ----- 2 1/2 turns out on the air mix 

[Goober 1,555]

I agree with you on the battery Fish as this could create weak spark.
but the initial pilot screw setting for a  TRX350D carb is 1.5 turns out; with sweet spot between 1.5 to 1 5/8 turns.

TRX300 yes between 2 to 2.5 turns is the sweet spot.

High altitude settings might apply too if Pip is in the Highlands in which a leaner mix would be desired 

[Fishfiles 20,145]

23 minutes ago, Goober said:

I agree with you on the battery Fish as this could create weak spark.
but the initial pilot screw setting for a  TRX350D carb is 1.5 turns out; with sweet spot between 1.5 to 1 5/8 turns.

TRX300 yes between 2 to 2.5 turns is the sweet spot.

High altitude settings might apply too if Pip is in the Highlands in which a leaner mix would be desired 

You might be right on the 1.5 to 1.625 turns as I know you are up on the books , I remembered you saying that before I posted  2.5 ,    I was talking with Shade last night about what he sets his 350's at , and we kind of both agreed on 2.5 as a start on everything 

[TrxPipUK 169]

Thankyou both very much! I will report back when I do it, will probably be on the weekend 

[TrxPipUK 169]

On 12/12/2020 at 11:25 PM, oh400ex said:

 

Yes the engine needs to be at top-dead-center but on the compression stroke. Make sure the mark is perfectly lined up and that the piston is at TDC.

Intake > Compression > Ignition > Exhaust 

You can have the piston at the top on the compression stroke or the exhaust stroke just make sure it's on the compression stroke.

Basically... if you saw the intake valve close just before getting TDC... you got it!

If you just saw the exhaust close it would be wrong.

 

Service manual does explain this fairly well if you would like a more precise explanation.

 

Good luck with it!

Just looking at the valves to check the clearances again seeing as I had the carb off. 

And looking at it whilst turning the engine over by hand it seems as though the compression stroke is straight after the exhaust valves shut... this doesn't seem right? I've got the spark plug in as well so I know when the compression stroke definitely is. 

Does anyone have an explanation as to why it's like this? Would the valves be set right as long as it's on the compression stroke?

Funny thing is that it runs so surely everything is fine? Lol

 

I'll get a video 

 

[oh400ex 629]

50 minutes ago, TrxPipUK said:

Just looking at the valves to check the clearances again seeing as I had the carb off. 

And looking at it whilst turning the engine over by hand it seems as though the compression stroke is straight after the exhaust valves shut... this doesn't seem right? I've got the spark plug in as well so I know when the compression stroke definitely is. 

Does anyone have an explanation as to why it's like this? Would the valves be set right as long as it's on the compression stroke?

Funny thing is that it runs so surely everything is fine? Lol

 

Generally confused a bit but think you may have it timed at "180 out"

Honestly... it may not even matter. I never personally do anything but time on the compression stroke... 

This article may help clarify a few things... took a few of the highpoints but feel free to give it a closer look

Edit: Confused after watching the video... not sure what I'm missing but something...

 

Quote

Am I 180 out?

 

People ask this a lot when they have trouble getting an engine running after they’ve set the cam timing up, or when they bring the piston up to Top Dead Center and find both valves open.  This is the common mistake we mentioned earlier, and it's one of the things that's more easily understood when you have a good grasp of the complete cycle.  It’s more of a car thing, but if you have an old classic four-stroke from the ‘70’s or before that uses cam driven breaker points, it’s sometimes possible.  These days, the answer is usually, “no.”  The old way of connecting the ignition to the engine mechanically, that of using a distributor or some other device driven at half speed by the cam, allows a mistake in assembly to be made.  A mechanic could position the engine at TDC, and if not careful to check, he could position the ignition trigger to fire during the exhaust stroke instead of the compression stroke.  This was referred to as being “180 degrees out” because the distributor or point plate was 180 degrees away from the correct position on the camshaft because of this. Actually, going by the crank, the ignition timing was 360 degrees out.

But with the ignition trigger located on the crankshaft instead, as is the case with virtually all modern single cylinder dirt bike 4 strokes, that’s not possible.  Without the cams connected to the crank, one TDC is exactly like another; the rod’s at the top, and the spark signal is given as the crank gets there, every time.  So, the only thing that determines which stroke is which is the camshaft(s), and how they are positioned by the assembler.  That’s why the service manuals for such engines make no mention of checking for which of the two different TDC’s is used.  In operation, there is a second, "wasted" spark that happens near the end of the exhaust stroke. 

 

 

Edited December 18, 2020 by oh400ex
Gif

[TrxPipUK 169]

23 minutes ago, oh400ex said:

 

Generally confused a bit but think you may have it timed at "180 out"

Honestly... it may not even matter. I never personally do anything but time on the compression stroke... 

This article may help clarify a few things... took a few of the highpoints but feel free to give it a closer look

Edit: Confused after watching the video... not sure what I'm missing but something...

 

 

 

Yes I am confused about it as well...

 

Reading that article and surely if it was 180 out then it wouldn't run? Will it be okay running like this or will I have to go back into the engine and and sort it out properly? 

I can't see how it would be like this though.

I remember when setting the timing I thought it looked all backwards when turning it over, but I had the timing spot on so I went with it.

 

Can I just run it like is? 

[oh400ex 629]

6 minutes ago, TrxPipUK said:

Yes I am confused about it as well...

 

Reading that article and surely if it was 180 out then it wouldn't run? Will it be okay running like this or will I have to go back into the engine and and sort it out properly? 

I can't see how it would be like this though.

I remember when setting the timing I thought it looked all backwards when turning it over, but I had the timing spot on so I went with it.

 

Can I just run it like is? 

 

Are you possibly turning the motor backwards?

Does it turn the same direction when moving the motor with the kicker instead of the ratchet?

Dunno if that would produce what you are seeing...

 

Edit: If there was a serious problem it would not run. It is either not susceptible to the "180 out" or timed correctly.

Edited December 18, 2020 by oh400ex

[TrxPipUK 169]

15 minutes ago, oh400ex said:

 

Are you possibly turning the motor backwards?

Does it turn the same direction when moving the motor with the kicker instead of the ratchet?

Dunno if that would produce what you are seeing...

 

Edit: If there was a serious problem it would not run. It is either not susceptible to the "180 out" or timed correctly.

That is a good point! I'll check which direction it turns with the kicker. However, I am turning it clockwise as the manual says to.

 

As long as it's not going to be damaging the engine in some way then I'm happy to just run it as is.

Thanks 

[Goober 1,555]

Sounds incorrect @TrxPipUK

Set the valves on the compression stroke—after intake valve Open/closure —you’re looking for the timing mark just after—And before exhaust valve movement.

 

your exhaust valves will be too loose otherwise 

you’re not 180 out but on the exhaust stroke the exhaust valves are on their way to being but may not yet be fully seated. This makes complete sense to me because you complained the exhaust valves were too tight. Now I’m sure they are too loose.

Edited December 18, 2020 by Goober

[Fishfiles 20,145]

I know from reading about the 350 head on a  300 engine build ,  when running , a 350 turns the opposite way of  a 300 ,  just saying ! 

[Goober 1,555]

Manual advises clockwise rotation page 3-5 under Valve Clearance

[TrxPipUK 169]

2 hours ago, Goober said:

Sounds incorrect @TrxPipUK

Set the valves on the compression stroke—after intake valve Open/closure —you’re looking for the timing mark just after—And before exhaust valve movement.

 

your exhaust valves will be too loose otherwise 

you’re not 180 out but on the exhaust stroke the exhaust valves are on their way to being but may not yet be fully seated. This makes complete sense to me because you complained the exhaust valves were too tight. Now I’m sure they are too loose.

I think I'm just struggling to find TDC on the compression stroke.. At one of the TDC's the intake valves begin to shut but before they do the exhaust valves are beginning to open. It's like they're both just off their seats. This doesn't seem like the compression stroke as there is no resistance when turning the engine and there is no clearance between valve stems and the rocker.

At the other TDC there is compression when the piston is coming up and once the valves seat then there is a lot more movement of the piston before any valves open again, there is also clearance between the valve stem and rocker. So this seemed to be the compression stroke to me apart from that the last valves to close were the exhaust and not the intake, maybe it would make more sense to turn the flywheel round anti clockwise and see if it's easier to find the compression stroke that way.

 

Am I right to be turning it clockwise? When I used the kickstart the flywheel turned round in a anti clockwise direction. Surely it would be better to turn it over by hand that way as well even though the manual says turn it clockwise? 

 

I hope my little ramble there makes a bit of sense.. I don't know why I'm finding it so hard to get the piston and valves in the correct position lol

[Goober 1,555]

Manual says clockwise—if you’re rotating anticlockwise the valve pattern will be different so maybe that’s the cause of cornfusion.

use a socket with extension on a breaker handle—using a ratchet allows the piston to fall away from TDC.

Also remove the spark plug so you’re not rotating it under compression much harder to get on the T

Edited December 19, 2020 by Goober

[oh400ex 629]

1 hour ago, Goober said:

Remove the spark plug so you’re not rotating it under compression much harder to get on the T

2nd this... have to get lucky with the plug still in

 

1 hour ago, TrxPipUK said:

Am I right to be turning it clockwise?

 

Not from the sound of it... 

 

1 hour ago, TrxPipUK said:

When I used the kickstart the flywheel turned round in a anti clockwise direction. Surely it would be better to turn it over by hand that way as well even though the manual says turn it clockwise? 

 

Whatever rotation the kicker moves the flywheel in is the rotation you should be using. 

Turning it backwards with the ratchet explains the confusion.
 

I'd put it on the proper stroke with mark lined up and readjust the valves.

 

Edit: I'm getting a bit suspicious of your manual... are you using a Clymer or something lol

Here is an excerpt from my 350x manual (same top end as 350D)

 

Notice how this is saying counterclockwise rotation on the flywheel

 

 

Edit 2:

Factory (86-89) service manual says clockwise. (92 running different bottom end?)

Still not sure what's going on but here is the long/short...

 

Anti-clockwise is the way that motor turns when running... right? Spin it anti-clockwise

Once the valves are re-adjusted on the compression stroke... run it!

 

Someone (shade) is going to step in here, see "the blind leading the blind" and shine some light on this situation shortly. 

 

Edited December 19, 2020 by oh400ex

[_Wilson_™ 6,567]

https://atvhonda.com/topic/166-1992-350d-starting-problems/page/22/

 

pip ^^^^ kind of sounds like you were right on timing. 

[Goober 1,555]

Yup @TrxPipUK You’ve done alright. 
 

Let me emphasize that the manual says turn engine clockwise using the flywheel bolt head. clockwise. Clockwise.
 

Pull the spark plug.

 

use a deepwell socket and a breaker handle because these have no ratchet—easier to control the rotation and resist tendency of the piston to pull the flywheel around on its way to the bottom of the power stroke.

Rotate the engine clockwise a few times to watch the valves open and close. When you see the exhaust valves close be ready for the intake valves to open. On their way closed, watch that flywheel for your mark. 
you can make small adjustments CCW and CW.

 

 

Edited December 19, 2020 by Goober

[Goober 1,555]

@oh400ex i don’t know which direction the kicker moves the engine—just remember direction is based upon perspective. If you’re following the manual you’re turning the engine CW; if you’re not following the manual (standing on the right side with the kicker) the engine is turning CCW

Edited December 19, 2020 by Goober

[_Wilson_™ 6,567]

sounds to me like if you turn it clock wise via the fly wheel (which is correct) the kick starter would to. simple test,  while your turning the fly as goober said (by the fly wheel clock wise) see if the decomp works, if so, then you have your answer, the kick starter turns the engine clockwise, but according to page 22 your timing is right. 

[oh400ex 629]

3 hours ago, Goober said:

@oh400ex i don’t know which direction the kicker moves the engine—just remember direction is based upon perspective. If you’re following the manual you’re turning the engine CW; if you’re not following the manual (standing on the right side with the kicker) the engine is turning CCW

 

The point I was trying to make is that it doesn't actually matter what the manual says. Is it the correct manual year? UK?

If the motor is turning a specific direction-of-rotation while running... that is the direction-of-rotation used when coming up to TDC.

 

If you didn't have the manual you would always want to turn the engine the way it turns while running... right?

Otherwise you would be running the 4-stroke process backwards which is what I believe we are seeing in the video above.

Explains why he saw the compression after the exhaust valves closed, why the bike runs correctly and why the photos he posted of the timing marks and cam look correct (they are)

 

Like I said above my guess is that the 92 350 available in the UK has different bottom end than what is showing in the manual I have access to.

Don't actually have the service manual for the 92 personally but my 350x is counterclockwise with the same top-end components so logical explanation from my perspective

 

He is probably snoozing at the moment but will likely only need to turn the engine whatever way it does while running (or turning with the kicker) and set the valves on the compression stroke to be fully fixed up.

Edit: Misunderstanding (like you said above) is also very possible... clockwise on one side of motor is anti-clockwise on the other

Edited December 19, 2020 by oh400ex

[_Wilson_™ 6,567]

 

pip if you did like this cam lobes down, timing gear marks level with the head, and a t showing in the second port hole, your timing is correct, this engine rotates clockwise from the left hand side, counter clock wise from standing on the right hand side. standard rule is the engine is clockwise if the fly wheel turns clockwise. which means the kick starter turns it the same. and from the video, you turned it the right direction, because the timing chain was turning backwards (seen via intake side valve adjustment in the video) so your good to go!!

 

Edit: as goober said ----just remember direction is based upon perspective.

Edited December 19, 2020 by _Wilson_™

[retro 4,048]

Quite a discussion goin' on here eh. The TRX350 motors must be spun counterclockwise when turning the crank on the flywheel-side, same direction as the kick starter spins the crank. When ya spin the crank backwards you can feel your mistake. The crank turns hard cause the chain slack balls up in the front guide and applys lot of extra force against the dog-leg shaped rear guide.... you are putting a lot of stress on the rear chain guide and forcing the timing chain adjuster plunger back which can make them slip & the chain might jump a tooth or two.... don't ever turn a cam-chain equipped motor backwards intentionally. There is no such thing as timing the cam on a single cylinder 4-stroke motor 180 degrees out because the ignition fires BTDC on every revolution. You adjusted the valves correctly PIP!

[TrxPipUK 169]

1 hour ago, retro said:

Quite a discussion goin' on here eh. The TRX350 motors must be spun counterclockwise when turning the crank on the flywheel-side, same direction as the kick starter spins the crank. When ya spin the crank backwards you can feel your mistake. The crank turns hard cause the chain slack balls up in the front guide and applys lot of extra force against the dog-leg shaped rear guide.... you are putting a lot of stress on the rear chain guide and forcing the timing chain adjuster plunger back which can make them slip & the chain might jump a tooth or two.... don't ever turn a cam-chain equipped motor backwards intentionally. There is no such thing as timing the cam on a single cylinder 4-stroke motor 180 degrees out because the ignition fires BTDC on every revolution. You adjusted the valves correctly PIP!

Thankyou everyone and thankyou @retro for stepping in and giving an explanation, much appreciated. 

 

Makes a lot of sense that the engine turns over counterclockwise as that is the way the kickstart turns it over (I have checked multiple times now lol). My biggest question is why does the manual say to turn it clockwise when that is definitely NOT the correct direction.. very confusing. Thanks again for clearing that up retro, I'll turn the engine over counterclockwise and check all is okay. 

 

Thankyou everyone 

[oh400ex 629]

2 hours ago, TrxPipUK said:

Thankyou everyone and thankyou @retro for stepping in and giving an explanation, much appreciated. 

 

Makes a lot of sense that the engine turns over counterclockwise as that is the way the kickstart turns it over (I have checked multiple times now lol). My biggest question is why does the manual say to turn it clockwise when that is definitely NOT the correct direction.. very confusing. Thanks again for clearing that up retro, I'll turn the engine over counterclockwise and check all is okay. 

 

Thank you everyone 

 

Welcome!

Takes doing it wrong before to recognize things like this. Doing it wrong a bunch of times before getting it figured out is kinda my thing 😁

 

You are now the forum's expert on what the symptoms of turning the engine backwards while attempting to find TDC look and sound like lol

 

Like you, I am curious why the manual I have access to (86-89 Foreman 350) says clearly to turn the flywheel clockwise (incorrect)

Wondering if it is actually CCW for every 350 or if the 92 UK model you have is different.

 

Either way you got it figured out

Nice work!

 

Thank you for sharing!

 

[Goober 1,555]

The manual says to turn the flywheel in clockwise direction; hard for me to believe this is the first anyone has heard of this editing error.
 @TrxPipUK can you tell us if this is a counter-rotating flywheel? Pop the flywheel cover and pull starter gears. Does the flywheel turn opposite of bottom end?